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Proposed Rule2023-15857

Energy Conservation Program: Test Procedures for Air-Cooled, Evaporatively-Cooled, and Water-Cooled Commercial Package Air Conditioners and Heat Pumps

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Published

August 17, 2023

Issuing agencies

Energy Department

Abstract

The U.S. Department of Energy (DOE) proposes to amend the Federal test procedures for air-cooled commercial package air conditioners and heat pumps with a rated cooling capacity greater than or equal to 65,000 Btu/h, evaporatively-cooled commercial package air conditioners, and water-cooled commercial package air conditioners to incorporate by reference the latest versions of the applicable industry test standards. Specifically, DOE proposes: to amend the current test procedure for this equipment for measuring the current cooling and heating metrics--integrated energy efficiency ratio (IEER) and coefficient of performance (COP), respectively; and to establish a new test procedure for this equipment that would adopt two new metrics-- integrated ventilation, economizer, and cooling (IVEC) and integrated ventilation and heating efficiency (IVHE). Testing to the IVEC and IVHE metrics would not be required until such time as compliance is required with any amended energy conservation standard based on the new metrics. Additionally, DOE proposes to amend certain provisions of DOE's regulations related to representations and enforcement for the subject equipment. DOE welcomes written comments from the public on any subject within the scope of this document (including topics not raised in this proposal), as well as the submission of data and other relevant information.

Full Text

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[Federal Register Volume 88, Number 158 (Thursday, August 17, 2023)]
[Proposed Rules]
[Pages 56392-56458]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2023-15857]

[[Page 56391]]

Vol. 88

Thursday,

No. 158

August 17, 2023

Part III

Department of Energy

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10 CFR Parts 429 and 431

Energy Conservation Program: Test Procedures for Air-Cooled,
Evaporatively-Cooled, and Water-Cooled Commercial Package Air
Conditioners and Heat Pumps; Proposed Rule

Federal Register / Vol. 88 , No. 158 / Thursday, August 17, 2023 /
Proposed Rules

[[Page 56392]]

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DEPARTMENT OF ENERGY

10 CFR Parts 429 and 431

[EERE-2023-BT-TP-0014]
RIN 1904-AD93

Energy Conservation Program: Test Procedures for Air-Cooled,
Evaporatively-Cooled, and Water-Cooled Commercial Package Air
Conditioners and Heat Pumps

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.

ACTION: Notice of proposed rulemaking and request for comment.

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SUMMARY: The U.S. Department of Energy (DOE) proposes to amend the
Federal test procedures for air-cooled commercial package air
conditioners and heat pumps with a rated cooling capacity greater than
or equal to 65,000 Btu/h, evaporatively-cooled commercial package air
conditioners, and water-cooled commercial package air conditioners to
incorporate by reference the latest versions of the applicable industry
test standards. Specifically, DOE proposes: to amend the current test
procedure for this equipment for measuring the current cooling and
heating metrics--integrated energy efficiency ratio (IEER) and
coefficient of performance (COP), respectively; and to establish a new
test procedure for this equipment that would adopt two new metrics--
integrated ventilation, economizer, and cooling (IVEC) and integrated
ventilation and heating efficiency (IVHE). Testing to the IVEC and IVHE
metrics would not be required until such time as compliance is required
with any amended energy conservation standard based on the new metrics.
Additionally, DOE proposes to amend certain provisions of DOE's
regulations related to representations and enforcement for the subject
equipment. DOE welcomes written comments from the public on any subject
within the scope of this document (including topics not raised in this
proposal), as well as the submission of data and other relevant
information.

DATES:
Comments: DOE will accept comments, data, and information regarding
this notice of proposed rulemaking (NOPR) no later than October 16,
2023. See section V, ``Public Participation,'' for further details.
Meeting: DOE will hold a public meeting via webinar on Thursday,
September 7, 2023, from 1:00 p.m. to 4:00 p.m. See section V, ``Public
Participation,'' for webinar registration information, participant
instructions, and information about the capabilities available to
webinar participants.

ADDRESSES: Interested persons are encouraged to submit comments using
the Federal eRulemaking Portal at <a href="http://www.regulations.gov">www.regulations.gov</a> under docket
number EERE-2023-BT-TP-0014. Follow the instructions for submitting
comments. Alternatively, interested persons may submit comments,
identified by docket number EERE-2023-BT-TP-0014 and/or RIN 1904-AD93,
by any of the following methods:
Email: <a href="/cdn-cgi/l/email-protection#02415743414a52303230315652323233364267672c666d672c656d74">[email&#160;protected]</a>. Include the docket number EERE-
2023-BT-TP-0014 and/or RIN 1904-AD93 in the subject line of the
message.
Postal Mail: Appliance and Equipment Standards Program, U.S.
Department of Energy, Building Technologies Office, Mailstop EE-5B,
1000 Independence Avenue SW, Washington, DC 20585-0121. If possible,
please submit all items on a compact disc (CD), in which case it is not
necessary to include printed copies.
Hand Delivery/Courier: Appliance and Equipment Standards Program,
U.S. Department of Energy, Building Technologies Office, 950 L'Enfant
Plaza SW, 6th Floor, Washington, DC 20024. Telephone: (202) 287-1445.
If possible, please submit all items on a CD, in which case it is not
necessary to include printed copies.
No telefacsimiles (faxes) will be accepted. For detailed
instructions on submitting comments and additional information on this
process, see section V of this document (Public Participation).
Docket: The docket for this activity, which includes Federal
Register notices, public meeting webinar attendee lists and transcripts
(if a public meeting is held), comments, and other supporting
documents/materials, is available for review at <a href="http://www.regulations.gov">www.regulations.gov</a>.
All documents in the docket are listed in the <a href="http://www.regulations.gov">www.regulations.gov</a>
index. However, not all documents listed in the index may be publicly
available, such as information that is exempt from public disclosure.
The docket web page can be found at <a href="http://www.regulations.gov/docket/EERE-2023-BT-TP-0014">www.regulations.gov/docket/EERE-2023-BT-TP-0014</a>. The docket web page contains instructions on how
to access all documents, including public comments, in the docket. See
section V (Public Participation) for information on how to submit
comments through <a href="http://www.regulations.gov">www.regulations.gov</a>.

FOR FURTHER INFORMATION CONTACT: Mr. Lucas Adin, U.S. Department of
Energy, Office of Energy Efficiency and Renewable Energy, Building
Technologies Office, EE-5B, 1000 Independence Avenue SW, Washington, DC
20585-0121. Telephone: (202) 287-5904. Email:
<a href="/cdn-cgi/l/email-protection#1a5b6a6a76737b74797f496e7b747e7b687e694b6f7f696e737574695a7f7f347e757f347d756c">[email&#160;protected]</a>.
Ms. Melanie Lampton, U.S. Department of Energy, Office of the
General Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC
20585-0121. Telephone: (240) 571-5157. Email:
<a href="/cdn-cgi/l/email-protection#98d5fdf4f9f6f1fdb6d4f9f5e8ecf7f6d8f0e9b6fcf7fdb6fff7ee">[email&#160;protected]</a>.
For further information on how to submit a comment, review other
public comments and the docket, or participate in the public meeting
webinar, contact the Appliance and Equipment Standards Program staff at
(202) 287-1445 or by email: <a href="/cdn-cgi/l/email-protection#74350404181d151a17112700151a101506100725011107001d1b1a073411115a101b115a131b02">[email&#160;protected]</a>.

SUPPLEMENTARY INFORMATION: DOE proposes to maintain a previously
approved incorporation by reference and to incorporate by reference the
following industry standards into parts 429 and 431:
AHRI Standard 340/360-2022 (I-P), 2022 Standard for Performance
Rating of Commercial and Industrial Unitary Air-conditioning and Heat
Pump Equipment, AHRI approved January 26, 2022 (AHRI 340/360-2022).
Copies of AHRI 340/360-2022 can be obtained from the Air-
Conditioning, Heating, and Refrigeration Institute (AHRI), 2311 Wilson
Blvd., Suite 400, Arlington, VA 22201 (703) 524-8800, or online at:
<a href="http://www.ahrinet.org/standards/search-standards">www.ahrinet.org/standards/search-standards</a>.
AHRI Standard 1340(I-P)-202X Draft, Performance Rating of
Commercial and Industrial Unitary Air-conditioning and Heat Pump
Equipment (AHRI 1340-202X Draft). AHRI 1340-202X Draft is in draft form
and its text was provided to DOE for the purposes of review only during
the drafting of this NOPR. If this industry test standard is formally
adopted, DOE intends to incorporate by reference the final published
version of AHRI 1340 in DOE's subsequent test procedure final rule. If
there are substantive changes between the draft and published versions
for which DOE receives stakeholder comments in response to this NOPR
recommending that DOE adopt provisions consistent with the published
version of AHRI 1340, then DOE may consider adopting those provisions.
If there are substantive changes between the draft and published
versions for which

[[Page 56393]]

stakeholder comments do not express support, DOE may adopt the
substance of the AHRI 1340-202X Draft or provide additional opportunity
for comment on the changes to the industry consensus standard.
A copy of the AHRI 1340-202X Draft is provided in the docket for
this rulemaking for review.
ANSI/ASHRAE Standard 37-2009, Methods of Testing for Rating
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment,
ASHRAE approved June 24, 2009 (ANSI/ASHRAE 37-2009).
Copies of ANSI/ASHRAE 37-2009 can be obtained from the American
Society of Heating, Refrigerating and Air-Conditioning Engineers, 180
Technology Parkway, Peachtree Corners, GA 30092, (404) 636-8400, or
online at: <a href="http://www.ashrae.org">www.ashrae.org</a>.
See section IV.M of this document for a further discussion of these
standards.

Table of Contents

I. Authority and Background
A. Authority
B. Background
II. Synopsis of the Notice of Proposed Rulemaking
III. Discussion
A. Scope of Applicability
B. Definitions
1. CUAC and CUHP Definition
2. Basic Model Definition
3. Double-Duct Definition
4. Metric Definitions
C. Updates to Industry Test Standards
1. AHRI 340/360
2. AHRI 1340
3. ASHRAE 37
D. Consideration of the ACUAC and ACUHP Working Group TP Term
Sheet
E. DOE Proposed Test Procedures
F. Efficiency Metrics and Test Conditions
1. Comments Received on Metrics
a. IEER Test Conditions and Weighting Factors
b. Energy Efficiency Metrics for ECUACs and WCUACs
c. Cyclic Degradation Factor for Cooling
d. Economizing and Ventilation
e. External Static Pressure Requirements
f. Damper Leakage, Energy Recovery Systems, and Crankcase
Heaters
g. Controls Verification Procedure
h. Heating Efficiency Metric
2. Test Conditions Used for Current Metrics in Appendix A
3. Test Conditions Used for New Metrics in Proposed Appendix A1
4. IVEC
5. IVHE
a. IVHE for Colder Climates
6. Additions and Revisions to the IVEC and IVHE Metrics Not
Included in the Term Sheet
a. Cooling Weighting Factors Adjustment
b. ESP Testing Target Calculation
c. Test Instructions for Splitting ESP Between Return and Supply
Ductwork
d. Default Fan Power and Maximum Pressure Drop for Coil-Only
Systems
e. Component Power Measurement
f. IVHE Equations
g. Non-Standard Low-Static Indoor Fan Motors
7. Efficiency Metrics for ECUACs and WCUACs
a. Heat Rejection Components for WCUACs
8. Efficiency Metrics for Double-Duct Systems
G. Test Method Changes in AHRI Standard 340/360
1. Vertical Separation of Indoor and Outdoor Units
2. Measurement of Air Conditions
3. Refrigerant Charging Instructions
4. Primary and Secondary Methods for Capacity Measurements
5. Atmospheric Pressure
a. Adjustment for Different Atmospheric Pressure Conditions
b. Minimum Atmospheric Pressure
c. Atmospheric Pressure Measurement
6. Condenser Head Pressure Controls
7. Length of Refrigerant Line Exposed to Outdoor Conditions
8. Indoor Airflow Condition Tolerance
9. ECUACs and WCUACs With Cooling Capacity Less Than 65,000 Btu/
h
10. Additional Test Method Topics for ECUACs
a. Outdoor Air Entering Wet-Bulb Temperature
b. Make-Up Water Temperature
c. Piping Evaporator Condensate to Condenser Sump
d. Purge Water Settings
e. Condenser Spray Pumps
f. Additional Steps To Verify Proper Operation
H. General Comments Received in Response to the July 2017 TP RFI
I. Configuration of Unit Under Test
1. Summary
2. Background
3. Proposed Approach for Exclusion of Certain Components
a. Components Addressed Through Test Provisions of 10 CFR Part
431, Subpart F, appendices A and A1
b. Components Addressed Through Representation Provisions of 10
CFR 429.43
c. Enforcement Provisions of 10 CFR 429.134
d. Testing Specially Built Units That Are Not Distributed in
Commerce
J. Represented Values
1. Cooling Capacity
2. Single-Zone Variable-Air-Volume and Multi-Zone Variable-Air-
Volume
3. Confidence Limit
4. AEDM Tolerance for IVEC and IVHE
5. Minimum Part-Load Airflow
K. Enforcement Procedure for Verifying Cut-In and Cut-Out
Temperatures
L. Proposed Organization of the Regulatory Text for CUACs and
CUHPs
M. Compliance Date
N. Test Procedure Costs and Impact
1. Appendix A
2. Appendix A1
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 12866, 13563 and 14094
B. Review Under the Regulatory Flexibility Act
1. Description of Reasons Why Action Is Being Considered
2. Objectives of, and Legal Basis for, Rule
3. Description and Estimated Number of Small Entities Regulated
4. Description and Estimate of Compliance Requirements
a. Cost and Compliance Associated With Appendix A
b. Cost and Compliance Associated With Appendix A1
5. Duplication, Overlap, and Conflict With Other Rules and
Regulations
6. Significant Alternatives to the Rule
C. Review Under the Paperwork Reduction Act of 1995
D. Review Under the National Environmental Policy Act of 1969
E. Review Under Executive Order 13132
F. Review Under Executive Order 12988
G. Review Under the Unfunded Mandates Reform Act of 1995
H. Review Under the Treasury and General Government
Appropriations Act, 1999
I. Review Under Executive Order 12630
J. Review Under Treasury and General Government Appropriations
Act, 2001
K. Review Under Executive Order 13211
L. Review Under Section 32 of the Federal Energy Administration
Act of 1974
M. Description of Materials Incorporated by Reference
V. Public Participation
A. Participation in the Webinar
B. Procedure for Submitting Prepared General Statements for
Distribution
C. Conduct of the Webinar
D. Submission of Comments
E. Issues on Which DOE Seeks Comment
VI. Approval of the Office of the Secretary

I. Authority and Background

Small, large, and very large commercial package air conditioning
and heating equipment are included in the list of ``covered equipment''
for which DOE is authorized to establish and amend energy conservation
standards and test procedures. (42 U.S.C. 6311(1)(B)-(D)) Commercial
package air conditioning and heating equipment includes as equipment
categories the air-cooled commercial unitary air conditioners with a
rated cooling capacity greater than or equal to 65,000 Btu/h (ACUACs)
and air-cooled commercial unitary heat pumps with a rated cooling
capacity greater than or equal to 65,000 Btu/h (ACUHPs), evaporatively-
cooled commercial unitary air conditioners (ECUACs), and water-cooled
commercial unitary air conditioners (WCUACs), which are the subject of
this NOPR.\1\ (ECUACs,

[[Page 56394]]

WCUACs, and ACUACs and ACUHPs including double-duct equipment are
collectively referred to as CUACs and CUHPs in this document.) The
current DOE test procedures for CUACs and CUHPs are codified at title
10 of the Code of Federal Regulations (CFR) part 431, subpart F,
section 96, Table 1. The following sections discuss DOE's authority to
establish and amend test procedures for CUACs and CUHPs, as well as
relevant background information regarding DOE's proposed amendments to
the test procedures for this equipment.
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\1\ While ACUACs with rated cooling capacity less than 65,000
Btu/h are included in the broader category of CUACs, they are not
addressed in this NOPR. The test procedure for ACUACs with rated
cooling capacity less than 65,000 Btu/h have been addressed in a
separate rulemaking: see Docket No. EERE-2017-BT-TP-0018-0031. All
references within this NOPR to ACUACs and ACUHPs exclude equipment
with rated cooling capacity less than 65,000 Btu/h.
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A. Authority

The Energy Policy and Conservation Act, Public Law 94-163 (42
U.S.C. 6291-6317, as codified), as amended (EPCA),\2\ authorizes DOE to
regulate the energy efficiency of a number of consumer products and
certain industrial equipment. (42 U.S.C. 6291-6317) Title III, Part C
\3\ of EPCA, added by Public Law 95-619, Title IV, section 441(a),
established the Energy Conservation Program for Certain Industrial
Equipment, which sets forth a variety of provisions designed to improve
energy efficiency. This covered equipment includes small, large, and
very large commercial package air conditioning and heating equipment.
(42 U.S.C. 6311(1)(B)-(D)) Commercial package air conditioning and
heating equipment includes CUACs and CUHPs, which are the subject of
this document.
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\2\ All references to EPCA in this document refer to the statute
as amended through the Energy Act of 2020, Public Law 116-260 (Dec.
27, 2020), which reflect the last statutory amendments that impact
Parts A and A-1 of EPCA.
\3\ For editorial reasons, upon codification in the U.S. Code,
Part C was redesignated Part A-1.
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The energy conservation program under EPCA consists essentially of
four parts: (1) testing, (2) labeling, (3) Federal energy conservation
standards, and (4) certification and enforcement procedures. Relevant
provisions of EPCA include definitions (42 U.S.C. 6311), energy
conservation standards (42 U.S.C. 6313), test procedures (42 U.S.C.
6314), labeling provisions (42 U.S.C. 6315), and the authority to
require information and reports from manufacturers (42 U.S.C. 6316; 42
U.S.C. 6296).
The Federal testing requirements consist of test procedures that
manufacturers of covered equipment must use as the basis for: (1)
certifying to DOE that their equipment complies with the applicable
energy conservation standards adopted pursuant to EPCA (42 U.S.C.
6316(b); 42 U.S.C. 6296), and (2) making representations about the
efficiency of that equipment (42 U.S.C. 6314(d)). Similarly, DOE uses
these test procedures to determine whether the equipment complies with
relevant standards promulgated under EPCA.
Federal energy efficiency requirements for covered equipment
established under EPCA generally supersede State laws and regulations
concerning energy conservation testing, labeling, and standards. (42
U.S.C. 6316(a) and (b); 42 U.S.C. 6297) DOE may, however, grant waivers
of Federal preemption in limited circumstances for particular State
laws or regulations, in accordance with the procedures and other
provisions of EPCA. (42 U.S.C. 6316(b)(2)(D))
Under 42 U.S.C. 6314, EPCA also sets forth the general criteria and
procedures DOE is required to follow when prescribing or amending test
procedures for covered equipment. Specifically, EPCA requires that any
test procedure prescribed or amended under this section must be
reasonably designed to produce test results that reflect energy
efficiency, energy use, and estimated operating cost of a given type of
covered equipment (or class thereof) during a representative average
use cycle and requires that such test procedures not be unduly
burdensome to conduct. (42 U.S.C. 6314(a)(2)-(3))
As discussed, CUACs and CUHPs are classified as commercial package
air conditioning and heating equipment. EPCA requires that the test
procedures for commercial package air conditioning and heating
equipment be those generally accepted industry testing procedures or
rating procedures developed or recognized by AHRI or ASHRAE, as
referenced in ASHRAE Standard 90.1, ``Energy Standard for Buildings
Except Low-Rise Residential Buildings'' (ASHRAE Standard 90.1). (42
U.S.C. 6314(a)(4)(A)) Further, if such an industry test procedure is
amended, DOE must update its test procedure to be consistent with the
amended industry test procedure, unless DOE determines, by rule
published in the Federal Register and supported by clear and convincing
evidence, that the amended test procedure would not meet the
requirements in 42 U.S.C. 6314(a)(2) and (3) related to representative
use and test burden, in which case DOE may establish an amended test
procedure that does satisfy those statutory provisions. (42 U.S.C.
6314(a)(4)(B) and (C))
EPCA also requires that, at least once every seven years, DOE
evaluate test procedures for each type of covered equipment, including
CUACs and CUHPs, to determine whether amended test procedures would
more accurately or fully comply with the requirements for the test
procedures to not be unduly burdensome to conduct and be reasonably
designed to produce test results that reflect energy efficiency, energy
use, and estimated operating costs during a representative average use
cycle. (42 U.S.C. 6314(a)(1)-(3))
In addition, if DOE determines that a test procedure amendment is
warranted, the Department must publish proposed test procedures in the
Federal Register and afford interested persons an opportunity (of not
less than 45 days duration) to present oral and written data, views,
and arguments on the proposed test procedures. (42 U.S.C. 6314(b)) If
DOE determines that test procedure revisions are not appropriate, DOE
must publish in the Federal Register its determination not to amend the
test procedures. (42 U.S.C. 6314(a)(1)(A)(ii))
DOE is proposing amendments to the test procedures for CUACs and
CUHPs in satisfaction of its aforementioned statutory obligations under
EPCA. (42 U.S.C. 6314(a)(4)(A)) and (42 U.S.C 6314(a)(1)-(3))

