[Federal Register Volume 87, Number 205 (Tuesday, October 25, 2022)]
[Rules and Regulations]
[Pages 64550-64607]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-22257]
[[Page 64549]]
Vol. 87
Tuesday,
No. 205
October 25, 2022
Part II
Department of Energy
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10 CFR Parts 429 and 430
Energy Conservation Program: Test Procedure for Central Air
Conditioners and Heat Pumps; Final Rule
Federal Register / Vol. 87 , No. 205 / Tuesday, October 25, 2022 /
Rules and Regulations
[[Page 64550]]
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DEPARTMENT OF ENERGY
10 CFR Parts 429 and 430
[EERE-2021-BT-TP-0030]
RIN 1904-AF29
Energy Conservation Program: Test Procedure for Central Air
Conditioners and Heat Pumps
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Final rule.
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SUMMARY: The U.S. Department of Energy (``DOE'') is amending the test
procedures for central air conditioners and heat pumps that will be
required for certification of compliance with applicable energy
conservation standards starting January 1, 2023, to address a limited
number of specific issues, and making minor corrections to the current
test procedures that are required for certification of compliance with
applicable energy conservation standards prior to January 1, 2023. This
rulemaking does not satisfy the 7-year lookback requirement prescribed
by the Energy Policy and Conservation Act (``EPCA'').
DATES: The effective date of this rule is November 25, 2022. The final
rule changes will be mandatory for product testing starting April 24,
2023. The incorporation by reference of a certain publication listed in
the rule was approved by the Director of the Federal Register on
February 6, 2017.
ADDRESSES: The docket, which includes Federal Register notices, public
meeting attendee lists and transcripts, comments, and other supporting
documents/materials, is available for review at www.regulations.gov.
All documents in the docket are listed in the www.regulations.gov
index. However, not all documents listed in the index may be publicly
available, such as those containing information that is exempt from
public disclosure.
A link to the docket web page can be found at www.regulations.gov/docket/EERE-2021-BT-TP-0030 The docket web page contains instructions
on how to access all documents, including public comments, in the
docket.
For further information on how to review the docket contact the
Appliance and Equipment Standards Program staff at (202) 287-1445 or by
email: [email protected].
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: [email protected].
Mr. Pete Cochran, U.S. Department of Energy, Office of the General
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121.
Telephone: (202) 586-9496. Email: [email protected].
SUPPLEMENTARY INFORMATION: DOE maintains the following previously
approved incorporation by reference in part 430:
ANSI/ASHRAE Standard 37-2009, Methods of Testing for Rating
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment,
ANSI approved June 25, 2009;
Copies of ANSI/ASHRAE 37-2009, can be purchased from
www.ashrae.org/resources--publications.
For a further discussion of this standard, see section IV.M of this
document.
Table of Contents
I. Authority and Background
A. Authority
B. Background
II. Synopsis of the Final Rule
III. Discussion
A. Scope of Applicability
B. Requests for Future Test Procedure Revisions
C. Topics Arising From Test Procedure Waivers
1. Fan Power at Reduced Airflows for Coil-Only Systems
2. Variable-Speed Coil-Only Test Procedure
3. Space-constrained Coil-Only CAC Ratings
D. Other Test Procedure Revisions
1. Air Volume Rate Changing With Outdoor Conditions
2. Wet Bulb Temperature for H4 5 [deg]F Heating Tests
3. Hierarchy of Manufacturer Installation Instructions
4. Adjusting Airflow Measurement Apparatus To Achieve Desired
SCFM at Part-Load Conditions
5. Revision of Equations Representing Full-Speed Variable-Speed
Heat Pump Operation at and Above 45 [deg]F Ambient Temperature
6. Calculations for Triple-Capacity Northern Heat Pumps
7. Heating Nominal Air Volume Rate for Variable-Speed Heat Pumps
8. Clarifications for HSPF2 Calculation
9. Distinguishing Central Air Conditioners and Heat Pumps From
Commercial Equipment
10. Additional Test Procedure Revisions
E. Other Revisions Regarding Representations
1. Required Represented Values for Models Certified Compliant
With Regional Standards
F. Test Procedure Costs and Impact
G. Compliance Date and Waivers
H. Requests for Standards Relief
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 12866 and 13563
B. Review Under the Regulatory Flexibility Act
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 Material Incorporated by Reference
N. Congressional Notification
V. Approval of the Office of the Secretary
I. Authority and Background
Central air conditioners (``CACs'') and central air conditioning
heat pumps (``HPs'') (collectively, ``CAC/HPs'') are included in the
list of ``covered products'' for which DOE is authorized to establish
and amend energy conservation standards and test procedures (42 U.S.C.
6292(a)(3)) DOE's energy conservation standards and test procedures for
CAC/HPs are currently prescribed at title 10 of the Code of Federal
Regulations (``CFR''), part 430, Sec. 430.32(c), and 10 CFR part 430,
subpart B, appendices M (``appendix M'') and M1 (``appendix M1''). The
following sections discuss DOE's authority to establish test procedures
for CAC/HPs and relevant background information regarding DOE's
consideration of test procedures for this product.
A. Authority
The Energy Policy and Conservation Act, as amended (``EPCA''),\1\
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 B \2\ of EPCA established the Energy Conservation
Program for Consumer Products Other Than Automobiles, which sets forth
a variety of provisions designed to improve energy efficiency. These
[[Page 64551]]
products include CAC/HPs,\3\ the subject of this document. (42 U.S.C.