B. Background

DOE's existing test procedure for CUACs and CUHPs appears at 10 CFR
431.96 (Uniform test method for the measurement of energy efficiency of
commercial air conditioners and heat pumps). The test procedure for
ACUACs and ACUHPs with a rated cooling capacity of greater than or
equal to 65,000 Btu/h specified in 10 CFR 431.96 references appendix A
to subpart F of part 431 (Uniform Test Method for the Measurement of
Energy Consumption of Air-Cooled Small (>=65,000 Btu/h), Large, and
Very Large Commercial Package Air Conditioning and Heating Equipment,
referred to as appendix A in this document). Appendix A references
certain sections of ANSI/AHRI Standard 340/360-2007, 2007 Standard for
Performance Rating of Commercial and Industrial Unitary Air-
Conditioning and Heat Pump Equipment, approved by ANSI on October 27,
2011 and updated by addendum 1 in December 2010 and addendum 2 in June
2011 (ANSI/AHRI 340/360-2007); ANSI/ASHRAE Standard 37-2009, Methods of
Testing for Rating Electrically Driven Unitary Air-Conditioning and
Heat Pump Equipment (ANSI/ASHRAE 37-2009); and specifies other test
procedure requirements related to minimum external static pressure
(ESP), optional break-in period, refrigerant charging, setting indoor
airflow, condenser head pressure controls, standard airflow and air
quantity, tolerance on capacity at

[[Page 56395]]

part-load test points, and condenser air inlet temperature for part-
load tests.
The DOE test procedure for ECUACs and WCUACs with a rated cooling
capacity of greater than or equal to 65,000 Btu/h specified in 10 CFR
431.96 incorporates by reference ANSI/AHRI 340/360-2007 (excluding
section 6.3 of ANSI/AHRI 340/360-2007 and including paragraphs (c) and
(e) of Sec. 431.96.\4\) The DOE test procedure for ECUACs and WCUACs
with a rated cooling capacity of less than 65,000 Btu/h incorporates by
reference ANSI/AHRI Standard 210/240-2008, ``2008 Standard for
Performance Rating of Unitary Air-Conditioning & Air-Source Heat Pump
Equipment,'' approved by ANSI on October 27, 2011 and updated by
addendum 1 in June 2011 and addendum 2 in March 2012 (ANSI/AHRI 210/
240-2008).
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\4\ Paragraphs (c) and (e) of 10 CFR 431.96 address optional
break-in provisions and additional provisions regarding set up,
respectively.
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On October 26, 2016, ASHRAE published ASHRAE Standard 90.1-2016,
which included updates to the test procedure references for CUACs and
CUHPs (excluding CUACs and CUHPs with a rated cooling capacity less
than 65,000 Btu/h) to reference AHRI Standard 340/360-2015, 2015
Standard for Performance Rating of Commercial and Industrial Unitary
Air-Conditioning and Heat Pump Equipment (AHRI 340/360-2015).\5\ This
action by ASHRAE triggered DOE's obligations under 42 U.S.C.
6314(a)(4)(B), as outlined previously. On July 25, 2017, DOE published
a request for information (RFI) (July 2017 TP RFI) in the Federal
Register to collect information and data to consider amendments to
DOE's test procedures for certain categories of commercial package air
conditioning and heating equipment including CUACs and CUHPs. 82 FR
34427. As part of the July 2017 TP RFI, DOE identified several aspects
of the currently applicable Federal test procedures for CUACs and CUHPs
that might warrant modifications, in particular: incorporation by
reference of the most recent version of the relevant industry
standard(s); efficiency metrics and calculations; and clarification of
test methods. Id. at 82 FR 34439-34445. DOE also requested comment on
any additional topics that may inform DOE's decisions in a future test
procedure rulemaking, including methods to reduce regulatory burden
while ensuring the procedures' accuracies. Id. at 82 FR 34448.
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\5\ The previous version of ASHRAE Standard 90.1 (i.e., ASHRAE
Standard 90.1-2013) references ANSI/AHRI 340/360-2007.
---------------------------------------------------------------------------

DOE received a number of comments regarding CUACs and CUHPs in
response to the July 2017 TP RFI from interested parties. Table I.1
lists the commenters that provided comments relevant to CUACs and
CUHPs, along with each commenter's abbreviated name used throughout
this NOPR.\6\ Discussion of the relevant comments, and DOE's responses,
are provided in the appropriate sections of this document.
---------------------------------------------------------------------------

\6\ The parenthetical reference provides a reference for
information located in a docket related to DOE's rulemaking to
develop test procedures for CUACs and CUHPs. As noted, the July 2017
RFI addressed a variety of different equipment categories and is
available under docket number EERE-2017-BT-TP-0018, which is
maintained at <a href="http://www.regulations.gov">www.regulations.gov</a>. As this NOPR addresses only CUACs
and CUHPs, it has been assigned a separate docket number (i.e.,
EERE-2022-BT-STD-0015). The references are arranged as follows:
(commenter name, comment docket ID number, page of that document).

Table I.1--List of Commenters With Written Submissions in Response to the July 2017 TP RFI Relevant to CUACs and
CUHPs
----------------------------------------------------------------------------------------------------------------
Comment No. in
Name of commenter Abbreviation used the docket Commenter type
----------------------------------------------------------------------------------------------------------------
Air-Conditioning, Heating, and Refrigeration AHRI.................. 11 Trade Association.
Institute.
Appliance Standards Awareness Project, Alliance ASAP, ASE, et al...... 9 Efficiency Advocacy
to Save Energy, American Council for an Energy- Organizations.
Efficient Economy, Northwest Energy Efficiency
Alliance, and Northwest Power and Conservation
Council.
Carrier Corporation............................. Carrier............... 6 Manufacturer.
Goodman Global Inc.............................. Goodman............... 14 Manufacturer.
Ingersoll Rand.................................. Trane................. 12 Manufacturer.
Lennox International Inc........................ Lennox................ 8 Manufacturer.
National Comfort Institute...................... NCI................... 4 Trade Association.
Pacific Gas and Electric Company, Southern CA IOUs............... 7 Utilities.
California Gas Company, San Diego Gas and
Electric, and Southern California Edison;
(collectively referred to as the ``California
Investor-Owned Utilities'').
----------------------------------------------------------------------------------------------------------------

A parenthetical reference at the end of a comment quotation or
paraphrase provides the location of the item in the public record.\7\
For cases in which this NOPR references comments received in response
to the July 2017 TP RFI (which are contained within a different docket
\8\), the full docket number (rather than just the document number) is
included in the parenthetical reference.
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\7\ The parenthetical reference provides a reference for
information located in the relevant docket, which is maintained at
<a href="http://www.regulations.gov">www.regulations.gov</a>. The references are arranged as follows:
(commenter name, comment docket ID number, page of that document).
\8\ Comments submitted in response to the July 2017 TP RFI are
available in Docket No. EERE-2017-BT-TP-0018.
---------------------------------------------------------------------------

At the time DOE published the July 2017 TP RFI, the applicable
version of ASHRAE Standard 90.1 was the 2016 edition, which referenced
AHRI Standard 340/360-2015, 2015 Standard for Performance Rating of
Commercial and Industrial Unitary Air-Conditioning and Heat Pump
Equipment as the test procedure for CUACs and CUHPs. On October 24,
2019, ASHRAE published ASHRAE Standard 90.1-2019, which updated the
relevant AHRI Standard 340/360 reference to the 2019 edition, 2019
Standard for Performance Rating of Commercial and Industrial Unitary
Air-Conditioning and Heat Pump Equipment (AHRI 340/360-2019). In
January 2022, AHRI published additional updates to its test procedure
standard for CUACs and CUHPs, with the publication of AHRI Standard
340/360-2022, 2022 Standard for Performance Rating of Commercial and
Industrial Unitary Air-conditioning and Heat Pump Equipment (AHRI 340/
360-2022), which DOE is proposing to reference in the amended test
procedure in appendix A to subpart F of 10 CFR part 431 in this NOPR.
These industry test standards are discussed further in section III.C of
this NOPR. To the extent that comments on the July 2017 TP RFI are
still relevant to AHRI 340/360-2022, DOE addresses such comments in the
following sections.

[[Page 56396]]

For ECUACs and WCUACs with a rated cooling capacity less than
65,000 Btu/h, ASHRAE Standard 90.1-2016 references ANSI/AHRI 210/240-
2008. After the publication of the July 2017 RFI, AHRI published AHRI
Standard 210/240-2017, 2017 Standard for Performance Rating of Unitary
Air-conditioning & Air-source Heat Pump Equipment (AHRI 210/240-2017).
ASHRAE Standard 90.1-2019 references AHRI 210/240-2017 as the test
procedure for ECUACs and WCUACs with rated cooling capacities less than
65,000 Btu/h. After the publication of AHRI 210/240-2017, AHRI released
two updates to that industry standard: (1) AHRI Standard 210/240-2017
with Addendum 1, 2017 Standard for Performance Rating of Unitary Air-
conditioning & Air-source Heat Pump Equipment (AHRI 210/240-2017 with
Addendum 1), which was published in April 2019; and (2) AHRI Standard
210/240-2023, 2023 Standard for Performance Rating of Unitary Air-
conditioning & Air-source Heat Pump Equipment (AHRI 210/240-2023),
which was published in May 2020.
On May 12, 2020, DOE published an RFI in the Federal Register
regarding energy conservation standards for ACUACs, ACUHPs, and
commercial warm air furnaces (May 2020 ECS RFI). 85 FR 27941. In
response to the May 2020 ECS RFI, DOE received comments from various
stakeholders, including ones related to the test procedure for ACUACs
and ACUHPs. Table I.2 lists the stakeholders whose comments in response
to the May 2020 ECS RFI were related to the ACUAC and ACUHP test
procedures and have been considered in this rulemaking. For cases in
which this NOPR references comments received in response to the May
2020 ECS RFI (which are contained within a different docket \9\), the
full docket number (rather than just the item entry number) is included
in the parenthetical reference.
---------------------------------------------------------------------------

\9\ Comments submitted in response to the May 2020 ECS RFI are
available in Docket No. EERE-2019-BT-STD-0042.

Table I.2--List of Commenters With Written Submissions in Response to the May 2020 ECS RFI Relevant to CUAC and
CUHP Test Procedures
----------------------------------------------------------------------------------------------------------------
Comment No. in
Name of commenter Abbreviation used the docket Commenter type
----------------------------------------------------------------------------------------------------------------
Appliance Standards Awareness Project, American ASAP, ACEEE, et al.... 23 Efficiency Advocacy
Council for an Energy Efficient Economy, Organizations and
California Energy Commission, Natural Resources State Agency.
Defense Council, and Northeast Energy
Efficiency Partnerships.
Carrier Corporation............................. Carrier............... 13 Manufacturer.
Goodman Manufacturing Company................... Goodman............... 17 Manufacturer.
John Walsh...................................... Walsh................. 18 Individual.
Kristin Heinemeier.............................. Heinemeier............ 12 Individual.
Northwest Energy Efficiency Alliance............ NEEA.................. 24 Efficiency Advocacy
Organization.
Pacific Gas and Electric Company, San Diego Gas CA IOUs............... 20 Utilities.
and Electric, and Southern California Edison;
(collectively referred to as the ``California
Investor-Owned Utilities'').
Trane Technologies.............................. Trane................. 16 Manufacturer.
Verified Inc.................................... Verified.............. 11 Efficiency Advocacy
Organization.
----------------------------------------------------------------------------------------------------------------

On May 25, 2022, DOE published an RFI in the Federal Register
regarding test procedures and energy conservations standards for CUACs
and CUHPs (May 2022 TP/ECS RFI). 87 FR 31743. In response to the May
2022 TP/ECS RFI, DOE notes that it received comments from various
stakeholders related to the test procedure for CUACs and CUHPs. Table
I.3 lists the stakeholders whose comments in response to the May 2022
TP/ECS RFI were related to the CUAC and CUHP test procedures and have
been considered in this proposed rulemaking. For cases in which this
NOPR references comments received in response to the May 2022 TP/ECS
RFI (which are contained within a different docket \10\), the full
docket number (rather than just the item entry number) is included in
the parenthetical reference.
---------------------------------------------------------------------------

\10\ Comments submitted in response to the May 2022 ECS/TP RFI
are available in Docket No. EERE-2022-BT-STD-0015.

Table I.3--List of Commenters With Written Submissions in Response to the May 2022 TP/ECS RFI Relevant to CUAC
and CUHP Test Procedures
----------------------------------------------------------------------------------------------------------------
Comment No. in
Name of commenter Abbreviation used the docket Commenter type
----------------------------------------------------------------------------------------------------------------
Air-Conditioning Heating and Refrigeration AHRI.................. 8 Manufacturer.
Institute.
Appliance Standards Awareness Project, American ASAP and ACEEE........ 11 Efficiency Advocacy
Council for an Energy-Efficient Economy. Organizations.
Carrier Corporation............................. Carrier............... 10 Manufacturer.
Lennox International Inc........................ Lennox................ 9 Manufacturer.
New York State Energy Research and Development NYSERDA............... 7 State Agency.
Authority.
Northwest Energy Efficiency Alliance............ NEEA.................. 13 Efficiency Advocacy
Organization.
Pacific Gas and Electric Company, San Diego Gas CA IOUs............... 12 Utilities.
and Electric, and Southern California Edison;
(collectively referred to as the ``California
Investor-Owned Utilities'').

[[Page 56397]]

Trane Technologies.............................. Trane................. 14 Manufacturer.
----------------------------------------------------------------------------------------------------------------

On July 29, 2022, DOE published in the Federal Register a notice of
intent to establish a working group for commercial unitary air
conditioners and heat pumps (Working Group) to negotiate proposed test
procedures and amended energy conservation standards for this equipment
(July 2022 Notice of Intent). 87 FR 45703. The Working Group was
established under the Appliance Standards and Rulemaking Federal
Advisory Committee (ASRAC) in accordance with the Federal Advisory
Committee Act (FACA) (5 U.S.C App 2) and the Negotiated Rulemaking Act
(NRA) (5 U.S.C. 561-570, Pub. L. 104-320). The purpose of the Working
Group was to discuss, and if possible, reach consensus on recommended
amendments to the test procedures and energy conservation standards for
ACUACs and ACUHPs. The Working Group consisted of 14 voting members,
including DOE. (See appendix A, Working Group Members, Document No. 65
in Docket No. EERE-2022-BT-STD-0015) On December 15, 2022, the Working
Group signed a term sheet of recommendations regarding ACUAC and ACUHP
test procedures to be submitted to ASRAC, the contents of which are
referenced throughout this NOPR (referred to hereafter as the ACUAC and
ACUHP Working Group TP Term Sheet). (See Id.) The ACUAC and ACUHP
Working Group TP Term Sheet was approved by ASRAC on March 2, 2023.
These recommendations are discussed further in section III.D of this
NOPR.
In January 2023, ASHRAE published ASHRAE Standard 90.1-2022, which
included updates to the test procedure references for CUACs and CUHPs
with cooling capacities greater than or equal to 65,000 Btu/h,
specifically referencing AHRI 340/360-2022. For ECUACs and WCUACs with
capacities less than 65,000 Btu/h, ASHRAE Standard 90.1-2022 references
AHRI 210/240-2023.
Notably, ECUACs and WCUACs with a rated cooling capacity less than
65,000 Btu/h were removed from the scope of AHRI 210/240-2023, and are
instead included in the scope of AHRI 340/360-2022. DOE discusses this
change in scope to the industry test procedure and comments received
related to ECUACs and WCUACs with a cooling capacity less than 65,000
Btu/h in section III.G.9 of this NOPR.
Following the publication of ASHRAE Standard 90.1-2022, AHRI is
currently working on an update to the AHRI standard 340/360 \11\ (i.e.,
AHRI Standard 1340(I-P)-202X Draft, Performance Rating of Commercial
and Industrial Unitary Air-conditioning and Heat Pump Equipment (AHRI
1340-202X Draft)).
---------------------------------------------------------------------------

\11\ DOE has provided a copy of AHRI 1340-202X Draft in the
docket for this rulemaking, available at <a href="http://www.regulations.gov/docket/EERE-2023-BT-TP-0014">www.regulations.gov/docket/EERE-2023-BT-TP-0014</a>. AHRI Standard 1340 is in draft form and its
text was provided to DOE for the purposes of review only during the
drafting of this NOPR. Note that the draft AHRI Standard 1340 may be
further revised, edited, delayed, or withdrawn prior to publication
by the AHRI Standards Technical Committee (STC).
---------------------------------------------------------------------------

II. Synopsis of the Notice of Proposed Rulemaking

In this NOPR, DOE proposes to update its test procedures for CUACs
and CUHPs by: (1) updating the reference in the Federal test procedure
to the most recent version of the industry test procedure, AHRI 340/
360-2022, for measuring integrated energy efficiency ratio (IEER),
energy efficiency ratio (EER), and coefficient of performance (COP);
and (2) establishing a new test procedure that references the most
recent draft version of industry test procedure, AHRI 1340-202X Draft,
and is consistent with recommendations from the ACUAC and ACUHP Working
Group TP Term Sheet that DOE should include new efficiency metrics
(integrated ventilation, economizer, and cooling (IVEC) and integrated
ventilation and heating efficiency (IVHE)) and new testing
requirements. If a finalized version of AHRI 1340-202X Draft is not
published before the final rule or if there are substantive changes
between the draft and published versions of AHRI 340/360, DOE may adopt
the substance of the AHRI 1340-202X Draft or provide additional
opportunity for comment on the final version of that industry consensus
standard.
To implement the proposed changes, DOE proposes: (1) to amend
appendix A to incorporate by reference AHRI 340/360-2022 for CUACs and
CUHPs, while maintaining the current efficiency metrics; and (2) to add
a new appendix A1 to subpart F of 10 CFR part 431. At 10 CFR part
431.96, ``Uniform test method for the measurement of energy efficiency
of commercial air conditioners and heat pumps,'' DOE would list
appendix A1 as the applicable test method for CUACs and CUHPs for any
standards denominated in terms of IVEC and IVHE. Appendix A1 would
utilize the AHRI 1340-202X Draft, including the new IVEC and IVHE
efficiency metrics recommended by the ACUAC and ACUHP Working Group TP
Term Sheet. Use of appendix A1 would not be required until such time as
compliance is required with any amended energy conservation standard
based on the new metrics, should DOE adopt such standards. After the
date on which compliance with appendix A1 would be required, appendix A
would no longer be used as part of the Federal test procedure. DOE is
also proposing more general updates to establish a definition for the
terms ``commercial unitary air conditioner'' and ``commercial unitary
heat pump.'' Lastly, DOE is proposing to amend certain provisions
within DOE's regulations for representation and enforcement consistent
with the proposed test procedure amendments.
Table I.1 summarizes the current DOE test procedure for CUACs and
CUHPs, DOE's proposed changes to that test procedure, and the reason
for each proposed change.

[[Page 56398]]

Table II.1--Summary of Changes in Proposed Test Procedure Relative to
Current Test Procedure
------------------------------------------------------------------------
Proposed test
Current DOE test procedure procedure Attribution
------------------------------------------------------------------------
Incorporates by reference..... Incorporate by Update to the
1. ANSI/AHRI 340/360-2007 for reference AHRI 340/ most recent
CUACs and CUHPs with a 360-2022 and ANSI/ industry test
cooling capacity greater than ASHRAE 37-2009 in procedures.
or equal to 65,000 Btu/h; and. appendix A. Utilize
2. ANSI/AHRI 210/240-2008 for AHRI 1340-202X Draft
ECUACs and WCUACs with a and incorporate by
cooling capacity less than reference ANSI/ASHRAE
65,000 Btu/h. 37-2009 in a new
appendix A1.
Includes provisions for Appendix A maintains Updates to the
determining EER, IEER, and provisions for applicable
COP. determining EER, industry test
IEER, and COP. procedures.
Appendix A1 includes
provisions for
determining EER2,
COP2, IVEC, and IVHE.
Does not include certain CUAC Includes provisions in Improve
and CUHP provisions regarding 10 CFR 429.43 representativen
over-rating capacity and specific to CUACs and ess of test
specific components for CUHPs to determine procedure.
determination of represented represented values
values in 10 CFR 429.43. for units with
specific components,
and to prevent
cooling capacity over-
rating.
Does not include certain CUAC- Adopts product- Clarify how DOE
and CUHP-specific enforcement specific enforcement will conduct
provisions in 10 CFR 429.134. provisions for CUACs enforcement
and CUHPs regarding: testing.
(1) verification of
cooling capacity for
determining ESP
requirements and (2)
testing of units with
specific components.
------------------------------------------------------------------------

Should DOE adopt the amendments described in this proposed rule,
the effective date for the amended test procedure would be 30 days
after publication of the test procedure final rule in the Federal
Register.
DOE has tentatively determined that the proposed amendments to the
CUAC and CUHP test procedures would not be unduly burdensome.
Furthermore, DOE has tentatively determined that the proposed
amendments to appendix A, if made final, would not alter the measured
efficiency of CUACs and CUHPs or require retesting or recertification
solely as a result of DOE's adoption of the proposed amendments to the
test procedure. Additionally, DOE has tentatively determined that the
proposed amendments to appendix A, if made final, would not increase
the cost of testing. If finalized, representations of energy use or
energy efficiency would be required to be based on testing in
accordance with the amended test procedure in appendix A beginning 360
days after the date of publication of the test procedure final rule in
the Federal Register.
DOE has tentatively determined, however, that the newly proposed
test procedure at appendix A1 would alter the measured efficiency of
CUACs and CUHPs, in part because the amended test procedure would adopt
different energy efficiency metrics than in the current test procedure.
DOE has tentatively determined that the proposed amendments to appendix
A1, if made final, would increase the cost of testing relative to the
current test procedure. Tentative cost estimates are discussed in
section III.M of this document. As discussed, use of appendix A1 would
not be required until the compliance date of any amended energy
conservation standard denominated in terms of the new metrics in
appendix A1, should DOE adopt such standards.
The proposed amendments to representation requirements in 10 CFR
429.43 would not be required until 360 days after publication in the
Federal Register of a test procedure final rule.
Discussion of DOE's proposed actions are addressed in detail in
section III of this NOPR.

III. Discussion

In the following sections, DOE proposes certain amendments to its
test procedures for CUACs and CUHPs. For each proposed amendment, DOE
provides relevant background information, explains why the amendment
merits consideration, discusses relevant public comments, and proposes
a potential approach.

A. Scope of Applicability

This rulemaking applies to ACUACs and ACUHPs with a rated cooling
capacity greater than or equal to 65,000 Btu/h, including double-duct
air conditioners and heat pumps, as well as ECUACs and WCUACs of all
capacities. Definitions that apply to CUACs and CUHPs are discussed in
section III.B of this NOPR.
DOE's regulations for CUACs and CUHPs cover both single-package
units and split systems. See the definition of ``commercial package
air-conditioning and heating equipment'' at 10 CFR 431.92. A split
system consists of a condensing unit--which includes a condenser coil,
condenser fan and motor, and compressor--that is paired with a separate
component that includes an evaporator coil to form a complete
refrigeration circuit for space conditioning. One application for
condensing units is to be paired with an air handler (which includes an
evaporator coil), such that the combined system (i.e., the condensing
unit with air handler) meets the definition of a split system CUAC or
CUHP. It should be pointed out that AHRI has a certification program
for unitary large equipment that includes certification of CUACs,
CUHPs, and condensing units. DOE notes that as part of the AHRI
certification program for unitary large equipment, manufacturers who
sell air-cooled condensing units with a rated cooling capacity greater
than or equal to 65,000 Btu/h and less than 135,000 Btu/h must certify
condensing units as a complete system (i.e., paired with an air
handler) according to the AHRI 340/360 test procedure.\12\ However, for
condensing units with a rated cooling capacity greater than or equal to
135,000 Btu/h and less than 250,000 Btu/h, the AHRI certification
program allows manufacturers to certify condensing units as a complete
system according to AHRI 340/360 or optionally certify as a condensing
unit only according to AHRI Standard 365, ``Standard for Performance
Rating of Commercial and Industrial Unitary Air-Conditioning Condensing
Units'' (AHRI 365). DOE emphasizes that these AHRI testing and
certification requirements differ from the Federal test procedure at 10
CFR 431.96, which requires testing to ANSI/AHRI 340/360-2007 and does
not permit certifying to DOE as a condensing unit only according to
AHRI 365. Additionally, the AHRI

[[Page 56399]]

certification program does not include unitary split systems or
condensing units with cooling capacities above 250,000 Btu/h, whereas
the Federal test procedure and standards (codified at 10 CFR 431.96 and
10 CFR 431.97, respectively) cover all CUACs and CUHPs with cooling
capacities up to 760,000 Btu/h. Once again, DOE emphasizes that
condensing unit models distributed in commerce with air handlers with
cooling capacities up to 760,000 Btu/h are covered as commercial
package air-conditioning and heating equipment (see definition at 10
CFR 431.92) and as such are subject to the Federal regulations
specified for CUACs and CUHPs regarding test procedures (10 CFR
431.96), energy conservation standards (10 CFR 431.97), and
certification and representation requirements (10 CFR 429.43).
---------------------------------------------------------------------------

\12\ See appendix A of the AHRI Unitary Large Equipment
Certification Program Operations Manual (January 2021). This can be
found at <a href="https://www.ahrinet.org/sites/default/files/2022-08/ULE_OM.pdf">https://www.ahrinet.org/sites/default/files/2022-08/ULE_OM.pdf</a>.
---------------------------------------------------------------------------

B. Definitions

1. CUAC and CUHP Definition
In the May 2020 ECS RFI, DOE requested comment on whether the
definitions that apply to CUACs and CUHPs (including the definitions
for small, large, and very large commercial package air conditioning
and heating equipment) require any revisions--and if so, how those
definitions should be revised. 85 FR 27941, 27945 (May 12, 2020). DOE
also requested comment on whether additional equipment definitions are
necessary to close any potential gaps in coverage between equipment
types. Id.
Trane commented that the overall definition for commercial package
air conditioning and heating equipment is very broad and covers
equipment that is used in specific industrial applications (e.g.,
computer room air conditioners (CRACs), dedicated outdoor air systems
(DOASes), and indoor agricultural systems) for which the CUAC/CUHP test
procedure and IEER metric should not apply.\13\ Trane recommended that
DOE should separately regulate these categories of equipment with
specific definitions, test procedures, and energy conservation
standards. (Trane, EERE-2019-BT-STD-0042-0016, pp. 2-3)
---------------------------------------------------------------------------

\13\ The IEER metric represents a weighted average of full-load
and part-load efficiencies, weighted according to the average amount
of time operating at each load point. Additionally, IEER
incorporates reduced condenser temperatures (i.e., reduced outdoor
ambient temperatures) for part-load operation.
---------------------------------------------------------------------------

Goodman commented that ambiguity exists regarding DOASes used for
dry-climate applications, as these systems could be rated and tested in
accordance with AHRI Standard 340/360, as well as AHRI Standard 920,
and that updating definitions to address these specific system types
based on mixed-air or 100-percent air applications would provide some
clarity in the marketplace. (Goodman, EERE-2019-BT-STD-0042-0017, p. 2)
Regarding DOASes, in a final rule published in the Federal Register
on July 27, 2022, DOE defined a direct expansion-dedicated outdoor air
system (DX-DOAS) as a unitary dedicated outdoor air system that is
capable of dehumidifying air to a 55 [deg]F dew point--when operating
under Standard Rating Condition A as specified in Table 4 or Table 5 of
AHRI 920-2020 (incorporated by reference, 10 CFR 431.95) with a
barometric pressure of 29.92 in Hg--for any part of the range of
airflow rates advertised in manufacturer materials, and has a moisture
removal capacity of less than 324 lb/h. 87 FR 45164, 45170, 45198. DOE
has tentatively concluded that this definition provides the requisite
specificity sought by Goodman's comment.
More broadly, as in this NOPR, DOE has previously used the
colloquial terms ``commercial unitary air conditioners'' and
``commercial unitary heat pump'' (i.e., CUACs and CUHPs), to refer to
certain commercial package air conditioning and heating equipment,
recognizing that CUAC is not a statutory term and is not currently used
in the CFR. See 79 FR 58948, 58950 (Sept. 30, 2014); 80 FR 52676, 52676
(Sept. 1, 2015). As codified in regulation, the classes for which EPCA
prescribed standards have been grouped under the headings ``commercial
air conditioners and heat pumps'' (10 CFR 431.96, Table 1) and ``air
conditioning and heating equipment'' (10 CFR 431.97, Table 1), although
these are not defined terms. These classes have also been identified by
the broader equipment type with which they are associated (i.e., small,
large, or very large commercial package air conditioning and heating
equipment). Id. DOE agrees with the commenters that a more tailored
definition regarding the equipment categories covered by these umbrella
terms may provide additional benefits in terms of clarity.
Consequently, in this NOPR, DOE proposes to establish a definition
for ``commercial unitary air conditioner and commercial unitary heat
pump'' to assist in distinguishing between the regulated categories of
commercial package air conditioning and heating equipment. The proposed
definition is structured to indicate categories of commercial package
air conditioning and heating equipment that are excluded from the
definition, rather than stipulating features or characteristics of
CUACs and CUHPs. Specifically, the proposed definition would exclude
single package vertical air conditioners and heat pumps (SPVUs),
variable refrigerant flow multi-split air conditioners and heat pumps,
and water-source heat pumps. To the extent that a unit could be
considered either a CUAC or a CRAC, such unit would be excluded from
the CUAC definition if marketed solely for applications specific to the
CRAC equipment category. To the extent that a unit could be either a
CUAC or a DX-DOAS, such unit would be excluded from the CUAC definition
if it is only capable of providing ventilation and conditioning of 100-
percent outdoor air or it is marketed in all materials as only having
such capability. DOE notes that, when gathering information for
potential enforcement of CRAC, CUAC or a DX-DOAS standards, DOE may
consider marketing materials claiming that a unit is a CRAC, CUAC or
DX-DOAS by any party. Any marketing, by any party, could signal that a
unit is not only a CRAC, CUAC, or a DX-DOAS. DOE notes that to the
extent that a basic model is covered under more than one equipment
category (e.g., CRAC and CUAC) it would be subject to the regulations
applicable to each equipment class that covers that basic model.
DOE proposes the following definition: Commercial unitary air
conditioner and commercial unitary heat pump means any small, large, or
very large air-cooled, water-cooled, or evaporatively-cooled commercial
package air conditioning and heating equipment that consists of one or
more factory-made assemblies that provide space conditioning; but does
not include:
(1) single package vertical air conditioners and heat pumps,
(2) variable refrigerant flow multi-split air conditioners and heat
pumps,
(3) water-source heat pumps;
(4) equipment marketed only for use in computer rooms, data
processing rooms, or other information technology cooling applications,
and
(5) equipment only capable of providing ventilation and
conditioning of 100-percent outdoor air marketed only for ventilation
and conditioning of 100-percent outdoor air.
DOE recognizes that there may be models on the market that would be
covered by DOE regulations for multiple equipment categories. As
discussed in a previous notice addressing CRACs, such models would have
to be tested and rated according to the requirements for each
applicable equipment class of

[[Page 56400]]

standards (e.g., CRAC and CUAC). See 77 FR 16769, 16773 (March 22,
2012).
Issue 1: DOE seeks comment on its proposed definition for CUACs and
CUHPs.
2. Basic Model Definition
The current definition for ``basic model'' in DOE's regulations
includes a provision applicable for ``small, large, and very large air-
cooled or water-cooled commercial package air conditioning and heating
equipment (excluding air-cooled, three-phase, small commercial package
air conditioning and heating equipment with a cooling capacity of less
than 65,000 Btu/h).'' 10 CFR 431.92. Consistent with DOE's proposed
definition for ``commercial unitary air conditioner and commercial
unitary heat pump,'' DOE proposes to similarly update the definition of
``basic model'' so that this provision instead applies to the proposed
term ``commercial unitary air conditioner and commercial unitary heat
pump.'' DOE notes that the term in the current ``basic model''
definition includes ACUACs, ACUHPs, and WCUACs, but does not explicitly
include ECUACs, (DOE notes that the definition of ``commercial package
air-conditioning and heating equipment'' at 10 CFR 431.92 makes clear
that that term includes evaporatively-cooled equipment. Consequently,
ECUACs are clearly part of the relevant basic model definition, so the
omission of the term ``evaporatively-cooled'' from the heading should
not impact the proper functioning and use of the test procedure.
However, DOE is proposing to update the relevant heading to dispel any
confusion in that regard.) This proposal thereby includes ECUACs in
this provision of the ``basic model'' definition--i.e., because ECUACs
are included within the proposed term ``commercial unitary air
conditioner and commercial unitary heat pump,'' as discussed in section
III.B.1 of this NOPR. It would further clarify that this provision of
the ``basic model'' definition refers only to CUACs and CUHPs, and not
to any other category of equipment that is ``small, large, and very
large commercial package air conditioning and heating equipment''.
DOE also proposes editorial changes more generally to the
definition of ``basic model'' specified in 10 CFR 431.92. The current
definition begins with ``Basic model includes'' and each equipment
category-specific provision of the definition begins with the equipment
category name, followed by the word ``means,'' followed by the basic
model definition for that category (e.g., ``Computer room air
conditioners means all units . . .''). However, this wording could be
misinterpreted to read as a definition of each equipment category,
rather than as the definition of what constitutes a basic model for
each equipment category. Therefore, DOE proposes to revise the
definition to instead begin with ``Basic model means'' and then revise
each equipment category specific provision to begin with ``For'' and
replace the word ``means'' with a colon (e.g., ``For Computer room air
conditioners: all units . . .''). These proposed changes to the basic
model definition are editorial and would not change the current
understanding of what constitutes a basic model for each equipment
category.
3. Double-Duct Definition
DOE established a definition for ``double-duct air conditioner or
heat pump'' at 10 CFR 431.92 (referred to as ``double-duct air
conditioners and heat pumps'' or ``double-duct systems'') in an energy
conservation standards direct final rule published in the Federal
Register on January 15, 2016 (January 2016 Direct Final Rule). 81 FR
2420, 2529. This definition was included in a term sheet by the ASRAC
working group for commercial package air conditioners (Commercial
Package Air Conditioners Working Group) as part of the rulemaking that
culminated with the January 2016 Direct Final Rule. (See Document No.
93 in Docket No. EERE-2013-BT-STD-0007, pp. 4-5) DOE defines double-
duct systems as air-cooled commercial package air conditioning and
heating equipment that: (1) Is either a horizontal single package or
split-system unit; or a vertical unit that consists of two components
that may be shipped or installed either connected or split; (2) Is
intended for indoor installation with ducting of outdoor air from the
building exterior to and from the unit, as evidenced by the unit and/or
all of its components being non-weatherized, including the absence of
any marking (or listing) indicating compliance with UL 1995,\14\
``Heating and Cooling Equipment,'' or any other equivalent requirements
for outdoor use; (3) If it is a horizontal unit, a complete unit has a
maximum height of 35 inches; if it is a vertical unit, a complete unit
has a maximum depth of 35 inches; and (4) Has a rated cooling capacity
greater than or equal to 65,000 Btu/h and up to 300,000 Btu/h. 10 CFR
431.92.
---------------------------------------------------------------------------

\14\ Underwriters Laboratory (UL) 1995, UL Standard for Safety
for Heating and Cooling Equipment (UL 1995).
---------------------------------------------------------------------------

In the May 2020 ECS RFI, DOE requested comment on whether the
definitions that apply to ACUACs and ACUHPs, including double-duct
systems, require any revisions--and if so, how those definitions should
be revised. 85 FR 27941, 27945. (May 12, 2020).
In response to the May 2020 ECS RFI, Carrier recommended that DOE
review the current definitions for double-duct systems, as well as the
definition for SPVUs, asserting that the current definitions for
double-duct systems and SPVUs do not clearly delineate the two
equipment categories. Carrier stated that while double-duct systems and
SPVUs are extraordinarily similar in application, double-duct systems
have longer ductwork to bring air from outside the building to the
condensing section of the unit, whereas SPVUs must remain in close
proximately to an exterior wall. (Carrier, EERE-2019-BT-STD-0042-0013
at p. 2)
In response, DOE notes that section 3.7 of AHRI 340/360-2022 and
section 3.12 of the AHRI 1340-202X Draft specify the following
definition for double-duct systems: an air conditioner or heat pump
that complies with all of the following: (1) Is either a horizontal
single package or split-system unit; or a vertical unit that consists
of two components that can be shipped or installed either connected or
split; or a vertical single packaged unit that is not intended for
exterior mounting on, adjacent interior to, or through an outside wall;
(2) Is intended for indoor installation with ducting of outdoor air
from the building exterior to and from the unit, where the unit and/or
all of its components are non-weatherized; (3) If it is a horizontal
unit, the complete unit shall have a maximum height of 35 in. or the
unit shall have components that do not exceed a maximum height of 35
in. If it is a vertical unit, the complete (split, connected, or
assembled) unit shall have components that do not exceed maximum depth
of 35 in.; (4) Has a rated cooling capacity greater than and equal to
65,000 Btu/h and less than or equal to 300,000 Btu/h.
In comparison to DOE's definition, DOE notes the following
regarding the definition for double-duct system in section 3.7 of AHRI
340/360-2022 and section 3.12 of the AHRI 1340-202X Draft: (1) vertical
single packaged units not intended for exterior mounting on, adjacent
interior to, or through an outside wall can be classified as double-
duct systems; (2) the maximum dimensions apply to each component of a
split system; and (3) the AHRI 340/360-2022 and AHRI 1340-202X Draft
definition does not include compliance with UL 1995 as a criterion for
determining whether a model is non-

[[Page 56401]]

weatherized. For the reasons discussed in the following paragraphs, DOE
has tentatively concluded that the definition for double-duct system in
section 3.7 of AHRI 340/360-2022 and section 3.12 of the AHRI 1340-202X
Draft more appropriately classifies double-duct systems and
differentiates this equipment from other categories of commercial
package air conditioning and heating equipment.
Regarding vertical single package units, the DOE definitions for
SPVUs at 10 CFR 431.92 include models that are intended for exterior
mounting on, adjacent interior to, or through an outside wall. In the
January 2016 Direct Final Rule, DOE agreed with the exclusion of
vertical single package units from the definition for ``double-duct
system'' because SPVUs are separately regulated.\15\ 81 FR 2420, 2446
(Jan. 15, 2016). However, the exclusion of all vertical single package
units from the definition for ``double-duct system'' adopted in the
January 2016 Direct Final Rule means that vertical single package
models that do not meet the SPVU definition (i.e., are not intended for
exterior mounting on, adjacent interior to, or through an outside wall)
are not explicitly covered by the definitions for SPVUs or double-duct
systems. Because the reasoning provided in the January 2016 Direct
Final Rule was to exclude SPVUs from the double-duct definition, DOE
has tentatively concluded that vertical single package units that do
not meet the SPVU definition were inadvertently excluded from the DOE
double-duct definition. Therefore, DOE has tentatively determined that
the clarification in the AHRI 340/360-2022 definition for ``double-duct
systems'' (i.e., inclusion of vertical single package units not
intended for exterior mounting on, adjacent interior to, or through an
outside wall) is appropriate and consistent with the intent of the
Commercial Package Air Conditioners Working Group that initially
drafted the current ``double-duct system'' definition. See 81 FR 2420,
2446. (Jan. 15, 2016). This clarification also addresses Carrier's
concern that the current definitions do not clearly differentiate
double-duct systems from SPVUs.
---------------------------------------------------------------------------

\15\ Specifically, DOE stated in the January 2016 Direct Final
Rule that single package vertical units are already covered under
separate standards (10 CFR 431.97(d)). As a result, to ensure that
SPVUs are not covered under the definition of double-duct equipment,
DOE agrees with the ASRAC Term Sheet recommendations that for
vertical double-duct units, only those with split configurations
(that may be installed with the two components attached together)
should be included as part of this separate equipment class.
---------------------------------------------------------------------------

Regarding maximum height and depth dimensions, the revised
definition in section 3.7 of AHRI 340/360-2022 and section 3.12 of the
AHRI 1340-202X draft specifies that for systems with multiple
components, the maximum dimensions apply to each component of the unit.
Because split systems are installed separately from each other, DOE has
tentatively concluded that it is appropriate for the maximum dimensions
for split systems to apply to each component, rather than the combined
system.
Regarding determination of whether a model is non-weatherized, the
AHRI 340/360-2022 and AHRI 1340-202X Draft definition does not include
the criterion regarding the absence of any marking (or listing)
indicating compliance with UL 1995 as an indication that the unit is
intended for indoor installation. Upon examination of UL 1995, DOE
recognizes that the scope of the standard is not limited to models
intended for outdoor installation, and therefore, that compliance with
UL 1995 does not necessarily indicate that a model is intended for
outdoor installation and/or is weatherized. Therefore, DOE tentatively
agrees with removing the reference to UL 1995 in the double-duct
definition, and instead specifying that double-duct systems are
intended for indoor installation (e.g., the unit and/or all of its
components are non-weatherized).
Based on the preceding discussion, DOE has tentatively determined
that the definition for ``double-duct system'' in AHRI 340/360-2022 and
the AHRI 1340-202X Draft better implements the intent of DOE and the
Commercial Package Air Conditioners Working Group to create a separate
equipment class of ACUACs and ACUHPs that are designed for indoor
installation and that would require ducting of outdoor air from the
building exterior. 81 FR 2420, 2446 (Jan. 15, 2016). Thus, DOE is
proposing to revise the definition of double-duct air conditioners and
heat pumps in 10 CFR 431.92 to reflect the updated definition for
double-duct systems in section 3.7 of AHRI 340/360-2022 and section
3.12 of the AHRI 1340-202X Draft.
4. Metric Definitions
As mentioned in section II and discussed in further detail in
sections III.F.4 and III.F.5 of this NOPR, DOE is proposing to adopt
new cooling and heating metrics in appendix A1 (i.e., IVEC and IVHE).
Additionally, DOE is proposing three metrics for optional
representations in appendix A1, as discussed further in section III.F.3
of this NOPR: energy efficiency ratio 2 (EER2), coefficient of
performance 2 (COP2), and IVHE for colder climates (IVHE<INF>C</INF>).
Consistent with this approach, DOE is proposing to add new definitions
for the terms ``IVEC,'' ``IVHE,'' ``EER2,'' and ``COP2'' to 10 CFR
431.92. The proposed definitions describe what each metric represents,
the test procedure used to determine each metric, and specific
designations applicable to each metric (e.g., IVHE<INF>C</INF>).