6292(a)(3))
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\1\ 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).
\2\ For editorial reasons, upon codification in the U.S. Code,
Part B was redesignated Part A.
\3\ This rulemaking uses the term ``CAC/HP'' to refer
specifically to central air conditioners (which include heat pumps)
as defined by EPCA. (42 U.S.C. 6291(21))
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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 specifically include definitions (42 U.S.C. 6291),
test procedures (42 U.S.C. 6293), labeling provisions (42 U.S.C. 6294),
energy conservation standards (42 U.S.C. 6295), and the authority to
require information and reports from manufacturers (42 U.S.C. 6296).
The Federal testing requirements consist of test procedures that
manufacturers of covered products must use as the basis for: (1)
certifying to DOE that their products comply with the applicable energy
conservation standards adopted pursuant to EPCA (42 U.S.C. 6295(s)),
and (2) making representations about the efficiency of those consumer
products (42 U.S.C. 6293(c)). Similarly, DOE must use these test
procedures to determine whether the products comply with relevant
standards promulgated under EPCA. (42 U.S.C. 6295(s))
Federal energy efficiency requirements for covered products
established under EPCA generally supersede State laws and regulations
concerning energy conservation testing, labeling, and standards. (42
U.S.C. 6297) DOE may, however, grant waivers of Federal preemption for
particular State laws or regulations, in accordance with the procedures
and other provisions of EPCA. (42 U.S.C. 6297(d))
Under 42 U.S.C. 6293, EPCA sets forth the criteria and procedures
DOE must follow when prescribing or amending test procedures for
covered products. EPCA requires that any test procedures prescribed or
amended under this section be reasonably designed to produce test
results which measure energy efficiency, energy use or estimated annual
operating cost of a covered product during a representative average use
cycle or period of use and not be unduly burdensome to conduct. (42
U.S.C. 6293(b)(3))
If the Secretary determines, on her own behalf or in response to a
petition by any interested person, that a test procedure should be
prescribed or amended, the Secretary shall promptly publish in the
Federal Register proposed test procedures and afford interested persons
an opportunity to present oral and written data, views, and arguments
with respect to such procedures. (42 U.S.C. 6293(b)(2)) The comment
period on a proposed rule to amend a test procedure shall be at least
60 days and may not exceed 270 days. Id. In prescribing or amending a
test procedure, the Secretary shall take into account such information
as the Secretary determines relevant to such procedure, including
technological developments relating to energy use or energy efficiency
of the type (or class) of covered products involved. Id.
DOE's regulations at 10 CFR 430.27 provide that any interested
person may seek a waiver from the test procedure requirements if
certain conditions are met. A waiver requires manufacturers to use an
alternate test procedure in situations in which the DOE test procedure
cannot be used to test the product or equipment, or use of the DOE test
procedure would generate unrepresentative results. 10 CFR 430.27(a)(1).
DOE's regulations at 10 CFR 430.27(l) require that as soon as
practicable after the granting of any waiver, DOE will publish in the
Federal Register a notice of proposed rulemaking (``NOPR'') to amend
its regulations so as to eliminate any need for the continuation of
such waiver. As soon thereafter as practicable, DOE will publish in the
Federal Register a final rule. 10 CFR 430.27(l).
DOE is publishing this final rule for the limited purpose of
addressing its obligations under the waiver process regulations at 10
CFR 430.27 and to incorporate additional corrections and improvements.
B. Background
As discussed, DOE's existing test procedures for CAC/HPs appear at
appendices M and M1 (both titled ``Uniform Test Method for Measuring
the Energy Consumption of Central Air Conditioners and Heat Pumps'').
On January 5, 2017, DOE published a final rule regarding the
Federal test procedure (``TP'') for CAC/HPs. 82 FR 1426 (``January 2017
CAC TP Final Rule''). The January 2017 CAC TP Final Rule amended
appendix M and established appendix M1, use of which is required
beginning January 1, 2023, for any representations, including
compliance certifications, made with respect to the energy use or
efficiency of CAC/HPs. Id. Appendix M provides for the measurement of
the cooling and heating performance of CAC/HPs using the seasonal
energy efficiency ratio (``SEER'') metric and heating seasonal
performance factor (``HSPF'') metric, respectively. Appendix M1
specifies a revised SEER metric (i.e., SEER2) and a revised HSPF metric
(``HSPF2'').
Since the publication of the January 2017 CAC TP Final Rule, DOE
has granted various petitions for waiver and interim waiver from
certain provisions of appendix M and/or M1.\4\ Additionally, DOE is
aware of testing conducted per both appendices M (via Compliance,
Certification and Enforcement (``CCE'') testing and other verification
programs) and M1 (via investigative testing to support development of
the 2023 energy efficiency standards). Through these efforts, DOE has
been made aware of several items for which test procedure amendments
are warranted in order to improve clarity or to reduce burden. In each
of these cases, DOE has determined that the amendments would have no or
negligible impact on ratings and thus do not require amendment of the
energy conservation standards per 42 U.S.C. 6293(e). These amendments
are described in section III.D of this final rule. Further, on May 8,
2019, AHRI submitted a comment responding to the notice of proposed
rulemaking to revise and adopt procedures, interpretations, and
policies for consideration of new or revised energy conservation
standards (2020 Process Rule NOPR, 84 FR 3910, Feb. 13, 2019) The
comment included as Exhibit 2 a ``List of Errors Found in both appendix
M and appendix M1'' (``AHRI Exhibit 2,'' EERE-2017-BT-STD-0062-0117 at
pp. 23-24). Many of the errors pointed out by AHRI regard typographical
errors in appendices M and M1. These issues are addressed in various
places of this final rule, including footnotes describing amendments to
correct section references, nomenclature, etc. that did not warrant
standalone discussion sections.