C. Updates to Industry Test Standards

The following sections discuss the changes included in the most
recent updates to AHRI 340/360 and ASHRAE 37, which are incorporated by
reference in the current DOE test procedure for ACUACs and ACUHPs with
a rated cooling capacity greater than or equal to 65,000 Btu/h at 10
CFR 431.96 and 10 CFR part 431, subpart F, appendix A. AHRI 340/360 is
also incorporated by reference in the current DOE test procedure for
ECUACs and WCUACs with a rated cooling capacity greater than or equal
to 65,000 Btu/h at 10 CFR 431.96.
1. AHRI 340/360
As noted previously, DOE's current test procedures for ACUACs,
ACUHPs, and ECUACs and WCUACs with a rated cooling capacity greater
than or equal to 65,000 Btu/h incorporates by reference ANSI/AHRI 340/
360-2007. DOE's current test procedure for ECUACs and WCUACs with a
rated cooling capacity less than 65,000 Btu/h incorporates by reference
ANSI/AHRI 210/240-2008.
The most recent version of ASHRAE Standard 90.1, (i.e., ASHRAE
Standard 90.1-2022), references AHRI 340/360-2022 as the test procedure
for ACUACs, ACUHPs, and ECUACs and WCUACs with a rated cooling capacity
greater than or equal to 65,000 Btu/h. ASHRAE Standard 90.1-2022
included updates to the test procedure references for ECUACs and WCUACs
with capacities less than 65,000 Btu/h to reference AHRI 210/240-2023.
However, ECUACs and WCUACs with capacities less than 65,000 Btu/h are
outside of the scope of AHRI 210/240-2023 and are instead included in
AHRI 340/360-2022. Given these changes to the relevant industry test
standards, DOE believes that such reference was an oversight.
The following list includes substantive additions in AHRI 340/360-
2022 as compared to ANSI/AHRI 340/360-2007, which is edition referenced
in the current Federal test procedure and applies to CUACs and CUHPs:
1. A method for testing double-duct systems at non-zero ESP (see
section

[[Page 56402]]

6.1.3.7 and appendix I of AHRI 340/360-2022);
2. A method for comparing relative efficiency of indoor integrated
fan and motor combinations (IFMs) that allows CUACs and CUHPs with non-
standard (i.e., higher ESP) IFMs to be rated in the same basic model as
otherwise identical models with standards IFMs (see section D4.2 of
Appendix D of AHRI 340/360-2022);
3. Requirements for indoor and outdoor air condition measurement
(see appendix C of AHRI 340/360-2022);
4. Detailed provisions for setting indoor airflow and ESP (see
sections 6.1.3.4-6.1.3.6 of AHRI 340/360-2022) and refrigerant charging
instructions to be used in cases in which manufacturer's instructions
conflict or are incomplete (see section 5.8 of AHRI 340/360-2022); and
5. ECUACs and WCUACs with cooling capacities less than 65,000 Btu/h
are included within the scope of the standard.
As discussed, DOE is proposing to amend its test procedure for
CUACs and CUHPs by incorporating by reference AHRI 340/360-2022 in
appendix A.
2. AHRI 1340
The recommendations of the ACUAC and ACUHP Working Group TP Term
Sheet are being incorporated into an updated version of AHRI 340/360
currently being drafted (i.e., AHRI 1340-202X Draft) that will
supersede AHRI 340/360-2022.
The AHRI 1340-202X Draft includes recommendations from the ACUAC
and ACUHP Working Group TP Term Sheet described in section III.D of
this NOPR (including the IVEC and IVHE metrics). The AHRI 1340-202X
Draft also includes the following revisions and additions to the IVEC
and IVHE metrics not included in the ACUAC and ACUHP Working Group TP
Term Sheet, which are discussed in detail in sections III.F.5.a,
III.F.6, and III.F.7.a of this NOPR:
1. Detailed test instructions for splitting ESP between the return
and supply ductwork, consistent with ESP requirements recommended in
the ACUAC and ACUHP Working Group TP Term Sheet;
2. Corrections to the hour-based IVEC weighting factors included in
the ACUAC and ACUHP Working Group TP Term Sheet;
3. Correction of the equation in the ACUAC and ACUHP Working Group
TP Term Sheet for calculating adjusted ESP for any cooling or heating
tests conducted with an airflow rate that differs from the full-load
cooling airflow;
4. Addition of separate hour-based weighting factors and bin
temperatures to calculate a separate version of IVHE that is
representative of colder climates, designated IVHEC
5. Changes to the default fan power and maximum pressure drop used
for testing coil-only systems;
6. Additional instruction for component power measurement during
testing;
7. Corrections to equations used for calculating IVHE;
8. Provisions for testing with non-standard low-static indoor fan
motors; and
9. Revision to the power adder for WCUACs that reflects power that
would be consumed by field-installed heat rejection components.
In this NOPR, DOE proposes to incorporate by reference the AHRI
1340-202X Draft in its appendix A1 test procedure. AHRI Standard 1340
is in draft form and its text was provided to DOE for the purposes of
review for this NOPR. Note that the draft AHRI Standard 1340 may be
further revised, edited, delayed, or withdrawn prior to publication by
the AHRI Standards Technical Committee. If AHRI has published a final
version, DOE intends to update its incorporation by reference to the
final published version of AHRI 1340, unless there are substantive
changes between the draft and published versions, in which case DOE may
adopt the substance of the AHRI 1340-202X Draft or provide additional
opportunity for comment on the changes to the industry consensus
standard.
3. ASHRAE 37
ANSI/ASHRAE 37-2009, which provides a method of test for many
categories of air conditioning and heating equipment, is referenced for
testing CUACs and CUHPs by both AHRI 340/360-2022 and the AHRI 1340-
202X Draft. More specifically, sections 5 and 6 and appendices C, D,
and E of AHRI 340/360-2022 and sections 5 and 6 and appendices C, D,
and E of the AHRI 1340-202X Draft reference methods of test in ANSI/
ASHRAE 37-2009. DOE currently incorporates by reference ANSI/ASHRAE 37-
2009 in 10 CFR 431.95, and the current incorporation by reference
applies to the current Federal test procedure for ACUACs and ACUHPs
specified at appendix A. The current Federal test procedures at 10 CFR
431.96 for ECUACs and WCUACs do not explicitly reference ANSI/ASHRAE
37-2009. Given that DOE is proposing to expand the scope of appendix A
to include testing of ECUACs and WCUACs as well as the fact that AHRI
340/360-2022 references ANSI/ASHRAE 37-2009 for several test
instructions, DOE has tentatively concluded that it is appropriate for
the existing incorporation by reference of ANSI/ASHRAE 37-2009 in
appendix A to apply to testing ECUACs and WCUACs. Given that the AHRI
1340-202X Draft references ANSI/ASHRAE 37-2009 for several test
instructions, DOE is proposing to additionally incorporate by reference
ANSI/ASHRAE 37-2009 for use with appendix A1.

D. Consideration of the ACUAC and ACUHP Working Group TP Term Sheet

In response to the May 2022 TP/ECS RFI, DOE received comments from
several stakeholders indicating support for the formation of an ASRAC
working group to convene and discuss representative test conditions for
CUACs and CUHPs. (AHRI, EERE-2022-BT-STD-0015-0008, at pp. 1-2; CA
IOUs, EERE-2022-BT-STD-0015-0012, at pp. 1-2; Lennox, EERE-2022-BT-STD-
0015-0009, at pp. 1-2; NEEA, EERE-2022-BT-STD-0015-0013, at pp. 6-7;
Trane, EERE-2022-BT-STD-0015-0014, at p. 2)
As a result, DOE published in the Federal Register the July 2022
Notice of Intent. 87 FR 45703 (July 29, 2022). DOE then established the
Working Group in accordance with FACA and NRA. The Working Group
consisted of 14 members and met six times, while the Working Group's
subcommittee met an additional seven times. The Working Group meetings
were held between September 20, 2022, and December 15, 2022, after
which the Working Group successfully reached consensus on an amended
test procedure. The Working Group signed a term sheet of
recommendations on December 15, 2022. (See EERE-2022-BT-STD-0015-0065)
The Working Group addressed the following aspects of the test procedure
for ACUACs and ACUHPs:
1. Mathematical representation of cooling efficiency: The current
cooling metric specified by AHRI 340/360-2022 (i.e., IEER) represents a
weighted average of the measured energy efficiency ratios (EER)
measured at four distinct test conditions, whereas the proposed IVEC
metric is calculated as the total annual cooling capacity divided by
the total annual energy use, as discussed further in section III.F.4 of
this document. The Working Group agreed that this calculation approach
provides a more mathematically accurate way of representing the cooling
efficiency of ACUACs and ACUHPs compared to the current approach used
for IEER. As part of this equation format,

[[Page 56403]]

the IVEC metric also uses hour-based weighting factors to represent the
time spent per year in each operating mode.
2. Integrated heating metric: The current heating metric for ACUHPs
(i.e., COP) represents the ratio of heating capacity to the power
input, calculated at a single test condition of 47 [deg]F. COP does not
account for the performance at part-load or over the range of
temperatures seen during an average heating season, and it does not
include energy use in heating season ventilation mode. IVHE accounts
for both full-load and part-load operation at a range of typical
ambient temperatures seen during the heating season, and it includes
energy use in heating season ventilation mode. Analogous to IVEC, the
proposed IVHE metric is calculated as the total annual heating load
divided by the total annual energy use, as discussed further in section
III.F.5 of this document, and the metric also uses hour-based weighting
factors to represent the time spent per year in each operating mode.
3. Operating modes other than mechanical cooling: The IEER metric
currently does not include the energy use of operating modes other than
mechanical cooling, such as economizer-only cooling and cooling season
ventilation. The newly established IVEC metric includes the energy use
of these other modes.
4. ESP: The IVEC and IVHE metrics require increased ESPs--in
comparison to the ESPs required for determining IEER and COP--to more
accurately represent ESPs and corresponding indoor fan power that would
be experienced in real-world installations.
5. Crankcase heater operation: The current IEER metric includes
crankcase heater power consumption only when operating at part-load
compressor stages (i.e., for part-load cooling operation, crankcase
heater power is included only for higher-stage compressors that are
staged off, and it is not included for lower-stage compressors when all
compressors are cycled off). The COP metric does not include any
crankcase heater power consumption. In contrast, the IVEC and IVHE
metrics include all annual crankcase heater operation, including when
all compressors are cycled off in part-load cooling or heating,
ventilation mode, unoccupied no-load hours, and in heating season (for
ACUACs only).
6. Oversizing: The current IEER and COP metrics do not consider
that ACUACs and ACUHPs are typically oversized in field installations.
In contrast, the proposed IVEC and IVHE metrics include an oversizing
factor of 15 percent (i.e., it is assumed that the unit's measured
full-load cooling capacity is 15 percent higher than the peak building
cooling load and peak building heating load). Accounting for oversizing
is more representative of the load fractions seen in field applications
and better enables the test procedure to differentiate efficiency
improvements from the use of modulating/staged components.
Based on discussions related to these six topics, the Working Group
developed the ACUAC and ACUHP Working Group TP Term Sheet, which
includes the following recommendations:
1. A recommendation to adopt the latest version of AHRI 340/360-
2022 with IEER and COP metrics required for compliance beginning 360
days from the date a test procedure final rule publishes (See
Recommendation #0);
2. The IVEC efficiency metric, to be required on the date of
amended energy conservation standards for ACUACs and ACUHPs (See
Recommendation #1);
3. Hour-based weighting factors for the IVEC metric (See
Recommendation #2);
4. Details on determination of IVEC, including provisions for
determining IVEC in appendix B of the ACUAC and ACUHP Working Group TP
Term Sheet (See Recommendation #3);
5. Target load fractions and temperature test conditions for IVEC,
which account for oversizing (See Recommendation #4);
6. A requirement that representations of full-load EER be made in
accordance with the full-load ``A'' test (See Recommendation #5); \16\
---------------------------------------------------------------------------

\16\ Similar to the current test procedure for determining IEER,
the test procedure recommended in the ACUAC and ACUHP Working Group
TP Term Sheet includes four cooling tests designated with letters
``A'', ``B'', ``C'', and ``D.'' The ``A'' test is a full-load
cooling test, while the ``B,'' ``C,'' and ``D'' tests are part-load
cooling tests.
---------------------------------------------------------------------------

7. A requirement to provide representations of airflow used for the
full load ``A'' test and the part load ``D'' test (i.e., the airflow
used in the lowest-stage test for the D point), and a provision for
determining the minimum airflow that can be used for testing (See
Recommendation #6);
8. The IVHE efficiency metric (See Recommendation #7);
9. Hour-based weighting factors, load bins, and outdoor air
temperatures for each bin (i.e., temperatures used for the building
heating load line, not test temperature conditions) for the IVHE metric
(See Recommendation #8);
10. The test conditions and list of required and optional tests and
representations for the IVHE metric (See Recommendation #9);
11. Provisions for manufacturers to certify cut-in and cut-out
temperatures for heat pumps to DOE and provisions for a DOE
verification test of those temperatures (See Recommendation #10);
12. Commitment of the Working Group to analyze ventilation and fan-
only operation included in the IVEC and IVHE metrics to validate that
these metrics adequately capture fan energy use during the energy
conservation standards portion of the negotiated rulemaking. If the
IVEC and IVHE levels do not adequately drive more efficient air moving
systems that are technologically feasible and economically justified,
the Working Group committed to developing a metric addressing furnace
fan energy use (See Recommendation #11);
13. ESP requirements for the IVEC and IVHE metrics, requirements
for splitting the ESP requirements between the return and supply ducts,
and a requirement that certified airflow for full load and D bin be
made public in the DOE Compliance Certification Database (See
Recommendation #12);
14. Provisions requiring manufacturers to certify crankcase heater
wattages and tolerances for certification (See Recommendation #13); and
15. Provisions that the contents of the ACUAC and ACUHP Working
Group TP Term Sheet be implemented in a test procedure NOPR and final
rule, with the final rule issuing no later than any energy conservation
standards direct final rule. (See Recommendation #14)

E. DOE Proposed Test Procedures

As discussed, EPCA requires that test procedures for covered
equipment, including CUACs and CUHPs, be reasonably designed to produce
test results that reflect energy efficiency, energy use, and estimated
operating costs of a type of industrial equipment (or class thereof)
during a representative average use cycle (as determined by the
Secretary), and shall not be unduly burdensome to conduct. (42 U.S.C.
6314(a)(2)) DOE has tentatively determined that the recommendations
specified in the ACUAC and ACUHP Working Group TP Term Sheet are
consistent with this EPCA requirement and is proposing amendments to
the existing test procedure in appendix A and a new test procedure in
appendix A1 in accordance with the Term Sheet.
In this NOPR, DOE is proposing to maintain the current efficiency
metrics of IEER, EER, and COP in appendix A, and is proposing to
reference AHRI 340/360-2022 in appendix A for measuring the existing
metrics. Thus, the proposed

[[Page 56404]]

amendments to appendix A would not affect the measured efficiency of
CUACs and CUHPs or require retesting solely as a result of DOE's
adoption of the proposed amendments to the appendix A test procedure,
if made final. Additionally, DOE is proposing to establish a new test
procedure at appendix A1 that would adopt the AHRI 1340-202X Draft,
including the newly proposed IVEC and IVHE metrics, ideally through
incorporation by reference of a finalized version of that industry test
standard. (If a finalized version of the AHRI 1340-202X Draft is not
published before the test procedure final rule, or if there are
substantive changes between the draft and published versions of the
standard that are not supported by stakeholder comments in response to
this NOPR, DOE may adopt the substance of the AHRI 1340-202X Draft or
provide additional opportunity for comment on the final version of that
industry consensus standard.) Use of appendix A1 would not be required
until the compliance date of any amended standards denominated in terms
of the new metrics in appendix A1, should such standards be adopted.
Specifically, in appendix A, DOE is proposing to adopt the
following sections of AHRI 340/360-2022: sections 3 (with certain
exclusions \17\), 4, 5, and 6, and appendices A, C, D (excluding
sections D1 through D3 \18\), and E.
---------------------------------------------------------------------------

\17\ DOE is not proposing to reference the following provisions
in section 3 of AHRI 340/360-2022 because the terms are either
defined at 10 CFR 431.92 or are not needed for the proposed DOE test
procedure: 3.2 (Basic Model), 3.4 (Commercial and Industrial Unitary
Air-conditioning Equipment), 3.5 (Commercial and Industrial Unitary
Heat Pump), 3.7 (Double-duct System), 3.8 (Energy Efficiency Ratio),
3.12 (Heating Coefficient of Performance), 3.14 (Integrated Energy
Efficiency Ratio), 3.23 (Published Rating), 3.26 (Single Package
Air-Conditioners), 3.27 (Single Package Heat Pumps), 3.29 (Split
System Air-conditioners), 3.30 (Split System Heat Pump), 3.36 (Year
Round Single Package Air-conditioners).
\18\ For reasons discussed in section III.I of this NOPR, DOE is
proposing provisions regarding configuration of unit under test at
10 CFR 429.43(a)(3)(v)(A), appendix A, and appendix A1 that are
distinct from the provisions in sections D1 through D3 of AHRI 340/
360-2022.
---------------------------------------------------------------------------

As previously mentioned in section I.B of this NOPR, DOE's test
procedure for ACUACs and ACUHPs currently specifies additional test
procedure requirements in sections 3 through 10 of the current appendix
A that are not included in ANSI/AHRI 340/360-2007 and that are related
to minimum ESP, optional break-in period, refrigerant charging, setting
indoor airflow, condenser head pressure controls, tolerance on capacity
at part-load test points, and condenser air inlet temperature for part-
load tests. Similarly, DOE's test procedure for ECUACs and WCUACs
currently specifies additional test procedure requirements in
paragraphs (c) and (e) of 10 CFR 431.96 regarding optional break-in
period and additional provisions for equipment setup. DOE has
tentatively determined that these DOE test procedure requirements that
are specified in appendix A and paragraphs (c) and (e) of 10 CFR 431.96
no longer need to be separately specified due to the addition of
equivalent provisions in AHRI 340/360-2022 and the AHRI 1340-202X
Draft. Therefore, DOE is proposing to remove these provisions from
appendix A and to revise Table 1 to 10 CFR 431.96 such that paragraphs
(c) and (e) are no longer listed as requirements for ECUACs and WCUACs,
instead utilizing the relevant provisions in AHRI 340/360-2022.
Further, in both appendix A and appendix A1, DOE is proposing to
incorporate by reference ANSI/ASHRAE 37-2009 and to utilize all
sections of that industry test method except sections 1 (Purpose), 2
(Scope), and 4 (Classifications).
Specifically for appendix A1, DOE is proposing to adopt sections of
AHRI 1340-202X Draft for measuring the IVEC and IVHE metrics, which are
generally consistent with the recommendations from the ACUAC and ACUHP
Working Group TP Term Sheet. In the proposed appendix A1, DOE is
proposing to adopt the following sections of the AHRI 1340-202X Draft:
sections 3 (with certain exclusions) 4, 5, and 6.1 through 6.3, and
appendices A, C, D (excluding D1 through D3), and E. Sections III.F.3,
III.F.4, III.F.5, and III.F.6 of this NOPR include further discussion
on the IVEC and IVHE metrics, as well as additions and revisions to the
IVEC and IVHE metrics that are included in the AHRI 1340-202X Draft but
not in the ACUAC and ACUHP Working Group TP Term Sheet. Sections
III.F.7 and III.F.6.d of this NOPR include further discussion on the
IVEC and IVHE metrics specified in the AHRI 1340-202X Draft that DOE is
proposing to adopt in appendix A1 for ECUACs, WCUACs, and double-duct
systems.
The ACUAC and ACUHP Working Group TP Term Sheet applies only to the
test procedures for ACUACs and ACUHPs excluding double-duct systems.
However, AHRI 1340-202X Draft includes additional provisions for
determining IVEC and IVHE for double-duct systems, ECUACs, and WCUACs--
indicating industry consensus that these metrics are appropriate for
these categories of CUACs and CUHPs. DOE has tentatively determined
that the test procedures for CUACs and CUHPs as proposed would improve
the representativeness of the current Federal test procedure for CUACs
and CUHPs and would not be unduly burdensome to conduct. Specifically,
DOE has tentatively concluded that testing CUACs and CUHPs (including
double-duct systems, ECUACs, and WCUACs) in accordance with the test
provisions in the most recent draft of the applicable consensus
industry test procedure AHRI 1340-202X Draft (which incorporates
recommendations of the ACUAC and ACUHP Working Group TP Term Sheet,
including adopting the new IVEC and IVHE metrics) would provide more
representative results and more fully comply with the requirements of
42 U.S.C. 6314(a)(2) than testing strictly in accordance with AHRI 340/
360-2022. Therefore, DOE is proposing to amend the test procedure for
CUACs and CUHPs to adopt in the proposed new appendix A1 the test
provisions in AHRI 1340-202X Draft and ASHRAE 37-2009.
Issue 2: DOE requests feedback on its proposal to adopt the IVEC
and IVHE metrics as determined under AHRI 1340-202X Draft in appendix
A1 of the Federal test procedure for ACUACs and ACUHPs (including
double-duct systems), ECUACs, and WCUACs.

F. Efficiency Metrics and Test Conditions

In response to the July 2017 TP RFI, May 2020 ECS RFI, and May 2022
TP/ECS RFI, DOE received comment on a number of topics related to
changing the metrics and/or test conditions used for determining CUAC
and CUHP efficiency. The following sections: (1) summarize comments
received on these topics; (2) discuss the current test conditions and
metrics in appendix A; (3) discuss the test conditions and metrics
proposed to be included in appendix A1; (4) discuss the newly proposed
IVEC metric; (5) discuss the newly proposed IVHE metric; (6) discuss
additions and revisions to the IVEC and IVHE metrics that are included
in the AHRI 1340-202X Draft but not the ACUAC and ACUHP Working Group
TP Term Sheet; and (7) discuss metrics specific to double-duct systems.
1. Comments Received on Metrics
In response to the July 2017 TP RFI, May 2020 ECS RFI, and May 2022
TP/ECS RFI, DOE received comments regarding a number of test procedure
topics. In the following subsections, DOE briefly summarizes these
topics,

[[Page 56405]]

including the corresponding comments received and DOE's responses.
DOE notes that many of the issues raised by commenters had not yet
been addressed through an industry consensus test procedure at the time
the comments were submitted to DOE. Many of these issues were raised
subsequently during the Working Group, and the newly proposed IVEC and
IVHE metrics would largely address the major concerns previously
expressed by commenters.
a. IEER Test Conditions and Weighting Factors
In the July 2017 TP RFI, DOE welcomed comment on any aspect of the
existing test procedures for CUACs and CUHPs not specifically addressed
by the RFI, particularly with regard to information that would improve
the representativeness of the test procedures. 82 FR 34427, 34448.
(July 25, 2017).
With respect to the IEER test conditions and weighting factors, the
CA IOUs suggested raising the highest ambient dry-bulb temperature test
point used for determining IEER, stating that the 95 [deg]F condition
specified in the test procedure does not reflect the conditions
experienced in the western climate and on many rooftops throughout the
country. (CA IOUs, EERE-2017-BT-TP-0018-0007 at p. 3)
Additionally, in response to the May 2020 ECS RFI, DOE received
comments and test data from Verified recommending changes to the IEER
weighting factors and indoor and outdoor air temperature test
conditions in AHRI 340/360, particularly to account for the use of
economizers (discussed further in section III.F.1.d) and changes in
climate due to global climate change. (Verified, EERE-2019-BT-STD-0042-
0011 at pp. 3-7) DOE also received comments from two individuals
supporting the statements made by Verified. (Heinemeier, EERE-2019-BT-
STD-0042-0012 at p. 1; Walsh, EERE-2019-BT-STD-0042-0018 at p. 1)
In response to the May 2022 TP/ECS RFI, DOE received several
comments regarding the weighting factors used in the IEER metric,
specifically relating to the building types considered in the current
test procedure. ASAP and ACEEE asserted that the current IEER weighting
factors should be adjusted to account for additional building types
that were not considered when initially developing IEER. (ASAP and
ACEEE, EERE-2022-BT-STD-0015-0011, at p. 2)
Carrier noted that IEER was developed using three building types
(specifically, office, retail, and school buildings) and asserted that
for an updated analysis, the 16 building types currently in ASHRAE 90.1
should be considered where applicable to ACUACs and ACUHPs. (Carrier,
EERE-2022-BT-STD-0015-0010, at pp. 14-15) Carrier also noted that it
had developed a model that outputs load profiles for the 16 ASHRAE 90.1
building types for each of the 19 global climate zones in ASHRAE 169-
2013 and was using its model to evaluate the effects of ventilation,
ASHRAE 90.1 requirements for economizer free cooling and energy
recovery, updated heating metrics, different climate zones and building
load profiles, and updated ESPs. (Carrier, EERE-2022-BT-STD-0015-0010,
at pp. 1-6)
Additionally, Carrier noted that the weighting factors developed
during the 2005 process to create IEER were based on ton-hours and not
purely on hours, noting that high-capacity hours have more weight than
the lower capacity hours in terms of energy use. (Carrier, EERE-2022-
BT-STD-0015-0010, at pp. 12-13). Carrier also explained that the
weighting for the A test condition was based on the 97-percent to 100-
percent capacity range because it would not have been appropriate to
use a larger bin with the rating condition at the extreme upper limit
of the bin. Id. Carrier recommended that if DOE were to update the
cooling metric, DOE should consider the following: (1) oversizing, (2)
re-evaluating test points and weighting factors if ventilation and
economizing are included, (3) test uncertainty at very low loads, and
(4) varying return air temperatures. Id.
AHRI stated that energy use during cooling varies based on climate
zone, building type, construction, and use, and that ASHRAE SSPC 90.1
has developed reference cities for all 19 climate zones and defined 16
reference buildings that represent 83 percent of the market. (AHRI,
EERE-2022-BT-STD-0015-0008, at p. 5)
As presented in the September 20-21, 2022, Working Group meetings,
the Working Group evaluated the weighting factors and test conditions
specified in conjunction with the newly proposed IVEC metric using the
models developed by Carrier, which include several ASHRAE 90.1 building
types and climate zones for which ACUACs and ACUHPs are installed. (See
EERE-2022-BT-STD-0015-0019, pp. 9-22) The weighting factors and their
development are further discussed in section III.F.4 of this NOPR. DOE
believes that these provisions address the issues raised by commenters
as summarized previously in this section, and proposes to adopt in
appendix A1 the adjusted IVEC weighting factors that are specified in
AHRI 1340-202X Draft and discussed in section III.F.6.a of this NOPR.
b. Energy Efficiency Metrics for ECUACs and WCUACs
For ECUACs and WCUACs of all regulated cooling capacities, DOE
currently prescribes standards in terms of the EER metric for cooling-
mode operation. 10 CFR 431.97(b); see Table 1 to 10 CFR 431.97. This
differs from ACUACs and ACUHPs with cooling capacities greater than or
equal to 65,000 Btu/h (excluding double-duct systems), for which DOE
currently prescribes energy conservation standards in terms of the IEER
metric for cooling-mode operation and in terms of COP for heating-mode
operation. 10 CFR 431.97(b); see Table 3 and Table 4 to 10 CFR 431.97.
Unlike EER, which represents the efficiency of the equipment operating
only at full load, IEER represents the efficiency of operating at part-
load conditions of 75 percent, 50 percent, and 25 percent of capacity
in addition to the efficiency at full load. The IEER metric provides a
more representative measure of energy consumption in actual operation
of CUACs and CUHPs by weighting the full-load and part-load
efficiencies with the average amount of time the equipment spends
operating at each load point. AHRI 340/360-2022 includes both the EER
and IEER metrics for ECUACs and WCUACs. ASHRAE 90.1-2019 and ASHRAE
90.1-2022 specify minimum efficiency levels for ECUACs and WCUACs in
terms of both EER and IEER.
As discussed in the July 2017 RFI, ANSI/AHRI 340/360-2007 includes
a method for testing and calculating IEER for ECUACs and WCUACs. DOE
requested comment and data on whether the IEER part-load conditions and
IEER weighting factors are representative of the operation of field-
installed ECUACs and WCUACs, and on the typical cycling losses of
field-installed ECUACs and WCUACs. 82 FR 34427, 34440 (July 25, 2017).
On this topic, AHRI, Carrier, and Goodman commented that the
weighting factors are based on building load profiles and should not
depend on equipment category. (AHRI, EERE-2017-BT-TP-0018-0011 at p.
22; Carrier, EERE-2017-BT-TP-0018-0006 at p. 8; Goodman, EERE-2017-BT-
TP-0018-0014 at p. 3) ASAP, ASE, et al. encouraged DOE to adopt IEER as
the efficiency metric for ECUACs and WCUACs, stating that ECUACs and
WCUACs spend most of their operating

[[Page 56406]]

time in part load, and that using IEER for these equipment types would
provide consistency in ratings with ACUACs and ACUHPs and better
represent performance in the field. (ASAP, ASE, et al., EERE-2017-BT-
TP-0018-0009 at pp. 4-5) In contrast, Goodman stated that the WCUAC
market is so small that there would be no value in changing the
regulated metric to IEER for such equipment. (Goodman, EERE-2017-BT-TP-
0018-0014 at p. 3)
DOE responds to these commenters as follows. In the proposed
appendix A, for ECUACs and WCUACs, DOE proposes to include both the
required EER metric and the optional IEER metric, as well as the test
procedure specified in AHRI 340/360-2022, in the DOE test procedure so
as to allow for required representations using the EER metric and
optional representations using the IEER metric. In a final
determination published in the Federal Register on July 14, 2021, DOE
discussed the potential for amended energy conservation standards for
ECUACs and WCUACs denominated in terms of IEER, but the Department
concluded that such a metric change was not warranted and ultimately
maintained the current standards denominated in terms of EER. 86 FR
37001, 37004-37005. As part of this rulemaking, DOE is proposing the
IEER provisions as an optional test procedure to allow for consistent
and comparable representations in terms of IEER when testing to
appendix A, should a manufacturer choose to make such representations.
As discussed, DOE is proposing to adopt the IVEC metric for ECUACs
and WCUACs in the proposed appendix A1, as determined in the AHRI 1340-
202X Draft. DOE has tentatively concluded that the inclusion of the
IVEC metric for ECUACs and WCUACs in AHRI 1340-202X Draft represents
industry consensus that the metric provides a representative measure of
efficiency for ECUACs and WCUACs. Section III.F.6.d of this NOPR
includes further discussion of the IVEC metric for ECUACs and WCUACs.
c. Cyclic Degradation Factor for Cooling
In section 6.2.3.2 of AHRI 340/360-2022, units that are unable to
reduce their capacity to meet one of the IEER part load rating points
(i.e., 75 percent, 50 percent, or 25 percent) are tested under steady-
state conditions at the minimum stage of compression that the unit is
able to achieve. In real-world installations, these same units would
typically operate under non-steady-state conditions because the
compressor would cycle to reduce the unit's capacity to meet the
desired cooling load. AHRI 340/360-2022 require units unable to reduce
their capacity below one of the part load rating points have the EER
for that rating point calculated using a cyclic degradation
coefficient. This degradation coefficient, which is calculated based on
the load fraction and ranges from 1 to 1.13, is included in the
denominator of the EER calculation for that rating point and is
multiplied by the sum of the compressor and condenser fan power in
order to simulate the efficiency degradation of compressor and
condenser fan cycling.
With respect to cyclic degradation, DOE received a comment in
response to the July 2017 TP RFI from the CA IOUs recommending that DOE
investigate the cyclic degradation factor in AHRI 340/360-2015 to
verify that the degradation coefficient will never exceed 1.13. (CA
IOUs, EERE-2017-BT-TP-0018-0007 at p. 2)
DOE also received a comment in response to the May 2020 ECS RFI
from Verified questioning the validity of the cyclic degradation factor
in AHRI 340/360-2019, stating that its laboratory tests found that
relative cycling losses of a 7.5-ton system were more than double the
losses for a 3-ton system. (Verified, EERE-2019-BT-STD-0042-0011 at p.
10)
While the Working Group discussed calculation methods for IVEC
during the ACUAC and ACUHP Working Group meetings, the Working Group
did not discuss any alternatives to the cyclic degradation approach
specified in AHRI 340/360-2022. Additionally, the ACUAC and ACUHP
Working Group TP Term Sheet includes the cyclic degradation calculation
method specified in AHRI 340/360-2022 as part of the IVEC metric
calculation method. At this time, DOE lacks clear and convincing
evidence to deviate from the cyclic degradation approach in AHRI 340/
360-2022 that is recommended in the ACUAC and ACUHP Working Group TP
Term Sheet and included in AHRI 1340-202X Draft. Therefore, DOE is not
proposing to adopt a cyclic degradation approach that differs from the
approach specified in these documents.
d. Economizing and Ventilation
In 2015, DOE initiated a rulemaking effort for the ASRAC Commercial
and Industrial Fans and Blowers Working Group (CIFB Working Group) to
negotiate the scope, test procedure, and standards for commercial and
industrial fans and blowers. 80 FR 17359. The CIFB Working Group issued
a term sheet with recommendations regarding the energy conservation
standards, test procedures, and efficiency metrics for commercial and
industrial fans and blowers (CIFB Term Sheet). (See Document No. 179 in
Docket No. EERE-2013-BT-STD-0006.) Recommendation #3 of the CIFB Term
Sheet identifies a need for DOE's test procedures and related
efficiency metrics for CUACs and CUHPs to more fully account for the
energy consumption of fans embedded in regulated commercial air-
conditioning equipment. (Id. at pp. 3-4) In addition, the CIFB Working
Group recommended that in the next round of test procedure rulemakings,
DOE should consider revising efficiency metrics that include energy use
of supply and condenser fans to include the energy consumption during
all relevant operating modes (e.g., auxiliary heating mode, ventilation
mode, and part-load operation). (Id.)
The Commercial Package Air Conditioners Working Group also
developed recommendations regarding fan energy use in a term sheet.
(See Document No. 93 in Docket No. EERE-2013-BT-STD-0007) The
Commercial Package Air Conditioners Working Group recommended that DOE
initiate a rulemaking with a primary focus of better representing total
fan energy use in real-world installations, including consideration of
fan operation for operating modes other than mechanical cooling and
heating.\19\ (Id. at p. 2)
---------------------------------------------------------------------------

\19\ Mechanical cooling and heating refer to a ACUAC and ACUHP
using the refrigeration cycle to cool and heat the indoor space, and
does not refer to other forms of unit operation (e.g., economizing,
ventilation, or supplemental heating).
---------------------------------------------------------------------------

As part of the July 2017 TP RFI, DOE requested comment and data on
the operation of CUAC and CUHP supply fans when there is no demand for
heating and cooling, as well as the impact of ancillary functions
(e.g., primary heating, auxiliary heating, and economizers \20\) on the
use and operation of the supply fan. 82 FR 34427, 34440.
---------------------------------------------------------------------------

\20\ An economizer is a system that enables an ACUAC or ACUHP to
supply outdoor air instead of return air from the conditioned space
in order to reduce or eliminate mechanical cooling operation in mild
or cold weather conditions. In economizer-only cooling, the indoor
fan runs to supply outdoor air to meet cooling load, but there is no
mechanical cooling operation--i.e., compressor(s) and condenser fans
do not operate.
---------------------------------------------------------------------------

In response to the July 2017 TP RFI, Carrier and AHRI commented
that fan operation in ventilation hours cannot properly be accounted
for without including economizer operation in testing. (Carrier, EERE-
2017-BT-TP-0018-0006 at p. 9; AHRI, EERE-2017-BT-TP-0018-0011 at p. 23)
AHRI and Goodman commented that manufacturers and third-party
laboratories do not currently have test

[[Page 56407]]

facilities that can accommodate testing of ACUACs and ACUHPs with
economizers operating because such testing requires air to be pulled
from the outdoor room into the indoor room. (AHRI, EERE-2017-BT-TP-
0018-0011 at p. 22; Goodman, EERE-2017-BT-TP-0018-0014 at p. 3) AHRI
further stated that because of the lack of test facilities to
accommodate this type of testing, incorporation of ventilation into an
efficiency metric is still not practical. (AHRI, EERE-2017-BT-TP-0018-
0011 at p. 23)
In the May 2022 TP/ECS RFI, DOE acknowledged a need to further
investigate the prevalence and operating hours of economizers and
ventilation. DOE requested comment and data on several issues including
the number of units installed with economizers per climate zone, the
operating hours of economizers by climate zone, and the methodology
used to determine operating hours in each cooling mode, especially
those that might contribute to the creation of a new metric.
In response to the May 2022 TP/ECS RFI, the CA IOUs, NYSERDA, and
ASAP and ACEEE commented that the current test procedure does not
account for the fan energy use outside of mechanical cooling and
heating modes. (CA IOUs, EERE-2022-BT-STD-0015-0012, at p. 2; ASAP and
ACEEE, EERE-2022-BT-STD-0015-0011, at pp. 1-2, NYSERDA, EERE-2022-BT-
STD-0015-0007, at p. 3)
Specifically, the CA IOUs recommended that DOE consider the
California 2022 Title 24 codes and standards enhancement effort for
potential solutions. (CA IOUs, EERE-2022-BT-STD-0015-0012, at p. 2)
NYSERDA recommended that DOE consider factoring in fan energy using
temperature rise provisions, further detailed in comments submitted by
NYSERDA in response to the commercial warm air furnace test procedure
NOPR published February 5, 2022 (see 87 FR 10726). (NYSERDA, EERE-2022-
BT-STD-0015-0007, at p. 3)
Regarding the distribution of installed economizers, AHRI stated
that although many economizers are field-installed, AHRI is considering
collecting data on factory-installed economizers, particularly by state
or climate zone. (AHRI, EERE-2022-BT-STD-0015-0008, at p. 5) AHRI did
not provide any such data in its comment.
ASAP and ACEEE cited AHRI data indicating that economizers are
typically installed in CUACs. ASAP and ACEEE noted that ASHRAE 90.1-
2019 requires economizers in all but one climate zone, suggesting the
importance of incorporating fan energy use during economizer only
cooling mode. (ASAP and ACEEE, EERE-2022-BT-STD-0015-0011, at pp. 1-2)
Lennox commented that its information indicates that the percentage
of CUACs and CUHPs shipped with factory installed economizers ranges
from around 30 percent to 80 percent by state, averaging around 55
percent in the U.S. (Lennox, EERE-2022-BT-STD-0015-0009, at p. 5)
Lennox noted that the total percentage is likely far higher than this
level when field-installed economizers are taken into account. Id.
Lennox also stated that its information indicates that a higher
fraction of equipment in northern climates contain economizers than in
warmer southern climates. Lennox recommended that DOE review the
standard and code requirements for where economizers are required in
order to assess the fraction of products installed with economizers in
each climate zone. Id.
Carrier commented that, based on the market distribution data used
for the ASHRAE 90.1 determination, economizers are required on
approximately 96 percent of the 16 reference buildings' weighted sales.
(Carrier, EERE-2022-BT-STD-0015-0010, at pp. 9-10)
Regarding economizer hours and methodology for determination of
hours in each bin load, AHRI stated that DOE should use the heating and
cooling load modeling used to develop IEER to understand the heating,
cooling, and economizing hours for CUACs and CUHPs. (AHRI, EERE-2022-
BT-STD-0015-0008, at p. 3)
Carrier provided data showing the hours CUACs and CUHPs spend in
economizer only, integrated economizer, and mechanical only cooling
developed as part of ASHRAE 90.1 economizer studies it has conducted.
(Carrier, EERE-2022-BT-STD-0015-0010, at p. 12) Carrier stated that the
2005 analysis performed to determine the IEER metric was based on the
mechanical cooling operation, including hours where integrated
economizers are used, but that it did not account for the benefits of
the economizer capacity. (Carrier, EERE-2022-BT-STD-0015-0010, at pp.
12-13)
In addition to distribution and operating information, DOE received
multiple recommendations in response to the May 2022 TP/ECS RFI
relating to the inclusion of economizer or ventilation data in a new
efficiency metric.
The CA IOUs stated that economizer performance is highly dependent
on the use of climate-zone appropriate controls, and that economizers
are often shipped with conservative default control settings
appropriate for warm and moist areas. (CA IOUs, EERE-2022-BT-STD-0015-
0012, at pp. 3-4) The CA IOUs asserted that including economizers in
the CUAC and CUHP energy efficiency metric would not be beneficial
because it would preempt climate-zone-dependent economizer requirements
in building codes. Id. The CA IOUs explained that economizers and their
installed controls are often sold by third parties, and that original
equipment manufacturers (OEMs) usually do not determine the method of
economizer control or quality of construction. Id. The CA IOUs stated
that DOE may need to determine if independently manufactured
economizers fall within its statutory authority and if it is feasible
to regulate them. Id. Furthermore, the CA IOUs asserted that designing
a test procedure that measures a significant difference between models
may be challenging unless the test includes operation as an integrated
economizer, in which case the difference in performance would be driven
by the unit's capacity control and turndown capability. Id.
Carrier asserted that the downside of including the ventilation
cooling hours in a new cooling metric is that it would decrease the
focus on the mechanical cooling, and that evaluation of mechanical
cooling performance was the intent of the current IEER metric.
(Carrier, EERE-2022-BT-STD-0015-0010, at pp. 9-10) Carrier requested
that if the IEER metric and test procedure are modified to include
ventilation fan power, the benefits of the economizer and also energy
recovery be included to account for the actual capabilities of such a
large application base. Id.
Based on comments received in response to the July 2017 TP RFI and
the May 2020 ECS RFI, DOE recognized in the May 2022 TP/ECS RFI a need
to further investigate fan operation during ventilation or air
circulation/filtration and economizing. Specifically, while comments
received previously had indicated the prevalence of multi-speed fans
that reduce fan speed in these operating modes, the commenters had not
indicated how the fan speed in these operating modes typically compares
to fan speed when operating at the lowest stage of compressor cooling.
Thus, in the May 2022 TP/ECS RFI, DOE sought feedback on the supply
airflow and fan power at the lowest stage of compression for variable
air volume and staged air volume fans in relation to ventilation, air
circulation, and