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\4\ Waivers granted to GD Midea Heating and Ventilating
Equipment Co., Ltd. (83 FR 56065), Johnson Controls, Inc. (83 FR
12735 and 84 FR 52489), and TCL Air Conditioner (Zhongshan) Co.,
Ltd. (84 FR 11941), interim waivers granted to National Comfort
Products, Inc. (83 FR 24754), Aerosys Inc. (83 FR 24762), LG
Electronics U.S.A., Inc. (85 FR 40272), and Goodman Manufacturing
Company, L.P. (86 FR 40534).
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On March 24, 2022, DOE published a notice of proposed rulemaking
regarding the Federal test procedure for CAC/HPs. 87 FR 16830 (``March
2022 CAC TP NOPR''). The March 2022 CAC TP NOPR proposed changes to
improve the functionality of appendix M1 to address the issues
identified in test procedure waivers, improve representativeness and
correct typographical issues raised by commenters. Id. DOE held a
public meeting related to the NOPR on April
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18, 2022 (hereafter the ``2022 CAC TP NOPR Public Meeting'').
DOE received comments in response to the March 2022 CAC TP NOPR
from the interested parties listed in Table I-1.
Table I-1--List of Commenters With Written Submissions in Response to the March 2022 CAC TP NOPR
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Reference in this final Comment No. in
Commenter(s) rule the docket Commenter type
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Air-Conditioning, Heating, & AHRI...................... 25 Trade Association.
Refrigeration Institute.
Appliance Standards Awareness Project Joint Advocates........... 18 Efficiency organizations.
(ASAP), American Council for an Energy-
Efficient Economy (ACEEE).
Pacific Gas and Electric Company, San CA IOUs................... 20 Efficiency organization.
Diego Gas and Electric, Southern
California Edison--collectively
California Investor Owned Utilities.
Carrier Global Corporation.............. Carrier................... 15 Manufacturer.
Daikin Comfort Technologies Daikin.................... 24 Manufacturer.
Manufacturing Company, L.P.
Emerson Climate Technologies, Inc....... Emerson................... 14 Manufacturer.
Leaders Building of America............. LBA....................... 3 Trade Association.
Lennox International Inc................ Lennox.................... 19 Manufacturer.
National Comfort Products, Inc.......... NCP....................... 16 Manufacturer.
Northwest Energy Efficiency Alliance.... NEEA...................... 23 Alliance of Efficiency
Organizations.
Nortek Global HVAC (NGH)................ Nortek.................... 13 Manufacturer.
New York State Energy Research and NYSERDA................... 17 Efficiency organization.
Development Authority.
Rheem Sales Company..................... Rheem..................... 21 Manufacturer.
Samsung HVAC............................ Samsung................... 22 Manufacturer.
Trane Technologies...................... Trane..................... 10 Manufacturer.
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A parenthetical reference at the end of a comment quotation or
paraphrase provides the location of the item in the public record.\5\
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\5\ The parenthetical reference provides a reference for
information located in the docket of DOE's rulemaking to develop
test procedures for central air conditioners and heat pumps (Docket
No. EERE-2021-BT-TP-0030, which is maintained at
www.regulations.gov). The references are arranged as follows:
(commenter name, comment docket ID number, page of that document).
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The CA IOUs, Carrier, Daikin, Emerson, Joint Advocates, Lennox,
NEEA, Nortek, NYSERDA, and Rheem commented that they largely supported
DOE's efforts in amending the existing test procedure in appendix M1.
(CA IOUs, No. 20 at p. 3, Carrier, No. 20 at p. 1, Daikin, No. 24 at p.