[[Page 56408]]

economizer-only cooling. 87 FR 31743, 31750-31751.
In response to the May 2022 TP/ECS RFI, AHRI and Lennox recommended
that DOE review ASHRAE 62.1 ``Ventilation for Acceptable Indoor Air
Quality,'' which specifies minimum ventilation rates and other measures
to achieve proper indoor air quality control in commercial buildings.
(AHRI, EERE-2022-BT-STD-0015-0008, at pp. 4-5; Lennox, EERE-2022-BT-
STD-0015-0009, at pp. 4-5) AHRI noted that ventilation rates specified
by ASHRAE 62.1 vary from 18 percent to 60 percent based on building
type. (AHRI, EERE-2022-BT-STD-0015-0008, at p. 4) AHRI also noted that
ASHRAE 90.1-2019 provides minimum requirements for the CUACs and CUHPs,
including the requirement to have two-speed fans. Id. AHRI stated that
airflow, including during ventilation, will be different for CUACs and
CUHPs if the product is multi-zone variable air volume (MZVAV), single-
zone variable air volume (SZVAV), or constant volume, and that the
relationship between fan power, airflow, and code requirements must be
considered when developing a metric change that incorporates
ventilation. (AHRI, EERE-2022-BT-STD-0015-0008, at pp. 4-5) AHRI also
stated that ventilation occurs only during occupied mode. (AHRI, EERE-
2022-BT-STD-0015-0008, at p. 5)
Lennox stated that CUAC and CUHP systems are generally designed to
meet minimum ventilation requirements in all operating modes. (Lennox,
EERE-2022-BT-STD-0015-0009, at p. 5) Lennox recommended that for the
test procedure, the airflow in ventilation-only mode be set at the same
as the airflow used at the minimum stage of capacity. Id. Lennox stated
that for economizer-only cooling, the systems are generally designed to
meet a supply air temperature setpoint, and that the supply airflow
volume is influenced by outside air temperature and/or the cooling
demand of the conditioned space to attain this setpoint. Id. Lennox
stated that the economizer-only supply airflow might not be the same as
the lowest stage of compression and can be less than the airflow at the
lowest stage of compression. Id.
Carrier stated that for ventilation-only operation, the airflow may
or may not be the same as the minimum stage of capacity, and that the
airflow depends on the controls and application, as well as the
required ventilation rate. (Carrier, EERE-2022-BT-STD-0015-0010, at p.
9) Carrier also stated that fan speeds can be higher during economizer
cooling operation. Id. Carrier noted that ASHRAE 90.1 requires
economizers to be capable of 100-percent airflow and that the maximum
economizer capacity be used before turning on the mechanical cooling of
the integrated economizer option. Id.
NEEA noted that CUAC and CUHP standard rating conditions do not
consider operating modes where ventilation air (either mixed or not
mixed with return air) is actively heated or cooled. NEEA stated that
it recognizes that the impact of certain features--including
economizers and ventilation systems--will vary depending on the amount
of ventilation air introduced by the CUAC/CUHP. NEEA described, for
example, that in 30-percent and 100-percent outside air systems, energy
recovery represents a significant opportunity for energy savings,
whereas in 0-percent outside systems, enclosure improvements or
reducing damper leakage may present the greatest opportunity for energy
savings. NEEA asserted that by only accounting for 0-percent outside
air cooling and heating modes, the current efficiency metrics give
misleading signals to manufacturers and consumers about what models
will decrease energy consumption. NEEA recommended that DOE consider
how the market categorizes CUAC and CUHP equipment and ensure that DOE
product definitions align with the market and not just what is simplest
for regulation. (NEEA, EERE-2022-BT-STD-0015-0013 at p. 6)
During negotiations for the Working Group, the Working Group agreed
not to include testing with economizers operating due to test burden
and repeatability concerns. (See EERE-2022-BT-STD-0015-0048 at pp. 55-
57) However, the Working Group agreed to include operating hours and
fan energy use associated with economizer operation (reflecting both
factory-installed and field-installed economizers). (See EERE-2022-BT-
STD-0015-0053 at pp. 9, 32) DOE and other participating stakeholders
then assessed market data of economizer distribution. Due to the wide
distribution of economizers identified through this analysis, all
caucuses agreed to include the economizer benefit and energy use in the
new integrated cooling metric--IVEC. To ensure representative
consideration of economizers in the cooling metric, the calculation for
the IVEC metric incorporates both the cooling benefit and energy use
associated with the hours of cooling contribution provided in
integrated economizing and economizer-only cooling modes. The IVEC
metric also includes the energy use associated with cooling season
ventilation operation. To determine the breakdown of hours among
economizer-only cooling, integrated economizer, mechanical cooling-
only, and cooling season ventilation operation for the IVEC metric, the
Working Group utilized the previously discussed building modeling of
several ASHRAE 90.1 building types and climate zones in which CUACs and
CUHPs are installed. DOE has tentatively determined that the proposed
inclusion of fan energy for economizing and ventilation operating modes
in the IVEC cooling metric--in conjunction with other proposed test
condition changes--addresses the concerns previously raised regarding
fan energy representation in the efficiency metric, and proposes to
adopt the IVEC metric as specified in the AHRI 1340-202X Draft.
e. External Static Pressure Requirements
In the testing of air conditioners and heat pumps, ESP requirements
simulate the resistance that the indoor fan must overcome from the air
distribution system when installed in real-world installations. Both
AHRI 210/240 (i.e., the 2008, 2017, and 2023 versions) and AHRI 340/360
(i.e., the 2007, 2015, 2019, and 2022 versions) specify minimum ESPs
for testing based on the unit's rated capacity. Minimum ESPs are
specified in Table 7 of AHRI 340/360-2022 and range from 0.10-0.20
inches of water column (in. H<INF>2</INF>O) for ACUACs and ACUHPs with
a rated cooling capacity less than 65,000 Btu/h, and range from 0.2-
0.75 in. H<INF>2</INF>O for all CUACs with cooling capacity greater
than or equal to 65,000 Btu/h. These values align with the ESP
requirements specified in the current DOE test procedure.
In 2015, the Commercial Package Air Conditioners Working Group
recommended that the energy use analysis conducted for the January 2016
Direct Final Rule should use higher ESPs than those specified in the
DOE test procedure to help better simulate real-world applications. 81
FR 2420, 2470 (Jan. 15, 2016). Specifically, the Commercial Package Air
Conditioners Working Group recommended ESPs of 0.75 and 1.25 in.
H<INF>2</INF>O, which corresponded to the ESPs used in modified
building simulations of the cooling load. Id. The ESP values
recommended by the Commercial Package Air Conditioners Working Group
did not vary with capacity. Recommendation #2 of the term sheet
developed by the Commercial Package Air Conditioners Working Group
suggested that DOE should amend the test procedure for CUACs and CUHPs
to better represent the total fan energy use

[[Page 56409]]

by considering alternative ESPs. (See Document No. 93 in Docket No.
EERE-2013-BT-STD-0007 at p. 2) Higher ESPs at the same airflow would
result in higher fan power measured during testing and would,
therefore, result in fan energy use comprising a larger fraction of
total energy use measured during the test.
In the May 2022 TP/ECS RFI, DOE sought data and comment on
representative ESPs in the field of all CUACs and CUHPs. 87 FR 31743,
31749 (May 25, 2022). NEEA provided a comment, recommending generally
that DOE establish a more representative ESP value for testing all
CUACs and CUHPs based on the previous recommendation from the
Commercial Package Air Conditioners Working Group. (NEEA, EERE-2022-BT-
STD-0015-0013 at pp. 7-8) NEEA noted that the ESP levels used by DOE
for the energy use analysis during the last energy conservation
standards rulemaking for ACUACs and ACUHPs are two to three times
higher than the required ESPs in the existing test procedure. Id. NEEA
stated that these values were more representative of units in the field
due to the ESP used in this test procedure not including the return
ductwork pressure loss, which NEEA described as significant because
many units do not include return fans. Id.
The CA IOUs supported updates to the CUAC and CUHP test procedure
to improve the representation of fan energy use, particularly by
updating the required ESPs in the test procedure. (CA IOUs, EERE-2022-
BT-STD-0015-0012 at p. 2) Specifically regarding ESPs, the CA IOUs
encouraged DOE to explore California's 2022 Title 24 codes and
standards-enhancement effort for air distribution enhancements. Id. The
CA IOUs, as well as NYSERDA and ASAP and ACEE, recommended that DOE
consider alternative ESP values more representative of units in real-
world installations. (CA IOUs, EERE-2022-BT-STD-0015-0012, at p. 2;
ASAP and ACEEE, EERE-2022-BT-STD-0015-0011, at pp. 1-2; NYSERDA, EERE-
2022-BT-STD-0015-0007, at p. 3)
AHRI and Lennox stated that CUACs and CUHPs are designed to cover a
range of ESPs, noting that big box retail stores could have an ESP of
0.5 in. H<INF>2</INF>O and that multi-story offices could exceed ESPs
of 2.0 in. H<INF>2</INF>O. (AHRI, EERE-2022-BT-STD-0015-0008 at pp. 2-
3; Lennox, EERE-2022-BT-STD-0015-0009 at p. 2) AHRI noted that the
Commercial Package Air Conditioners Working Group agreed to use 0.75
and 1.25 in. H<INF>2</INF>O for the energy conservation standards
energy use analysis. Id. AHRI stated that its members were unable to
form a consensus position on the issue of representative ESPs for CUACs
and CUHPs before the comment period ended; however, AHRI may submit
supplementary comments to DOE or a working group if one were to be
formed. (AHRI, EERE-2022-BT-STD-0015-0008 at p. 3)
Lennox stated that while its review of data was ongoing regarding a
representative ESP recommendation, it found the ESP levels used by the
Commercial Package Air Conditioners Working Group to be reasonable.
Lennox recommended that the ESPs used for testing increase according to
the capacity breaks specified in AHRI 340/360 because ESPs generally
increase with product capacity. (Lennox, EERE-2022-BT-STD-0015-0009 at
pp. 2-3) Lennox also commented the applied static pressure from ECUACs
and WCUACs did not vary from similar air source products and
recommended similar values be used for product performance comparison.
(Id. at p. 3)
Carrier stated that it agreed some adjustments to the ESPs might be
appropriate, but that several things need to be reviewed before the
ESPs are revised. Carrier also stated that ESPs can vary significantly
depending on the application. Specifically, Carrier stated that some
applications can use concentric ductwork, where ESPs are likely higher
than the current ESPs in AHRI 340/360-2022; and other applications use
variable air volume (VAV) systems, which have more extensive ductwork
and added pressure drop from terminals. Carrier stated that for larger
equipment, the applications are more complex because the equipment is
larger and ductwork design can vary based on the building design.
Carrier mentioned a general trend that static pressure and ductwork
length increase with equipment size, but also mentioned that this
depends on the building design, configuration, and system type. Carrier
stated that it is in the process of reviewing job design data and
applications and will have that data for further discussions once it is
received. Additionally, Carrier stated that performing an analysis of
the ASHRAE Standard 90.1 fan power budget addendum BO may also provide
additional insight to proper static pressure levels. (Carrier, EERE-
2022-BT-STD-0015-0010 at p. 7)
In the May 2022 RFI, DOE also sought specific data on ESPs for
ECUACs and WCUACs with cooling capacities less than 65,000 Btu/h, as
well as feedback on whether a representative ESP value for testing
would be 0.5 in H<INF>2</INF>O (as referenced for air-cooled CUACs
<65,000 Btu/h in AHRI 210/240-2023), the range of 0.10 to 0.20 in
H<INF>2</INF>O (from AHRI 340/360-2022), or alternative values. For
WCUACs with a cooling capacity of less than 65,000 Btu/h, DOE's
preliminary analysis showed that these units may typically be installed
above dropped ceilings in commercial buildings. For ECUACs with a
cooling capacity of less than 65,000 Btu/h, DOE's preliminary analysis
shows that these units are primarily marketed for residential
applications, which suggests that it may be appropriate to align the
ESP requirements for ECUACs with a cooling capacity of less than 65,000
Btu/ h with those specified for CAC/HPs in 10 CFR part 430, subpart B,
appendix M1 (appendix M1) (i.e., 0.5 in H<INF>2</INF>O for conventional
units). Therefore, DOE considered whether it was appropriate for the
same ESP requirements to be applied for both ECUACs and WCUACs with a
cooling capacity of less than 65,000 Btu/h. 87 FR 31743, 31750 (May 25,
2022).
Carrier stated that the ESPs for ECUACs and WCUACs less than 65,000
Btu/h in the field would not be much different than the average values
used for the AHRI 210/240-2023 analysis.\21\ Carrier asserted that ESP
values in the field might be lower than those ESPs, because some ECUACs
and WCUACs with a capacity less than 65,000 Btu/h are applied with
short supply ducts and no return ducts or can also be used with
concentric ducts. (Carrier, EERE-2022-BT-STD-0015-0010 at pp. 7-8)
Lennox recommended the ESP value of 0.5 in H<INF>2</INF>O from AHRI
210/240-2023 be used for ECUACs and WCUACs with cooling capacity less
than 65,000 Btu/h. (Lennox, EERE-2022-BT-STD-0015-0009 at p. 3)
---------------------------------------------------------------------------

\21\ In its comment, Carrier mentioned the ``AHRI 210/240-2003
analysis.'' Because there is no 2003 version of AHRI 210/240 and the
ESP requirements for air-cooled central air conditioners and heat
pumps with cooling capacity less than 65,000 Btu/h were updated in
AHRI 210/240-2023, DOE interprets the intent of Carrier's comment as
referring to AHRI 210/240-2023.
---------------------------------------------------------------------------

The majority of comments received in response to both the July 2017
TP RFI and May 2022 TP/ECS RFI indicate that higher ESP requirements
for testing would be more representative of all CUACs and CUHPs in the
field. The ESP requirements included in the ACUAC and ACUHP Working
Group TP Term Sheet reflect consensus among Working Group members
regarding higher ESP requirements for testing. The AHRI 1340-202X Draft
specifies provisions for determining the IVEC and IVHE metrics for
double-duct systems, ECUACs, and WCUACs, including higher ESP
requirements for testing consistent with

[[Page 56410]]

the ACUAC and ACUHP Working Group TP Term Sheet. Because the ACUAC and
ACUHP Working Group TP Term Sheet does not include provisions for
testing ECUACs and WCUACs, the term sheet does not include ESP
requirements for testing equipment with cooling capacity less than
65,000 Btu/h. The AHRI 1340-202X Draft includes an ESP requirement of
0.5 in H<INF>2</INF>O for testing ECUACs and WCUACs with cooling
capacity less than 65,000 Btu/h, which is consistent with the ESP
requirement specified in AHRI 210/240-2023 for comparable air-cooled
equipment. DOE has tentatively concluded that the ESP requirements
specified in AHRI 1340-202X Draft represent industry consensus for
testing CUACs and CUHPs and provide a more representative measure of
energy efficiency. Therefore, as discussed in sections III.F.4 and
III.F.5 of this NOPR, DOE is proposing to adopt the ESP requirements
specified in AHRI 1340-202X Draft as part of the IVEC and IVHE metrics.
f. Damper Leakage, Energy Recovery Systems, and Crankcase Heaters
In response to the May 2022 TP/ECS RFI, DOE received several
comments recommending that damper leakage, energy recovery systems, and
crankcase heaters be addressed in the test procedure for ACUACs and
ACUHPs.
NEEA recommended that DOE create a test procedure that accounts for
energy losses and gains from auxiliary components, considers energy
saved from increased enclosure insulation, and considers variation
alongside potentially incorporating CSA P.8, Thermal efficiencies of
industrial and commercial gas-fired packaged furnaces. (NEEA, EERE-
2022-BT-STD-0015-0013, at pp. 2-6) NEEA highlighted the significant
energy savings potential of heat recovery ventilation (HRV) and energy
recovery ventilation (ERV) systems. NEEA stated that its research
indicates such systems can reduce energy use by 24 percent in
commercial warm air furnaces in Northwest climate zones. Accordingly,
NEEA recommended that energy recovery be incorporated into the test
procedure and performance metric for CUACs and CUHPs. Id. With regard
to insulation, NEEA stated that while building codes such as ASHRAE
90.1 stipulate maximum damper leakage, the requirements do not apply to
the resale market, causing a significant number of units available
today to have significantly higher leakage rates than code
requirements. Id. NEEA recommended that DOE investigate the savings
potential of increased insulation and account for its benefit across
all operating modes in test procedure and efficiency metrics, as non-
conditioning operating periods are not currently accounted for. Id.
NEEA stated that its research indicates that increased enclosure
insulation can improve heating season energy savings, and that NEEA
expects there would be cooling season savings as well that are not
currently accounted for. Id. NEEA provided examples of subcomponent
performance characteristics that could be used as part of a whole box
metric approach, including AHRI 1060 for energy recovery, ANSI/AMCA
Standard 500-D-18 for damper leakage, and AHRI 1350 for evaluation of
enclosure insulation material and thickness for casing loss. Id. NEEA
recommended that DOE consider the approach implemented in CSA P.8 to
account for different outdoor air configurations, which could be
emulated to account for different percentages of ventilation air
without adding additional test burden. Id.
The CA IOUs expressed concern that energy use of equipment
components, such as crankcase heaters, is significant and not
represented in the IEER metric. (CA IOUs, EERE-2022-BT-STD-0015-0012,
at p. 6) The CA IOUs therefore recommended that off-mode and standby
energy consumption be accounted for when updating the CUAC/HP test
procedure and metric. Id.
As discussed, the Working Group assessed the impact of energy from
additional operating modes, as well as crankcase heaters and controls
power, and the metrics recommended in the ACUAC and ACUHP Working Group
TP Term Sheet include: (1) in the IVEC metric--economizer-only cooling,
cooling season ventilation mode, crankcase heat operation, and controls
power in unoccupied no-load cooling season hours; and (2) in the IVHE
metric--heating season ventilation mode, crankcase heat operation, and
controls power in unoccupied no-load heating season hours. (See EERE-
2022-BT-STD-0015-0065) Additionally, damper leakage was discussed
during the Working Group meetings, and the Working Group ultimately
voted not to address this issue in the IVEC and IVHE metrics. (See
EERE-2022-BT-STD-0015-0055, pp. 7-9) While cabinet insulation and the
effects of ERVs and HRVs were discussed during the Working Group
discussions, no proposals were made to include them in the new metrics.
All members of the Working Group voted to recommend inclusion of the
IVEC and IVHE metrics in the DOE test procedure for ACUACs and ACUHPs.
DOE has tentatively determined that the issues regarding additional
operating modes raised by commenters are adequately addressed by
provisions in the ACUAC and ACUHP Working Group TP Term Sheet, and
these provisions are also included in the AHRI 1340-202X Draft.
Further, at this time DOE lacks clear and convincing evidence to
justify proposing any deviations from the IVEC and IVHE metrics
specified in AHRI 1340-202X Draft to address damper leakage, cabinet
insulation, or ERVs and HRVs. Therefore, DOE proposes to adopt the IVEC
and IVHE metrics specified in AHRI 1340-202X Draft in appendix A1.
g. Controls Verification Procedure
In response to the May 2022 TP/ECS RFI, DOE also received several
comments regarding recommendations for a controls verification
procedure. The CA IOUs, ASAP and ACEEE, and NEEA suggested that DOE
consider a controls verification procedure (CVP) in the DOE test
procedure. (CA IOUs, EERE-2022-BT-STD-0015-0012, at p. 5; ASAP and
ACEEE, EERE-2022-BT-STD-0015-0011, at pp. 2-3; NEEA, EERE-2022-BT-STD-
0015-0013, at p. 5) Specifically, the CA IOUs recommended that DOE
consider a CVP similar to the one developed for variable refrigerant
flow multi-split systems (VRF multi-split systems) to validate that the
controls used within CUACs and CUHPs with variable speed compressors
are used effectively. (CA IOUs, EERE-2022-BT-STD-0015-0012, at p. 5)
ASAP and ACEEE stated that the CVP should include requirements for
testing under native controls to better reflect performance of
equipment in the field. (ASAP and ACEEE, EERE-2022-BT-STD-0015-0011, at
pp. 2-3) ASAP and ACEEE stated that this would mirror the CVP included
in the December 2021 test procedure NOPR for VRF multi-split systems
(See 86 FR 70644) and the native control requirement in the residential
cold climate heat pump challenge in the September 2021 specifications.
Id. NEEA recommended that DOE consider a verification procedure to test
that economizer controls operate as intended. (NEEA, EERE-2022-BT-STD-
0015-0013, at p. 5) Due to what NEEA asserted is a significant energy
savings opportunity of economizer cooling if the controls are verified,
NEEA recommended that economizers be incorporated into the efficiency
metric through a calculation-based approach. Id.
DOE notes that members from NEEA, ASAP, and the CA IOUs were
involved during the Working Group negotiations

[[Page 56411]]

and provided input on the included test procedure requirements. The
resulting ACUAC and ACUHP Working Group TP Term Sheet does not contain
any provisions for a CVP and was agreed upon by all members of the
Working Group. As such, DOE believes that the issues raised by these
stakeholders are resolved on this matter. Further, commenters did not
provide sufficient information that would justify or inform development
of a CVP for CUACs and CUHPs, and at this time, DOE lacks clear and
convincing evidence to propose any test procedure amendments that
deviate from the AHRI 1340-202X Draft to address controls verification.
h. Heating Efficiency Metric
In the May 2022 TP/ECS RFI, DOE stated that it was considering
whether incorporating heating performance at temperatures lower than 47
[deg]F would improve the representativeness of the DOE test procedure
for ACUHPs, and how such performance would differ between CUHPs with
different types of supplementary heat (e.g., electric resistance heat
and furnaces) and the climate regions in which CUHPs are typically
installed. As such, in the May 2022 TP/ECS RFI, DOE requested comment
on data relating to CUHP shipments and typical regions they are shipped
to, distribution of heating types shipped with CUHPs, and the lowest
outdoor temperatures CUHPs are expected to operate at alongside cut in
and cut out temperature data. 87 FR 31743, 31750-31753.
Carrier provided data showing the shipment-weighted market share by
building type for CUACs and CUHPs; however, Carrier noted that the
actual shipment data by building type would be best obtained from AHRI
for the whole U.S. industry. (Carrier, EERE-2022-BT-STD-0015-0010, at
p. 13)
In response to the request for comment regarding shipment data of
CUHPs, Lennox and the CA IOUs commented that the market for CUHPs is
growing alongside electrification efforts, but still represents a small
fraction of the overall CUAC and CUHP market. (Lennox, EERE-2022-BT-
STD-0015-0009, at pp. 3-4; CA IOUs, EERE-2022-BT-STD-0015-0012, at pp.
4-5) Additionally, Lennox stated that the CUHP market is primarily
concentrated in the south and southwestern regions of the country, with
the majority located in California and Arizona. Id. Lennox acknowledged
the importance of CUHP market growth and test procedure improvements
but recommended that DOE fully evaluate industry capability and
incremental burden associated with test procedure amendments to prevent
undue burden. Id.
NYSERDA noted that in an effort to decarbonize, the Climate Action
Council of New York set a 2030 goal that heat pumps should provide
space heating and cooling for 10 percent to 20 percent of commercial
space statewide, and that heat pumps should become the majority of new
purchases for space and water heating by the late 2020s. (NYSERDA,
EERE-2022-BT-STD-0015-0007, at pp. 1-2)
Carrier stated that the commercial heat pump market is generally
limited to models under 20 tons because the demand for large heat pumps
in commercial buildings is currently very small. (Carrier, EERE-2022-
BT-STD-0015-0010, at p. 8) Carrier noted that commercial load profiles
are significantly different than residential buildings, that commercial
buildings have much higher cooling loads than residential buildings,
and that commercial buildings tend to operate during the day and are
often unoccupied during the evening when temperatures are lower. Id.
In response to the request for comment regarding the distribution
of supplementary heating types shipped with CUHPs, Carrier stated that
currently, it only provides CUHPs with electric heat as backup, mostly
because the different load profiles in commercial buildings are more
cooling intensive. (Carrier, EERE-2022-BT-STD-0015-0010, at p. 8)
Carrier also stated that with the growing interest in use of heat pumps
in colder climates, it is evaluating the use of backup gas heat. Id.
Lennox stated that it does not offer CUHP products with factory-
installed supplementary electric heat and described the difficulty in
tracking field-installed electric heat accessories. (Lennox, EERE-2022-
BT-STD-0015-0009, at p. 4) Lennox noted that dual-fuel CUHP products
with factory-installed gas furnaces comprise less than 1 percent of the
CUHP and CUAC markets but could expand as CUHPs are implemented in
climates with heating capacity requirements exceeding current CUHP
abilities. Id.
In response to the request for data on the operating temperatures
for CUHPs, AHRI stated that the lowest outdoor temperatures at which
CUHPs typically operate in mechanical heating mode would be between 5
[deg]F and 15 [deg]F, and that the cut-out temperature is not dependent
on supplementary heat. (AHRI, EERE-2022-BT-STD-0015-0008, at p. 4) AHRI
stated that the purpose of supplementary heat is to provide comfort
conditions to buildings, and that a compressor cut-out temperature is
required to protect equipment. Id. Carrier stated that currently, its
CUHPs are rated to operate down to -10 [deg]F with a few limited to -5
[deg]F and 0 [deg]F, and that at these very low temperatures, auxiliary
electric heat is required. (Carrier, EERE-2022-BT-STD-0015-0010, at p.
8) Carrier also stated that currently, there is no set temperature for
mechanical heating lockout. Id. Lennox stated that industry compressor
cut-out temperatures range from over 15 [deg]F to -15 [deg]F depending
on unit design. (Lennox, EERE-2022-BT-STD-0015-0009, at p. 4) Lennox
commented that with electric heating, cut-out temperatures are
typically set to the lowest available setting, while compressor cut-out
temperature is normally more flexible and typically set to a higher
temperature with furnace supplementary heating. Id.
In addition to the data and information provided regarding specific
heat pump issues, DOE received recommendations from multiple
stakeholders regarding potential new heating efficiency metrics. The CA
IOUs encouraged DOE to adopt an updated heating metric to match the
expected increase in market share and recommended using a metric that
is representative of an average use cycle. (CA IOUs, EERE-2022-BT-STD-
0015-0012, at pp. 4-5) Additionally, the CA IOUs expressed support for
a seasonal heating metric, similar to HSPF2 for consumer heat pumps,
which could account for performance at different ambient conditions,
defrost operation, and standby modes. Id. The CA IOUs also noted that
separate product categories could also be considered, such as for cold-
climate CUHPs. Id.
NYSERDA stated that a heating efficiency metric could utilize
heating-specific weighting factors similar to those used in the
approach for IEER calculations and could take into account heating mode
tests at all three conditions, alongside proposing two new required
test conditions. (NYSERDA, EERE-2022-BT-STD-0015-0007, at pp. 1-2)
NYSERDA also recommended the new metric utilize fractional heating bin
hours for a representative region, and account for the typical load
profiles for the 16 DOE commercial prototype buildings. Id.
Lennox asserted that reasonably designed test procedure amendments
could encourage CUHP product improvements in low temperature
performance and accelerate market expansion. (Lennox, EERE-2022-BT-STD-
0015-0009, at p. 4)
Specifically, NYSERDA, the CA IOUs, and ASAP and ACEEE supported an
update to the CUHP heating metric to