1, Emerson, No. 14 at p. 1, Joint Advocates, No. 18 at p. 1, Lennox,
No. 19 at p. 1, NEEA, No. 23 at p. 1, Nortek, No. 13 at p. 1, NYSERDA,
No. 17 at p. 1, Rheem, No. 21 at p. 1) Emerson requested that DOE
publish the revised test procedure as soon as reasonably possible, so
that manufacturers will have time to comply with the compliance date of
January 1, 2023. (Emerson, No. 14 at p. 3) Nortek also requested that
DOE publish the final rule soon, so that they can have certainty with
the revised test procedure, in order to serve the CAC/HP market
efficiently. (Nortek, No. 13 at p. 3)
II. Synopsis of the Final Rule
In this final rule, DOE is updating appendix M1 to subpart B of
part 430, ``Uniform Test Method for Measuring the Energy Consumption of
Central Air Conditioners and Heat Pumps.'' DOE has identified certain
provisions of appendix M1 that may benefit from additional detail and/
or instruction. The updates are as follows:
(1) Adjusting the default fan power for two-stage coil-only systems
when testing at low stage with reduced air volume rate to be more
representative of fan input power trends as air volume rate reduces;
(2) Defining ``variable-speed communicating coil-only central air
conditioner or heat pump'' and ``variable-speed non-communicating coil-
only central air conditioner or heat pump'' and establishing procedures
specific for testing such systems;
(3) Allowing the adjustment of the air volume rate as a function of
outdoor air temperature during testing for blower coil systems with
either multiple-speed or variable-speed indoor fans and with a control
system capable of adjusting air volume rate as function of outdoor air
temperature;
(4) Adjusting the maximum wet bulb temperature from 3 [deg]F to 4
[deg]F for the H4 test condition;
(5) Specifying in section 2(B) of appendix M1, that the
instructions presented in the labels attached to the unit take
precedence over the installation manuals printed and shipped with a
product;
(6) Specifying in sections 3.1.4.1.1, 3.1.4.1.2, and 3.1.4.4.3 of
appendix M1 that the airflow measurement apparatus fan must be adjusted
if necessary to maintain the same air volume rate for different test
conditions for systems not including multiple-speed or variable-speed
indoor fans with control system capability to adjust air volume rate as
function of operating conditions such as outdoor air temperature; and
(7) Revising the equations representing full-capacity operation of
variable-speed heat pumps at and above 45 [deg]F ambient temperature to
be consistent with the intent for nominal capacity operation.
Additionally, in this final rule, DOE is updating 10 CFR part 429,
``Certification, Compliance, and Enforcement for Consumer Products and
Commercial and Industrial Equipment.'' DOE has identified certain
provisions of part 429 that may benefit from additional detail and/or
instruction. The proposed updates are as follows:
(1) Clarifying the language for required represented values for
single-stage and two-stage coil-only CACs; and
(2) Providing additional direction regarding the regional standard
requirements in part 429.
The adopted amendments are summarized in Table II-1 compared to the
test procedure provision prior to the amendment, as well as the reason
for the adopted change. Additional proposed incidental changes are
summarized in Table III-4, Table III-5 and Table III-6 in section
III.D.10 of this document.
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Table II-1--Summary of Changes in the Amended Test Procedure
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DOE test procedure prior to amendment Amended test procedure Attribution
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Calculate indoor fan power of two-stage Calculate indoor fan power of two-stage Improve
coil-only CACs and HPs using constant coil-only CACs and HPs for reduced air representativeness.
default fan power values that do not vary volume rate tests using new default fan
with air volume rate (441W/1000 scfm for power values air volume rate (335 W/1000
most two-stage coil-only CACs and HPs and scfm for most two-stage coil-only CACs
406 W/1000 scfm for mobile-home and space- and HPs and 308 W/1000 scfm for mobile-
constrained CACs and HPs). home and space-constrained CACs and HPs).
Use linear interpolation to determine fan
performance at intermediate airflow rates
between 75 percent and 100 percent of
full-load air volume rate.
No test procedure provisions for variable- Test procedures and requirements Incorporate test
speed, coil-only CACs and HPs. established for variable-speed coil-only procedures contained in
systems, include new definitions for test procedure waivers.
``variable-speed communicating coil-only
central air conditioner or heat pump''
and ``variable-speed non-communicating
coil-only central air conditioner or heat
pump,'' for which the newly established
test procedures have more flexibility.
Appendix M1 currently does not explicitly For blower coil systems with multiple- Improve
allow for variation of air volume rate as speed or variable-speed indoor fans and representativeness for
outdoor temperature changes when testing the control system capability to adjust certain models.
blower coil systems. air volume rate as a function of outdoor
air temperature, allow such air volume
rate variation during testing.
Appendix M1 contains provisions for Amend the wet bulb test condition for the Reduce test burden by
conducting an optional H4 heating test at H4 test to be 4 [deg]F maximum instead of reducing the time
a 5 [deg]F outdoor ambient dry-bulb the current condition of 3 [deg]F needed to remove
temperature and, at a maximum, a 3 [deg]F maximum. sufficient moisture to
outdoor wet-bulb temperature. achieve the wet bulb
requirement.
Clarification regarding which form of Add direction to prioritize the Improve
installation instructions to use, if instructions presented in the label representativeness and
multiple forms are provided, only for attached to the unit over the repeatability.
variable refrigerant flow (VRF) installation instructions shipped with
multisplit systems. the unit for all CAC/HP products.
Appendix M1 currently is not clear about Add specific instruction to adjust the Improve
how to achieve the same air volume rate airflow measurement apparatus fan but not representativeness and
for different test conditions. the fan of the unit under test to achieve repeatability.
the same air volume rate for different
tests.
The equations for full-capacity operation Revise the equations for full-capacity Improve
for variable-speed heat pumps at and operation at and above 45 [deg]F to be representativeness.
above 45 [deg]F ambient temperature are more consistent with compressor speed
based on operating in this range with a used in normal operation for this
compressor speed the same as its temperature range, represented by the
operation in 17 [deg]F ambient nominal heating test condition, H1N.
temperature.
10 CFR part 429 provides requirements Reinforce the language explaining regional Improve clarity.
regarding regional CAC/HP efficiency requirements.
standards.
10 CFR 429.16(a)(1) provides requirements Modify the instructions in that section to Improve repeatability.
for represented values of single-stage improve clarity without changing meaning.
and two-stage coil-only CACs that can
lead to different interpretation.
10 CFR 430.2 defines central air Add exclusions for additional commercial Improved
conditioner, excluding two commercial package air-conditioning and heating representativeness.
package air-conditioning and heating categories that justifiably are not
categories--packaged terminal air central air conditioners.
conditioners and packaged terminal heat
pumps.
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As mentioned previously, DOE is also fixing typographical errors in
appendices M and M1 that were raised by AHRI. (``AHRI Exhibit 2,''
EERE-2017-BT-STD-0062-0117 at pp. 23-24) DOE is addressing these issues
in this rulemaking.
Under 42 U.S.C. 6293(e)(1), DOE is required to determine whether an
amended test procedure will alter the measured energy use of any
covered product. If an amended test procedure does alter measured
energy use, DOE is required to make a corresponding adjustment to the
applicable energy conservation standard to ensure that minimally
compliant covered products remain compliant. (42 U.S.C. 6293(e)(2)) DOE
has determined that the amendments described in section III of this
final rule would not alter the measured efficiency of CAC/HPs that are
rated using the test procedure that is currently required for testing,
i.e., appendix M. The revisions applicable for appendix M simply fix
errors within the current test procedure. With respect to appendix M1,
many of the amendments clarify test procedures rather than making
changes that would affect the measurements. Variable-speed coil-only
systems are not addressed currently in the test procedure, so this
final rule establishes a method of test for those products. For two-
stage coil-only systems, DOE is amending the default fan power
coefficients and default fan heat coefficients to be more
representative, as further described in section III.C.1 of this
document, which DOE believes will slightly improve the measured
efficiency of these combinations as compared to their current
representative values. Given that two-stage combinations are not
representative of minimally compliant combinations, DOE has determined
that this amendment would not require an
[[Page 64554]]
adjustment to the energy conservation standard for central air
conditioners and heat pumps to ensure that minimally compliant central
air conditioners and heat pumps would remain compliant. Additionally,
DOE has determined that the amendments would not increase the cost of
testing. Discussion of DOE's actions are addressed in detail in section
III of this final rule.
The effective date for the amended test procedures adopted in this
final rule is 30 days after publication of this document in the Federal
Register. Representations of energy use or energy efficiency must be
based on testing in accordance with the amended test procedures
beginning 180 days after the publication of this final rule.
III. Discussion
A. Scope of Applicability
DOE is amending the test procedures at appendix M1 for CAC/HP and
implementing a few minor clerical revisions to the test procedures at
appendix M. A ``central air conditioner or central air conditioner heat
pump'' is defined as a product, other than a packaged terminal air
conditioner or packaged terminal heat pump, which is powered by single
phase electric current, air cooled, rated below 65,000 British thermal
units per hour (``Btu/h''), not contained within the same cabinet as a
furnace, the rated capacity of which is above 225,000 Btu/h, and is a
heat pump or a cooling unit only. A central air conditioner or central
air conditioning heat pump may consist of: A single-package unit; an
outdoor unit and one or more indoor units; an indoor unit only; or an
outdoor unit with no match. In the case of an indoor unit only or an
outdoor unit with no match, the unit must be tested and rated as a
system (combination of both an indoor and an outdoor unit). 10 CFR
430.2.
Appendices M and M1 apply to the following CACs/HPs:
Split-system air conditioners, including single-split,
multi-head mini-split, multi-split (including VRF), and multi-circuit
systems;
Split-system heat pumps, including single-split, multi-
head mini-split, multi-split (including VRF), and multi-circuit
systems;
Single-package air conditioners;
Single-package heat pumps;
Small-duct, high-velocity systems (including VRF);
Space-constrained products--air conditioners; and
Space-constrained products--heat pumps.
See Section 1.1 of appendices M and M1.
DOE is not proposing to change the scope of CACs/HPs covered by
appendices M and M1.
B. Requests for Future Test Procedure Revisions
DOE has considered whether the current test procedures for
variable-speed systems generally give manufacturers too much
flexibility in specifying fixed settings of the compressor and indoor
fan for testing without requiring the selected settings to be
demonstrated using native control testing. DOE is aware that there is
ongoing work addressing questions about whether the current DOE test
procedure for variable-speed systems is fully representative of native
control operation.\6\ However, DOE has initiated this rulemaking not as
a comprehensive revision that will satisfy the 7-year lookback
requirements (see 42 U.S.C. 6293(b)(1)(A)), but instead as an action
that will address a focused group of known issues, including those that
have been raised through the test procedure waiver process. Thus, DOE
limited its amendments addressing potential concerns about variable-
speed systems to coil-only systems, for which there are clear
differences in system controls architecture that impact the performance
of these systems in the field, particularly when using non-
communicating controls. However, DOE may more comprehensively address
these issues for all variable-speed systems in a future rulemaking.
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\6\ E.g., The German energy regulatory body, Bunderstalt
f[uuml]r Materialforschung und-Pr[uuml]fung (``BAM''), has developed
a dynamic load compensation method, to be used as an alternative to
EN 14825:2016 ``Air conditioners, liquid chilling packages and heat
pumps, with electrically driven compressors, for space heating and
cooling. Testing and rating at part load conditions and calculation
of seasonal performance''. Additionally, the Canadian Standards
Association (``CSA'') has published the first draft edition of
CSA:EXP07:19 ``Load-based and climate-specific testing and rating
procedures for heat pumps and air conditioners'' (``EXP07'').