[[Page 56412]]

account for performance under 17 [deg]F and 5 [deg]F ambient
conditions. (NYSERDA, EERE-2022-BT-STD-0015-0007, at pp. 1-2; CA IOUs,
EERE-2022-BT-STD-0015-0012, at p. 4; ASAP and ACEEE, EERE-2022-BT-STD-
0015-0011, at p. 1) All three groups recommended that DOE incorporate a
test at 5 [deg]F as an optional test condition. Id. The CA IOUs also
recommended accounting for defrost performance, and that DOE track the
development of ASHRAE RP-1831 ``Validation of a Test Method for
Applying a Standardized Frost Load on a Test Evaporator in a Test
Chamber with an Operating Conditioning System'' to consider whether it
can help the development of a test procedure that incorporates defrost
performance. (CA IOUs, EERE-2022-BT-STD-0015-0012, at p. 4)
Carrier stated that it is not aware of how many test laboratories
in the United States have the capabilities of testing on ACUHPs at low
ambient conditions. (Carrier, EERE-2022-BT-STD-0015-0010, at p. 9)
Carrier asserted that if DOE were to require testing at lower ambient
conditions for ACUHPs, manufacturers and third-party labs may be
required to invest substantial capital in psychrometric room upgrades.
Id.
During the Working Group ASRAC negotiations, extensive discussions
were held and analyses were conducted on improving the
representativeness of the heating metric for ACUHPs by creating a
seasonal metric. As a result of these discussions and analyses, Working
Group members reached consensus on the IVHE metric to better represent
ACUHP energy use across a range of operation conditions, and specified
test conditions and procedures for determining IVHE in the ACUAC and
ACUHP Working Group TP Term Sheet. The tests for determining IVHE
include required and optional tests at varying load levels (i.e., full-
load, part-load, and for variable-speed equipment, boost compressor
speed) and outdoor air dry-bulb temperatures (specifically 47 [deg]F,
17 [deg]F, and 5 [deg]F). The IVHE metric also accounts for defrost
operation by including a defrost degradation coefficient for low-
temperature operation (less than 40 [deg]F). DOE has tentatively
determined that the IVHE metric included in the ACUAC and ACUHP Working
Group TP Term Sheet and the AHRI 1340-202X Draft addresses concerns
raised by commenters, and as discussed further in section III.F.5 of
this NOPR, DOE is proposing to adopt the IVHE metric as specified in
the AHRI 1340-202X Draft in appendix A1.
2. Test Conditions Used for Current Metrics in Appendix A
As discussed, DOE proposes to update the current test procedure for
CUACs and CUHPs (which DOE proposes to specify for ACUACs and ACUHPs,
ECUACs, and WCUACs in appendix A) to reference the updated industry
test standard AHRI 340/360-2022 and retain the current metrics for
CUACs and CUHPs. AHRI 340/360-2022 designates certain test conditions
for test procedures characterized as ``standard rating tests'' and
certain other test conditions for test procedures characterized as
``performance operating tests.'' The ``standard rating tests'' are used
for determining representations of cooling capacity, heating capacity,
and cooling and heating efficiencies. The ``performance operating
tests'' evaluate other operating conditions, such as ``maximum
operating conditions'' (see section 8 of AHRI 340/360-2022), which DOE
is not proposing to include in the DOE test procedure. Specifically,
Table 6 of AHRI 340/360-2022 specifies test conditions for standard
rating and performance operating tests for CUACs and CUHPs. The
relevant conditions for EER and IEER cooling tests are those referred
to as ``standard rating conditions'' in AHRI 340/360-2022. To clarify
this distinction, DOE proposes to specify explicitly in section 3 of
appendix A that the cooling test conditions used for representations as
required under the DOE regulations are: (1) for equipment subject to
standards in terms of EER, the ``Standard Rating Conditions, Cooling''
conditions specified in Table 6 of AHRI 340/360-2022; and (2) for
equipment subject to standards in terms of IEER, the ``Standard Rating
Conditions, Cooling'' and ``Standard Rating Part-Load Conditions
(IEER)'' conditions specified in Table 6 of AHRI 340/360-2022.
For heating mode tests of CUHPs, Table 6 of AHRI 340/360-2022
includes ``Standard Rating Conditions'' for both a ``High Temperature
Steady-state Test for Heating'' and a ``Low Temperature Steady-state
Test for Heating'' (conducted at 47 [deg]F and 17 [deg]F outdoor air
dry-bulb temperatures, respectively). To clarify which conditions are
applicable for representations as required under the DOE regulations,
DOE proposes to specify explicitly in section 3 of appendix A that the
heating test conditions used for compliance are the ``Standard Rating
Conditions (High Temperature Steady-state Heating)'' conditions
specified in Table 6 of AHRI 340/360-2022. Further, DOE proposes to
also include the low-temperature (i.e., 17 [deg]F) heating test
condition specified in Table 6 of AHRI 340/360-2022 (referred to as
``Low Temperature Steady-state Heating'') in the proposed test
procedure and specify in section 3 of appendix A that representations
of COP at this low-temperature heating condition are optional.
3. Test Conditions Used for New Metrics in Proposed Appendix A1
As discussed, DOE is proposing to include the new test procedure
recommended in the ACUAC and ACUHP Working Group TP Term Sheet and
included in the AHRI 1340-202X Draft in a new appendix A1. This
proposal includes adopting the new IVEC and IVHE metrics discussed in
sections III.F.4 and III.F.5 of this NOPR.
The AHRI 1340-202X Draft designates certain test conditions for
test procedures characterized as ``standard rating tests'' and certain
other test conditions for test procedures characterized as
``performance operating tests.'' The ``standard rating tests'' are used
for determining representations of cooling capacity, heating capacity,
and cooling and heating efficiencies. The ``performance operating
tests'' evaluate other operating conditions, such as ``maximum
operating conditions'' (see section 8 of AHRI 1340-202X Draft), which
DOE is not proposing to include in the DOE test procedure at appendix
A1. Specifically, Table 7 of AHRI 1340-202X Draft specifies test
conditions for standard rating and performance operating tests for
CUACs and CUHPs. The relevant test conditions for IVEC tests, as well
as EER2 representations, are those referred to as ``standard rating
conditions'' in the AHRI 1340-202X Draft. To clarify this distinction,
DOE proposes to specify explicitly in section 3 of appendix A1 that the
cooling conditions used for representations as required under the DOE
regulations are the ``Standard Rating Conditions, Cooling'' and
``Standard Rating Part-Load Conditions (IVEC)'' specified in Table 7 of
AHRI 1340-202X Draft. Additionally, DOE proposes to include provisions
for optional representations of EER2.
For heating mode tests of ACUHPs, Table 7 of the AHRI 1340-202X
Draft includes ``Standard Rating Conditions, Heating'' for three
outdoor temperature conditions at 47 [deg]F, 17 [deg]F, and 5 [deg]F.
Additionally, the table includes ``Standard Rating Part-Load Conditions
(IVHE),'' which includes optional part load conditions for rating units
with the IVHE metric. The required test conditions for IVHE
representations are the ``Standard Rating Conditions Heating'' at 47
[deg]F and 17 [deg]F. The optional test conditions for IVHE

[[Page 56413]]

representations are the ``Standard Rating Conditions Heating'' at 5
[deg]F and ``Standard Rating Part-Load Conditions (IVHE)''. To clarify
this, DOE proposes to specify explicitly in section 3 of appendix A1
that the heating conditions used for representations as required under
the DOE regulations are the ``Standard Rating Conditions Heating'' at
47 and 17 [deg]F specified in Table 7 of AHRI 1340-202X Draft. Further,
DOE proposes to also include the 5 [deg]F heating test condition as
well as the part load test conditions specified in Table 7 of AHRI
1340-202X Draft (referred to as ``Standard Rating Conditions Heating (5
[deg]F ambient)'' and ``Standard Rating Part-Load Conditions (IVHE)''
respectively) in the proposed test procedure and specify in section 3
of appendix A1 that testing to the low-temperature heating conditions
and the part load conditions are optional for representations of IVHE.
Additionally, DOE proposes to include provisions for optional
representations of COP2<INF>47</INF>, COP2<INF>17</INF>, and
COP2<INF>5</INF> at the 47, 17, and 5 [deg]F heating test conditions
previously discussed.
4. IVEC
The following section provides a summary of the development and
final recommendations regarding the IVEC cooling metric proposals in
the ACUAC and ACUHP Working Group TP Term Sheet and DOE's corresponding
proposals for inclusion in the appendix A1 test procedure.
As discussed, for the newly proposed cooling metric, the Working
Group determined to modify the climate zones and building types
accounted for in the test procedure compared to those included in the
current DOE test procedure. To do so, the Working Group utilized hour-
based weighting factors. To develop these weighting factors, members of
the Working Group used building modeling developed by Carrier that was
based on 10 ASHRAE 90.1 building prototypes across all U.S. climate
zones. (See EERE-2022-BT-STD-0015-0019) This resulted in hour-based
weighting factors, which are provided in Recommendation #2 of the ACUAC
and ACUHP Working Group TP Term Sheet.
The ACUAC and ACUHP Working Group concluded that including
economizer-only cooling and cooling season ventilation operating modes
in a seasonal cooling metric would improve the representativeness for
ACUACs and ACUHPs. Appendix B of the ACUAC and ACUHP Working Group TP
Term Sheet provides the recommended calculation method for the IVEC
method and includes sections specifying the methods for including
ventilation and economizer-only cooling operation in the calculation of
IVEC.
As discussed in section III.F.1.e of this NOPR, the Working Group
also considered ESP requirements for the newly proposed IVEC and IVHE
metrics. Stakeholders indicated the need for higher ESP requirements to
improve representativeness of field performance. Additionally,
stakeholders discussed the importance of maintaining uniformity in
testing of units at higher ESP conditions. (See EERE-2022-BT-STD-0015-
0062 at p. 11) The ESP requirements agreed to by the Working Group are
provided in Recommendation #12 of the ACUAC and ACUHP Working Group TP
Term Sheet and include the following:
1. Higher ESP requirements for testing: As discussed previously,
the minimum ESP conditions recommended by the Working Group are
provided in Table III.1.

Table III.1--Minimum ESP Requirements for IVEC and IVHE Recommended by
the ACUAC and ACUHP Working Group
------------------------------------------------------------------------
ESP (in
Rated cooling capacity H2O)
------------------------------------------------------------------------
>=65 and <135 kBtu/h........................................ 0.75
>=135 and <240 kBtu/h....................................... 1.0
>=240 and <280 kBtu/h....................................... 1.0
>=280 and <760 kBtu/h....................................... 1.5
------------------------------------------------------------------------

2. Economizer pressure drop: ASHRAE 90.1-2022 requires the use of
economizers for comfort cooling applications for almost all U.S.
climate zones. The analysis conducted by Carrier in support of the
Working Group indicates that over 96 percent of buildings require the
use of economizers. Economizers installed in CUACs and CUHPs add
internal static pressure that the indoor fan has to overcome, even when
the economizer dampers are closed. The current DOE test procedure does
not require the installation of an economizer on a tested unit, and DOE
is aware that manufacturers generally do not test CUACs and CUHPs with
economizers installed. The ESP requirements specified by the current
DOE test procedure are the same regardless of whether a unit is tested
with or without an economizer. As such, testing a unit without an
economizer does not reflect the total static pressure that would be
experienced in the field for installations that require the use of an
economizer. In order to better represent the fan power of ACUACs and
ACUHPs that are typically installed with economizers, the Working Group
recommended that for all units tested without an economizer installed,
0.10 in. H<INF>2</INF>O shall be added to the full load ESP values
specified in Table III.1.
3. Return and supply static split requirements: Test procedures for
CUACs and CUHPs include ESP requirements that reflect the total ESP
applied within the return and supply ductwork of the test setup. The
current Federal test procedure does not specify requirements for how
ESP is distributed during testing (i.e., the relative contribution from
return ductwork versus supply ductwork). Given the recommendation to
increase the required ESP levels for testing (as discussed in section
III.F.1.e of this document), the Working Group concluded that the
higher ESP conditions could cause variability in test results if the
distribution of ESP between return ductwork and supply ductwork were
not specified in the revised test procedure. To ensure repeatable and
reproducible testing conditions for CUAC and CUHP units, the Working
Group recommended specifying that ESP requirements be split with 25
percent applied in the return ductwork and the remaining 75 percent
applied in the supply ductwork. The Working Group further recommended
that the fraction of ESP applied in the return ductwork shall have a -
5/+0 percent tolerance (i.e., the return static must be within 20 to 25
percent of the total ESP) for the full-load cooling test. In a case
where there is no additional restriction on the return duct and more
than 25 percent of the ESP is already applied in the return ductwork
without a restriction, then greater than 25 percent ESP in the return
ductwork would be allowed. Once set for the full-load cooling test,
these restriction settings shall remain unchanged for the other cooling
and heating tests conducted.
To incorporate the various changes involved in testing requirements
and weighting factors already discussed, the Working Group created the
IVEC metric provided in Recommendation #1 with further specifications
in appendix B of the ACUAC and ACUHP Working Group TP Term Sheet. The
IVEC metric is essentially a summation formula analogous to the
seasonal energy efficiency ratio 2 (SEER2) metric designated for
residential central air conditioner (CAC) equipment. (See appendix M1
to subpart B of part 430 ``Uniform Test Method for Measuring the Energy
Consumption of Central Air Conditioners and Heat Pumps'') Specifically,
the IVEC metric is calculated by dividing the total annual

[[Page 56414]]

cooling capacity by the total annual energy use. Key aspects
encompassed in the proposed IVEC metric include the following:
1. Accounting for energy consumed in different modes: The IVEC
metric includes energy use during mechanical cooling, integrated
mechanical and economizer cooling, economizer-only cooling, cooling
season ventilation, unoccupied no-load hours, and heating season
operation of crankcase heat (for CUACs only). Appendix B of the ACUAC
and ACUHP Working Group TP Term Sheet specifies instructions for
determining energy consumption during each mode.
2. Testing parameters: The ACUAC and ACUHP Working Group TP Term
Sheet further specifies instructions in appendix B for the mechanical
cooling tests at each target mechanical load. These methodologies and
tolerances mirror those specified in AHRI 340/360-2022, including a 3-
percent tolerance on the target mechanical load for part-load tests,
and in cases when the target mechanical load cannot be met within
tolerance, instructions for using interpolation and cyclic degradation
to determine the performance at the target test point.
3. Target load percentages: Recommendation #4 of the ACUAC and
ACUHP Working Group TP Term Sheet includes target conditions for
testing, including load percentages for testing units at part-load
conditions. For each bin, the specified target load percent (% Loadi)
reflects the average load as a percentage of the full-load capacity for
that bin met by using all modes of cooling, and is used for determining
total annual cooling provided in the numerator of the IVEC equation.
The target mechanical load percent (% Loadi, mech) is the average load
for each bin met only through mechanical cooling (i.e., mechanical-only
cooling and the mechanical portion of integrated mechanical and
economizer cooling) and is the target load fraction used for the part-
load cooling test for each bin.
As mentioned, the IVEC metric includes the annual operation of
crankcase heaters for CUACs and CUHPs. Appendix B of the ACUAC and
ACUHP Working Group TP Term Sheet further specifies the accounting of
crankcase heater energy consumption in each operating mode.
Recommendation #2 of the ACUAC and ACUHP Working Group TP Term Sheet
specifies hour-based weighting factors to account for crankcase heat
operation in unoccupied no-load cooling season hours for CUACs and
CUHPs as well as heating season hours for CUACs. Appendix B of the
ACUAC and ACUHP Working Group TP Term Sheet also specifies that for
part-load cooling tests, crankcase heat is accounted for in power
measurements of higher stage compressors that are staged off during
testing, while crankcase heat operation of lower-stage compressors when
cycled off as well as crankcase heat operation in other operating modes
is calculated using the certified crankcase heater power.
The IVEC metric also accounts for a 15-percent oversizing factor.
Accordingly, the target load percentages specified in Recommendation #4
include this 15 percent oversizing factor. Additionally, the A test
condition is excluded from the IVEC calculation; however, the A test is
still a required test point for determining full load capacity.
IVEC includes outdoor and return air dry-bulb and wet-bulb test
temperatures that differ from those used in the current test procedure
for determining IEER, as shown in Table III.2.