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The CA IOUs, Joint Advocates, NEEA, and NYSERDA all encouraged DOE
to review ways to improve the representativeness of the test procedures
for CAC/HP in a future rulemaking under DOE's 7-year lookback
authority. Specifically, the CA IOUs, Joint Advocates, and NEEA all
requested that DOE explore approaches that would capture the
performance of variable-speed and multi-stage systems operating under
native controls rather than under fixed compressor and fan speed
controls. (CA IOUs, No.20 at pp.2-3; Joint Advocates, No.18 at p.1;
NEEA, No.23 at p.1)
The CA IOUs contended that the current test procedure does not
fully reflect energy use during the shoulder-season hours when outdoor
temperatures are typically between 55 [deg]F and 64 [deg]F and the
equipment is likely in fan-only mode (i.e., the compressor is not
running). (CA IOUs, No.20 at pp.2-3) DOE acknowledges the CA IOUs'
comment that shoulder-season fan energy consumption is not captured by
either the SEER/SEER2 or HSPF/HSPF2 metrics, which are constructed to
represent the cooling season efficiency and heating season efficiency,
respectively. However, as previously mentioned, DOE is only planning to
address a focused group of known issues in this rulemaking and will
evaluate and addresses a broader set of changes in a future rulemaking.
The CA IOUs acknowledged this point in their comment, by suggesting
that DOE consider fan-only energy use during the shoulder-season in a
subsequent review of the CAC/HP test procedure. Id. Therefore, DOE will
not adopt any amendments in this rulemaking related to shoulder-season
energy consumption, as suggested by the CA IOUs.
The CA IOUs also suggested that DOE consider approaches in a future
rulemaking to incorporate the power consumption of auxiliary components
like fans and crankcase heaters operating when the compressor is off.
(CA IOUs, No.20 at pp.2-3) DOE notes that there are already test
procedures and energy conservation standards governing the allowable
off-mode power consumption for CACs and HPs, which encapsulates the
off-mode and standby power consumed by auxiliary components such as
crankcase heaters as suggested by the CA IOUs. These test procedures
are enumerated in section 4.3 of appendices M and M1, and standards are
enumerated at 10 CFR 430.32(c)(4).
The CA IOUs further requested that DOE amend the definition of
``variable-speed compressor systems'' to incorporate CAC/HPs with at
least three compressor capacity stages that do not meet the definitions
of VRF or triple-capacity northern heat pumps. Specifically, the CA
IOUs suggested the following definition (additions in italics):
Variable-speed compressor system means ``a central air conditioner
or heat pump that has a compressor that uses a variable-speed drive to
vary the compressor speed to achieve variable capacities or a
compressor with at least three compressor capacity stages not including
triple-capacity northern heat pumps.'' (CA IOUs, No.20 at p.2)
Section 1.2 of appendix M1 defines ``variable-speed compressor
systems'' as those CAC/HPs that have ``a compressor
[[Page 64555]]
that uses a variable-speed drive to vary the compressor speed to
achieve variable capacities.'' The definition for ``variable
refrigerant flow (VRF) systems'' includes the language ``multi-split
system with at least three compressor capacity stages, distributing
refrigerant through a piping network to multiple indoor blower coil
units.'' The definition for ``triple-capacity, northern heat pump'' in
appendix M1 includes ``a heat pump that provides two stages of cooling
and three stages of heating.'' DOE agrees with the CA IOUs' assertion
that as currently structured, the definitions in appendix M1 do not
explicitly clarify coverage for the specific case of CAC/HP systems
having three or more stages (but without a variable-speed drive), do
not include multiple indoor units (which would meet the definition for
VRF), and are not heat pumps that include two cooling stages and three
heating stages (which would meet the definition for triple-capacity
northern heat pump). However, DOE is not aware of, nor did the CA IOUs
identify, the existence of such systems. Also, as previously mentioned,
DOE is only planning to address a focused group of known issues in this
rulemaking and will evaluate and addresses a broader set of changes in
future rulemaking. Therefore, DOE will not adopt the revised definition
of ``variable-speed compressor systems,'' as suggested by the CA IOUs
in this rulemaking. DOE may consider changes to the definition of
``variable-speed compressor system'' in a future rulemaking, if
provided additional evidence of systems existing that meet the criteria
of the hypothetical system described by the CA IOUs.
NEEA and the Joint Advocates recommended that DOE adopt a test
procedure that evaluates performance under loads that respond to the
heat pump's internal firmware. (NEEA, No.23 at p.1; Joint Advocates,
No.18 at pp. 3-4) NEEA provided data to support their claim that
seasonal efficiency performance is highly dependent on the installed
firmware of the system. Id. at pp.3-4. NEEA compiled this information
in a report \7\ that was also cited by the Joint Advocates in their
comment. (Joint Advocates, No.18 at p.4)
---------------------------------------------------------------------------
\7\ NEEA report ``Heat Pump and Air Conditioner Efficiency
Ratings: Why Metrics Matter'' available online at: https://neea.org/resources/heat-pump-and-air-conditioner-efficiency-ratings-why-metrics-matter.
---------------------------------------------------------------------------
NEEA also requested that DOE adopt a load-based test procedure with
the tested system operating under native controls. (NEEA, No.23 at p.2)
NEEA again provided data concerning the representativeness of the
existing DOE test procedure as compared to field data. NEEA cited
several ongoing projects related to evaluation of load-based testing of
CAC/HP and recommended that DOE leverage this work as a part of the
next CAC/HP test procedure rulemaking. Id. at pp.5-7. NEEA additionally
requested that DOE consider increasing the amount of data reported for
heat pumps operating at pert-load heating conditions, specifically
advocating for required reporting of COP for low-compressor-stage tests
at 67 [deg]F and 47 [deg]F. Id. at p.7.
NYSERDA encouraged DOE to start immediately on foundational work
needed to improve the standard and test procedure to better account for
equipment performance in cold climates. NYSERDA requested that DOE make
the H4, H42, or H43 heating tests mandatory in
order to produce more representative ratings that account for system
performance at 5 [deg]F. NYSERDA also requested that DOE explore how to
test and report relative capacity maintenance at temperatures lower
than the heating mode test temperatures that are used to determine
nominal capacity and suggested that DOE prescribe performance
requirements of low-temperature capacity maintenance for products
advertised as cold-climate heat pumps.\8\ Further, NYSERDA requested
that DOE evaluate how a variety of sizing approaches could be
incorporated into the test procedure. NYSERDA highlighted that DOE has
previously established that the sizing assumptions inherent in the DOE
test procedure are based on cooling capacity and provided an example of
a sizing and selection guide that emphasizes heating function.\9\
NYSERDA ultimately acknowledged that DOE is addressing a more limited
set of issues in this rulemaking and suggested that if their comments
could not be considered now, they should be considered applicable for
the next test procedure update for CACs or other HVAC equipment, as
appropriate. (NYSERDA, No.17 at pp.2-3)
---------------------------------------------------------------------------
\8\ NYSERDA cited the EPA's Energy Star Version 6.1 CAC/HP
specification, which prescribes a heating capacity maintenance of
70% at 5 [deg]F relative to 47 [deg]F for cold-climate heat pumps.
The Energy Star specification can be found online at: https://www.energystar.gov/sites/default/files/ENERGY%20STAR%20Central%20Air%20Conditioner%20and%20Heat%20Pump%20Version%206.1%20Final%20Specification.pdf.
\9\ NYSERDA identified NEEP's ASHP sizing and selection guide,
available online at: https://neep.org/sites/default/files/resources/ASHP%20Sizing%20%26%20Selecting%20-%208x11_edits.pdf.
---------------------------------------------------------------------------
In summary, DOE received a variety of comments that requested
changes to the CAC test procedure beyond the limited scope of proposals
in the March 2022 CAC TP NOPR. DOE received comments recommending
consideration of load-based testing methods, controls validation
(particularly for variable-speed systems), amended metrics, amended
definitions, and expansion of test methods to capture low-temperature
heating performance for heat pumps. As stated, DOE will consider these
comments when conducting the next rulemaking that includes a full
review of the CAC test procedure.
C. Topics Arising From Test Procedure Waivers
1. Fan Power at Reduced Airflows for Coil-Only Systems
a. Background
Coil-only air conditioners are matched split-systems consisting of
a condensing unit and indoor coil that are distributed in commerce
without an indoor blower or separate designated air mover. Such systems
installed in the field rely on a separately installed furnace or a
modular blower for indoor air movement. Because coil-only CAC/HPs do
not include their own indoor fan to circulate air, the DOE test
procedures prescribe equations that are used to calculate the assumed
(i.e., ``default'') power input and heat output of an average furnace
fan with which the test procedure assumes the indoor coil is pared in a
field installation. In each equation, the measured airflow rate (in
cubic feet per minute of standard air (``scfm'')) is multiplied by a
defined coefficient (expressed in Watts (``W'') per 1,000 scfm (``W/
1000 scfm'') for fan power, and British Thermal Units (``Btu'') per
hour (``Btu/h'') per 1000 scfm (``Btu/h/1000 scfm'') for fan heat),
hereafter referred to as the ``default fan power coefficient'' and
``default fan heat coefficient.'' The resulting fan power input value
is added to the electrical power consumption measured during testing.
The resulting fan heat output value is subtracted from the measured
cooling capacity of the CAC/HP for cooling mode tests and added to the
measured heating capacity for heating mode tests.
In appendix M1, separate fan power and fan heat equations are
provided for different types of coil-only systems (i.e., the equations
for mobile home or space-constrained are different than for
``conventional'' non-mobile home and non-space-constrained).\10\ 10 CFR
part
[[Page 64556]]
430, subpart B, appendix M1, see, e.g., section 3.3. For coil-only
units installed in mobile-homes and for space-constrained systems,
appendix M1 defines a default fan power coefficient of 406 W/1000scfm
and a default fan heat coefficient of 1,385 Btu/h/1000 scfm. See, e.g.,
appendix M1, section 3.3.d. For coil-only units installed in
conventional (i.e., non-mobile-home and non-space-constrained) systems,
appendix M1 defines a default fan power coefficient of 441 W/1000 scfm
and a default fan heat coefficient of 1,505 Btu/h/1000 scfm. See, e.g.,
appendix M1, section 3.3.e. In appendix M1, for both the default fan
power coefficient and default fan heat coefficient, the same
coefficient is used for both the full-load and part-load tests.