Table III.2--IEER and IVEC Test Temperatures
----------------------------------------------------------------------------------------------------------------
IEER test conditions IVEC test conditions
---------------------------------------------------------------------------
Return air Return air
Test point Outdoor air dry temperature (dry Outdoor air dry temperature (dry
bulb temperature bulb/wet bulb) bulb temperature bulb/wet bulb)
([deg]F) ([deg]F) ([deg]F) ([deg]F)
----------------------------------------------------------------------------------------------------------------
A................................... 95 80/67 95 80/67
B................................... 81.5 80/67 85 77/64
C................................... 68 80/67 75 77/64
D................................... 65 80/67 65 77/64
----------------------------------------------------------------------------------------------------------------

The IVEC metric also limits the minimum airflow that can be used
for testing. This minimum airflow limit calculation method is based on
the average ventilation rate determined in building modeling performed
to develop IVEC and is a function of the full-load cooling capacity.
Unlike AHRI 340/360-2022 (see section 6.1.3.4.5), the provisions for
determining IVEC do not specify separate test provisions for setting
airflow during part-load tests of MZVAV units. Rather, the part-load
airflow used for testing all CUACs and CUHPs would be based on the
certified part-load cooling airflow.
Based on the discussions in the Working Group, DOE understands that
the changes recommended for the IVEC metric are intended to result in
an efficiency metric that is more representative of CUAC and CUHP
operation. Therefore, DOE tentatively agrees with the approach
recommended by the Working Group and is proposing to adopt the IVEC
metric in appendix A1 as specified in the AHRI 1340-202X Draft
(including the provisions discussed in section III.F.6 of this NOPR
that were not included in the ACUAC and ACUHP Working Group TP Term
Sheet).
5. IVHE
The following section provides a summary of the development and
final recommendations regarding the IVHE heating metric specified in
the ACUAC and ACUHP Working Group TP Term Sheet.
The IVHE metric specified in the ACUAC and ACUHP Working Group TP
Term Sheet differs from the COP heating efficiency metric specified in
the current DOE test procedure through the inclusion of heating season
operating modes not currently accounted for, a combined seasonal
performance metric rather than individual ratings at specific
temperature conditions, and additional optional test conditions. In
alignment with the development of the IVEC metric described in section
III.F.4 of this NOPR, the Working Group determined to utilize hour-
based weighting factors to account for heating loads across more
building types and climate zones than are included in the current DOE
test procedure. The building heating load lines and hours developed for
the IVHE metric rely on a similar ASHRAE 90.1 building and climate zone
analysis as the one conducted for the IVEC metric development.
Additionally, in developing the heating load line that the hour-based
weighting factors rely on,

[[Page 56415]]

the Working Group utilized the previously discussed 15-percent
oversizing factor and assumed a heat to cool ratio of 1 as outlined in
Recommendation #8 (i.e., assumed the peak building cooling load equals
the peak building heating load).
The heating rating requirements recommended in the ACUAC and ACUHP
Working Group TP Term Sheet include several distinct provisions
regarding testing requirements from the existing DOE test procedure. In
the current DOE test procedure, CUHPs are required to be tested only at
a 47 [deg]F full-load condition to generate a COP rating.
Recommendation #9 of the ACUAC and ACUHP Working Group TP Term Sheet,
however, introduces several provisions with significant differences
from the existing DOE test procedure. First, the recommendation
includes required testing at 47 [deg]F and 17 [deg]F full load
conditions, aligning with those previously specified in AHRI 340/360-
2022. Additionally, the recommendation introduces optional part load
test conditions at both 47 [deg]F and 17 [deg]F temperature conditions
as well as test conditions for optional testing at a 5 [deg]F full load
condition. Finally, the recommendation includes test requirements for
optional boost tests at the 17 [deg]F and 5 [deg]F test conditions for
variable speed units. Additionally, the IVHE metric incorporates two
operating modes previously excluded from the DOE test procedure:
heating season ventilation mode and supplemental electric resistance
heat operation. Lastly, the IVHE test conditions rely on the same ESP
requirements per capacity bin as those specified for IVEC, as detailed
in Recommendation #12. The airflow provisions pertaining to IVEC
mentioned in section III.F.4 of this NOPR (i.e., a limit on minimum
airflow used for testing and no separate test provisions for MZVAV
units) apply to the test provisions for the IVHE metric as well.
The results from optional and required testing as well as the newly
included operating modes are included in the calculation of the IVHE
metric utilizing the weighting factors outlined in Recommendation #8
and calculation methods from appendix C of the ACUAC and ACUHP Working
Group TP Term Sheet. The calculation methods for IVHE that implement
these changes are further detailed in the paragraphs that follow.
The IVHE metric includes contributions from both mechanical and
resistance heating to meet building heating load. Similar to the IVEC
calculation approach, the IVHE metric is calculated by dividing the
total annual building heating load by the total annual energy use.
Recommendations #8, #9 and #10, as well as appendices B and C of
the ACUAC and ACUHP Working Group TP Term Sheet, provide the
calculation methods for the IVHE metric. The proposed hour-based
weighting factors and bin temperatures for IVHE are included in
Recommendation #8 of the ACUAC and ACUHP Working Group TP Term Sheet,
which specifies 10 distinct load-based bins alongside weighting factors
for heating season ventilation and operation of crankcase heat in
unoccupied no-load heating season hours. The calculation methods
outlined for the IVHE metric in the ACUAC and ACUHP Working Group TP
Term Sheet are specified as the following:
1. Building load calculation: Recommendation #8 includes the
calculation method for the building load in each load bin based on the
measured full-load cooling capacity.
2. Interpolation between temperatures: Appendix C of the ACUAC and
ACUHP Working Group TP Term Sheet specifies interpolation instructions
for the various test temperatures specified in Recommendation #8.
Interpolation instructions are specified for bins with temperatures
between 17 [deg]F and 47 [deg]F. Appendix C also includes the following
instructions for bins with temperatures less than 17 [deg]F: (1)
interpolation instructions to be used if the optional 5 [deg]F test is
conducted, and (2) extrapolation instructions utilizing the 47 [deg]F
and 17 [deg]F test data to be used if the 5 [deg]F test is not
conducted.
3. Determination of heating stage, auxiliary heat, and cyclic
degradation: For load bins in which the calculated building load
exceeds the highest-stage mechanical heating capacity determined for
the bin temperature, appendix C of the ACUAC and ACUHP Working Group TP
Term Sheet includes calculation methods for determining the power
required by auxiliary resistance heat and is included in the overall
IVHE calculation. For load bins in which the calculated building load
is lower than the lowest-stage mechanical heating capacity determined
for the bin temperature, appendix C of the ACUAC and ACUHP Working
Group TP Term Sheet includes calculation methodology for calculating
power and incorporating cyclic degradation with a cyclic degradation
factor of 0.25. This cyclic degradation methodology is consistent with
the methodology specified in appendix M1 to subpart B of 10 CFR part
430 for residential central heat pumps. For load bins in which the
calculated building load is in between the lowest-stage and highest-
stage mechanical heating capacities determined for the bin temperature,
appendix C of the ACUAC and ACUHP Working Group TP Term Sheet includes
calculations for determining power based on interpolation between
performance of mechanical heating stages.
4. Defrost degradation: The capacity calculations for all load bins
with temperatures less than 40 [deg]F include a defrost degradation
coefficient, with calculations specified in appendix C of the ACUAC and
ACUHP Working Group TP Term Sheet.
5. Cut-out factor: Recommendation #10 of the ACUAC and ACUHP
Working Group TP Term Sheet specifies that manufacturers will certify
cut-in and cut-out temperatures, or the lack thereof, to DOE to ensure
resistance-only operation is included at temperatures below which
mechanical heating would not operate. This restriction is implemented
in calculations through a cut-out factor included in appendix C. DOE is
not proposing to amend the certification or reporting requirements for
ACUHPs in this NOPR to require reporting cut-in and cut-out
temperatures. Instead, DOE may consider proposals to amend the
certification and reporting requirements for this equipment under a
separate rulemaking regarding appliance and equipment certification.
6. Crankcase heater power contribution: In alignment with the
inclusion of crankcase heater power contribution in IVEC, appendix C of
the ACUAC and ACUHP Working Group TP Term Sheet specifies a method for
incorporating crankcase heat power for all heating season operating
modes for ACUHPs. Specifically, for part-load heating tests, crankcase
heat is accounted for in power measurements of higher stage compressors
that are staged off during testing, while crankcase heat operation of
lower-stage compressors when cycled off as well as crankcase heat
operation in other operating modes is calculated using the certified
crankcase heater power.
Based on participation in the Working Group, DOE understands that
the changes recommended for the IVHE metric are intended to result in
an efficiency metric that is more representative of CUHP operation. As
discussed, DOE tentatively agrees with the approach recommended by the
Working Group and is proposing to adopt the IVHE metric in appendix A1,
as specified in the AHRI 1340-202X Draft (including the provisions
discussed in section III.F.6 of this NOPR

[[Page 56416]]

that were not included in the ACUAC and ACUHP Working Group TP Term
Sheet).
a. IVHE for Colder Climates
While stakeholder comments received (as discussed in section
III.F.1.h) indicate that the majority of current CUHP shipments are
concentrated in the south and southwestern regions of the country, it
is likely that in the future manufacturers will develop CUHPs that are
designed for operation in colder climates, and correspondingly that the
market for CUHPs in colder climates is expected to grow. Because the
IVHE metric is based on the US national average climate across all US
climate zones, the lowest bin temperature for calculating IVHE is 15.9
[deg]F, and a small fraction of heating hours are at colder
temperatures (i.e., 19 percent of heating hours are in a load bin with
a temperature colder than 32 [deg]F, and less than 1 percent of heating
hours are in a load bin with a temperature colder than 17 [deg]F).
As a result, the AHRI 1340-202X Draft includes provisions,
including weighting factors and temperature bins, for calculating a
colder climate-specific IVHE metric, designated as IVHE<INF>C</INF>,
which are distinct from the provisions used for IVHE. Specifically,
IVHE<INF>C</INF> was developed using the same building heating analysis
that was used to develop IVHE (as discussed in section III.F.5 of this
NOPR), but the IVHE<INF>C</INF> weighting factors and load bins were
developed using the results for climates zones 5 and above (i.e.,
climate zone 5 as well as all climate zones colder than climate zone
5), weighted by the share of the US population in each of those climate
zones. The use of only climate zones 5 and colder for IVHE<INF>C</INF>
results in the following, compared to IVHE: lower outdoor dry-bulb
temperature for each load bin, more heating season hours in all load
bins, and a higher heating season building load. Specifically, for
IVHE<INF>C</INF>, 56 percent of heating hours are in a load bin with a
temperature colder than 32 [deg]F, and 12 percent of heating hours are
in a load bin with a temperature colder than 17 [deg]F. Further,
because the defrost degradation coefficients specified in appendix C of
the ACUAC and ACUHP Working Group TP Term Sheet depend on the outdoor
temperature for each load bin (and IVHE<INF>C</INF> has colder bin
temperatures than IVHE), the AHRI 1340-202X Draft also specifies
separate defrost degradation coefficients for calculating
IVHE<INF>C</INF>. The temperatures and hours for each load bin for
calculating IVHE and IVHE<INF>C</INF> can be found in section 6.3.2 of
the AHRI 1340-202X Draft.
Given the potential for the development of CUHPs designed for
operation in colder climates and the expected increased number of
shipments of CUHPs into colder climates, DOE recognizes the utility in
having CUHP ratings for a separate IVHE metric that is specific to
colder climates. Correspondingly, DOE has tentatively concluded that
the IVHE<INF>C</INF> metric as specified in the AHRI 1340-202X Draft is
more representative of field conditions for CUHPs installed in colder
US climates. Therefore, DOE is proposing to adopt provisions for
determining the IVHE<INF>C</INF> metric in appendix A1 via reference to
the AHRI 1340-202X Draft, and to allow for optional representations of
IVHE<INF>C</INF> for CUHPs. Specifically, DOE is proposing that IVHE
would be the regulated metric when testing to appendix A1; therefore,
should DOE adopt amended standards for CUHPs in terms of IVEC and IVHE,
all CUHPs would be required to certify compliance with IVHE standards,
and additional representations of IVHE<INF>C</INF> would be optional.
6. Additions and Revisions to the IVEC and IVHE Metrics Not Included in
the Term Sheet
AHRI 1340-202X Draft includes several provisions regarding the new
IVEC and IVHE metrics that are not included in the ACUAC and ACUHP
Working Group TP Term Sheet. DOE notes that the ACUAC and ACUHP Working
Group TP Term Sheet includes provisions to allow changes to the
proposals in the term sheet if mistakes in the original recommendations
are identified through further analysis or discussion between
stakeholders. (See EERE-2022-BT-STD-0015-0065, Recommendations #2, #8,
#11) Further, the AHRI 1340-202X Draft includes a number of additional
test provisions that DOE has tentatively concluded are consistent with
the intent of the ACUAC and ACUHP Working Group TP Term Sheet, but
provide additional guidance for determining IVEC and IVHE. As
discussed, DOE is proposing to adopt AHRI 1340-202X Draft for
determining IVEC and IVHE in appendix A1, including these additional
provisions not specified in the ACUAC and ACUHP Working Group TP Term
Sheet. The following sections discuss these provisions in further
detail.
a. Cooling Weighting Factors Adjustment
Subsequent to the development of the ACUAC and ACUHP Working Group
TP Term Sheet, additional analysis of the building models used to
develop the weighting factors for the IVEC metric indicated that the
proposed weighting hours included in the ACUAC and ACUHP Working Group
TP Term Sheet are incorrect. Specifically, the weighting hour factors
in the ACUAC and ACUHP Working Group TP Term Sheet over-represent
mechanical-only cooling hours and underrepresent economizer-only and
integrated-economizer hours for all IVEC load bins. DOE presented
corrected weighting factors during the ACUAC and ACUHP standards
negotiations and no concerns were raised. (See EERE-2022-BT-STD-0015-
0078 at p. 8) These corrected IVEC weighting factors are included in
AHRI 1340-202X Draft. DOE is proposing to adopt AHRI 1340-202X Draft
for determining IVEC and IVHE in appendix A1, including these updated
IVEC weighting factors.
b. ESP Testing Target Calculation
Recommendation #12 of the ACUAC and ACUHP Working Group TP Term
Sheet includes an equation for determining adjusted ESP for cooling or
heating tests that use an airflow that differs from the full-load
cooling airflow. However, the equation specified in Recommendation #12
is missing a term for the full-load ESP. This equation is corrected in
AHRI 1340-202X Draft. DOE is proposing to adopt these provisions of
AHRI 1340-202X Draft for determining IVEC and IVHE in appendix A1,
including this corrected equation for determining adjusted ESP.
c. Test Instructions for Splitting ESP Between Return and Supply
Ductwork
As discussed previously, Recommendation #12 of the ACUAC and ACUHP
Working Group TP Term Sheet specifies that ESP shall be split between
return and supply ducts during testing, such that 25 percent of the ESP
is applied in the return ductwork. However, the ACUAC and ACUHP Working
Group TP Term Sheet does not contain explicit test setup instructions
specifying how to achieve the split in ESP between return and supply
ductwork. Section E11 of the AHRI 1340-202X Draft includes more
detailed instructions regarding the duct and pressure measurement
setup, the measurement and adjustment of the return static pressure,
and the restriction devices that can be used in the return ductwork to
achieve the required split of between 20 and 25 percent of the total
ESP applied to the return ductwork. The AHRI 1340-202X Draft also
includes test instructions for cases in which the ESP split is not
achieved in the first test as well as any exceptions to the specified
tolerance requirement. DOE has tentatively

[[Page 56417]]

concluded that these additional instructions will provide a more
consistent measurement of ESP and are aligned with the intent of
Recommendation #12 of the ACUAC and ACUHP Working Group TP Term Sheet.
Therefore, DOE is proposing to adopt these provisions of the AHRI 1340-
202X Draft for determining IVEC and IVHE.
d. Default Fan Power and Maximum Pressure Drop for Coil-Only Systems
DOE's current test procedure for CUACs and CUHPs references ANSI/
AHRI 340/360-2007, and section 6.1 of that test standard specifies
default fan power and corresponding capacity adjustment for ACUACs,
ACUHPs, ECUACs, and WCUACs with a coil-only configuration (i.e.,
without an integral indoor fan). Specifically, ANSI/AHRI 340/360-2007
requires that an indoor fan power of 365 Watts (W) per 1,000 standard
cubic feet per minute (scfm) be added to power input for coil-only
units and that the corresponding heat addition (i.e., 1,250 Btu/h per
1,000 scfm) be subtracted from measured cooling capacity (and added to
measured heating capacity), regardless of capacity of the unit under
test and regardless of full or part-load test conditions. In the July
2017 TP RFI, DOE requested comment on the prevalence of ACUACs, ACUHPs,
ECUACs, and WCUACs that are sold in coil-only configurations and
requested data on the typical efficiency or typical power use and
airflow of fans used with coil-only ACUACs, ACUHPs, WCUACs, and ECUACs
in field installations. 82 FR 34427, 34440 (July 25, 2017).
In response, Lennox and AHRI stated that the market for coil-only
ACUACs and ACUHPs is very small and that less than 1 percent of the
approximately 9,000 models listed in the AHRI directory are coil-only
models. In addition, Lennox and AHRI stated their expectation that the
coil-only configuration will become even less common or disappear from
the market by 2023 when new energy conservation standards become
effective. (Lennox, EERE-2017-BT-TP-0018-0008 at p. 3; AHRI, EERE-2017-
BT-TP-0018-0011 at pp. 23-24) Lennox recommended maintaining the
current default fan power because the market for these configurations
is very small and stated that the effect of any change in default fan
power associated with the difference in typical energy use would be de
minimis. (Lennox, EERE-2017-BT-TP-0018-0008 at p. 3)
Section 6.1.1.6 of AHRI 340/360-2022 has the same requirement as
ANSI/AHRI 340/360-2007 regarding default fan power and capacity
adjustment of coil-only systems. Additionally, both section 6.1.3.2(d)
of ANSI/AHRI 340/360-2007 and section 6.1.3.3.4 of AHRI 340/360-2022
specify that for coil-only systems, the pressure drop across the indoor
assembly shall not exceed 0.30 in H<INF>2</INF>O for the full-load
cooling test. If the measured pressure drop exceeds that value, then
the industry test standards specify that the indoor airflow rate be
reduced such that the measured pressure drop does not exceed the
specified maximum pressure drop.
The AHRI 1340-202X Draft includes different requirements for
testing coil-only units as compared to ANSI/AHRI 340/360-2007 and AHRI
340/360-2022. First, section 5.17.4 of the AHRI 1340-202X Draft
includes a higher maximum pressure drop across the indoor assembly of
1.0 in H<INF>2</INF>O when testing coil-only units, as compared to the
maximum pressure drop of 0.3 in H<INF>2</INF>O specified in ANSI/AHRI
340/360-2007 and AHRI 340/360-2022. Second, section 6.2.4.2 of the AHRI
1340-202X Draft includes higher default fan power values than specified
in ANSI/AHRI 340/360-2007 and AHRI 340/360-2022; these values were
updated to reflect the higher ESP requirements used for IVEC and IVHE.
Because the ACUAC and ACUHP Working Group TP Term Sheet and AHRI 1340-
202X Draft specify ESP requirements that vary by capacity bin, section
6.2.4.2 of the AHRI 1340-202X Draft specifies different default fan
power adders and capacity adjustments for each capacity bin, developed
based on fan power needed to overcome the ESP requirement for each bin.
Lastly, while ANSI/AHRI 340/360-2007 and AHRI 340/360-2022 specify
a single default fan power adder (and corresponding capacity
adjustment) to be used for all tests, the AHRI 1340-202X Draft includes
separate default fan power adders and capacity adjustments for full-
load tests and part-load tests (i.e., tests conducted at an airflow
lower than the full-load cooling airflow) to reflect that fan power
does not decrease linearly with airflow (i.e., reducing airflow in
part-load operation would reduce fan power in field operation by more
than would be calculated using a single power adder that is normalized
by airflow). These part-load fan power adders and capacity adjustments
were developed assuming a part-load airflow that is 67 percent of the
full-load airflow. The AHRI 1340-202X Draft does not specify what
values to use if the part-load airflow is higher than 67 percent of the
full-load airflow. In a test procedure final rule for CAC/HPs published
October 25, 2022, DOE adopted a part-load fan power adder and capacity
adjustment for coil-only systems based on 75 percent of the full-load
airflow, and specified that linear interpolation be used to determine
the default fan power coefficient between the part-load and full-load
default fan power coefficients when the specified part-load airflow is
between 75 and 100 percent of the full-load airflow. 87 FR 64550,
64558. DOE has tentatively concluded that similar linear interpolation
provisions would be appropriate for coil-only CUACs and CUHPs in the
case where the airflow specified by a manufacturer for a test is
between 67 and 100 percent of the full-load airflow. Therefore, DOE is
proposing to include similar provisions in appendix A1 that specify how
to calculate the default fan power coefficient and capacity adjustment
in such cases.
Consistent with the basis of part-load values in the AHRI 1340-202X
Draft on 67 percent of full-load cooling airflow, DOE is also proposing
to clarify that for tests in which the manufacturer-specified airflow
is less than the full-load cooling airflow, the target airflow for the
test must be the higher of: (1) the manufacturer-specified airflow for
the test; or (2) 67 percent of the airflow measured for the full-load
cooling test.
DOE tentatively concludes the changes to the coil-only test
procedure in the AHRI 1340-202X Draft represent industry consensus on
the most appropriate and representative way to test and determine IVEC
and IVHE of coil-only systems. Additionally, DOE has tentatively
concluded that provisions to address manufacturer-specified airflows
between 67 and 100 percent of full-load cooling airflow (via
interpolation between the specified full-load and part-load fan power
adders and capacity adjustments) would provide a representative means
to develop ratings for coil-only CUACs and CUHPs, consistent with the
CAC/HP test procedure at appendix M1. Lastly, these do not conflict
with any recommendations in the ACUAC and ACUHP Working Group TP Term
Sheet. DOE has tentatively concluded that these provisions provide a
representative method to test coil-only units that better aligns with
the test requirements for CUACs and CUHPs with integral fans specified
in the ACUAC and ACUHP Working Group TP Term Sheet and the AHRI 1340-
202X Draft. Therefore, DOE is proposing to reference the provisions for
testing coil-only units specified in sections 5.17.4 and 6.2.4.2 of the
AHRI 1340-202X Draft with additional instruction to use linear
interpolation for determining the fan power adder and capacity

[[Page 56418]]

adjustment for instances when manufacturers specify an airflow between
67 and 100 percent of full-load cooling airflow, and clarifying that
airflow for coil-only systems must not be lower than 67 percent of
full-load cooling airflow.
e. Component Power Measurement
Section E10 of AHRI 1340-202X Draft includes additional instruction
regarding how the total unit, indoor fan, controls, compressor,
condenser section, and crankcase heat power should be measured and
accounted for during a test. This includes details that were not
included in the ACUAC and ACUHP Working Group TP Term Sheet, as well as
updates to address issues such as unique model designs and power meter
precision that were identified after the term sheet was completed. For
example, although the ACUAC and ACUHP Working Group TP Term Sheet
specified that controls power be determined by subtracting all other
power measurements from the total unit power, sections E10.1 and E10.2
of AHRI 1340-202X Draft require that controls power be measured. This
is because controls power is a much smaller value than power consumed
by other components of a CUAC or CUHP and thus is more accurately
determined by measuring directly with a power meter of sufficient
precision. Section E10.2 of AHRI 1340-202X Draft also allows for
determination of compressor and condenser section power by measurement
together or by subtraction from total power (i.e., separate power
measurement of power consumed by the compressor and condenser section
is not required). These provisions address cases in which unique wiring
of certain models may make separate measurement of compressor and
condenser section power very difficult or impossible, in addition to
cases in which the laboratory does not have enough power meters to
measure all components separately. Section E10.3 also provides an
equation for calculating default value(s) for crankcase heater power to
address the case in which a manufacturer does not specify crankcase
heater wattage.\22\ DOE has tentatively concluded that these provisions
will provide more repeatable and representative test results and is
proposing to adopt them through reference to section E10 of the AHRI
1340-202X Draft.
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\22\ As discussed, Recommendation # 13 of the ACUAC and ACUHP
Working Group TP Term Sheet requires that manufacturers certify
crankcase heater wattage for each heater. DOE is not proposing
amendments to certification requirements in this rulemaking, and
will instead address certification requirements in a separate
rulemaking for certification, compliance, and enforcement.
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f. IVHE Equations
Section 6.3 of the AHRI 1340-202X Draft includes the following
changes regarding the heating metric equations that differ from the
provisions in appendix C of the ACUAC and ACUHP Working Group TP Term
Sheet.
1. Removal of the cut-out factor from certain equations

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