---------------------------------------------------------------------------
\10\ The different default fan power and default fan heat
coefficients for mobile-home and space-constrained systems as
compared to conventional systems reflect the lower duct pressure
drop expected for such systems in field operation--the lower values
are consistent with the lower external static pressure levels
required in testing of blower-coil systems intended for mobile home
and spaced-constrained applications (see Table 4 of appendix M1).
---------------------------------------------------------------------------
In the March 2022 CAC TP NOPR, DOE discussed a petition for waiver
and interim waiver filed by Nortek on September 7, 2021, that requested
an alternate test procedure that would define lower default fan power
and fan heat coefficients for the part-load tests, instead of applying
the same coefficients to both the full-load and part-load tests, as is
done in appendix M1. 87 FR 16830, 16834-16835; see Nortek, EERE-2021-
BT-WAV-0025, No. 1 at pp. 4-9. In response, DOE published a notice that
announced its receipt of the petition for waiver and denial of Nortek's
petition for an interim waiver. Id. See 86 FR 63357 (``Notification of
Petition for Waiver''). In the Notification of Petition for Waiver, DOE
noted that applying the modified default fan power coefficients and
default fan heat coefficients in appendix M1 to products such as those
that are the subject of Nortek's petition was determined to be
representative of the systems' performance and reflected the adoption
of the recommendations of a working group formed to negotiate a notice
of proposed rulemaking for energy conservation standards for CAC/HPs;
and that the modified coefficients were subject to public comment
during the 2016 test procedure rulemaking for CAC/HPs (``2016 CAC TP
Rulemaking''). Id. See 82 FR 1426, 1452. DOE also noted that Nortek
commented in support of the modified coefficients during the 2016 CAC
TP Rulemaking. Id.
In response to the issue raised by Nortek, DOE re-examined the
furnace fan electrical power consumption data collected for the furnace
fans rulemaking (see 79 FR 506, Jan. 3, 2014) that was used to develop
the default fan power coefficients and default fan heat coefficients
for coil-only products in appendix M1. DOE extended the prior analysis
to examine both full-load and part-load air volume rates.\11\ DOE
correlated the predicted power consumption with the predicted air
volume rate for each furnace fan to determine adjusted values of the
default fan power coefficients that may result in a more representative
estimate of fan power and fan heat at reduced airflow conditions,
compared to the coefficients currently defined in appendix M1. DOE's
analysis indicated that at a reduced air volume rate of 75 percent, the
average indoor fan power coefficient would be 360 W/1000 scfm for coil-
only CAC/HPs in a conventional (i.e., non-mobile-home and non-space-
constrained) installation. For mobile-home and space-constrained
systems, the average indoor fan power coefficient would be 331 W/1000
scfm.\12\ DOE also calculated the fan heat coefficients associated with
these power input levels. The average indoor fan heat coefficients
would be 1,228 Btu/hr/1000 scfm and 1,130 Btu/h/1000 scfm for
conventional (i.e., non-mobile-home and non-space-constrained) and
mobile-home/space-constrained installations, respectively. 78 FR 16830,
16834-16835.
---------------------------------------------------------------------------
\11\ To ensure consistency across analyses, DOE aggregated the
data by applying market weightings to each type and brand of furnace
model, using the same market shares that were used in the previous
analysis for the 2016 CAC TP Rulemaking.
\12\ For example, under DOE's proposed changes to appendix M1,
for a two-stage coil-only system in a conventional application that
has a cooling full-load air volume rate of 1640 scfm and a cooling
minimum (i.e., part-load) air volume rate of 1,230, the default fan
power at full load would be calculated as (441 W/1000scfm x 1640
scfm = 723 W); and default fan power at part-load would be
calculated as (360 W/1000scfm x 1230 scfm = 443 W).
---------------------------------------------------------------------------
The analysis conducted by DOE for the March 2022 CAC TP NOPR
resulted in higher default fan power coefficients and default fan heat
coefficients at the reduced 75 percent air volume rate than the values
presented in the Nortek waiver petition. DOE tentatively concluded that
its analysis is a more appropriate representation of average furnace
fan power consumption than the results presented by Nortek because (1)
DOE's analysis relied on empirical test results while Nortek's analysis
was theoretical, (2) DOE's analysis applied the same weighting factors
\13\ from the 2016 CAC TP Rulemaking to ensure consistency, and (3)
DOE's analysis considered constant-torque brushless-permanent-magnet
``X13'' motors while Nortek's analysis did not. DOE proposed to amend
the default fan power coefficients and default fan heat coefficients
for coil-only fan power when operating at reduced air volume rates to
reflect the results of its analysis. Id.
---------------------------------------------------------------------------
\13\ DOE's analysis included weighting based on market share by
brand, installations per cooling capacity range, and projected
shares in 2021 for different furnace fan motor types.
---------------------------------------------------------------------------
AHRI, Carrier, Emerson, the Joint Advocates, Lennox, Nortek, and
Rheem all supported DOE's proposal to reduce the default fan power and
fan heat coefficients for low-stage operation of coil-only
conventional, mobile-home and space-constrained CACs. (AHRI, No.25 at
p.3; Carrier, No.15 at p.2; Emerson, No.14 at p.1; Joint Advocates,
No.18 at p.1; Lennox, No.19 at p.2; Nortek, No.13 at p.1; Rheem, No.21
at p.1) Carrier, the Joint Advocates, and Lennox all stated that DOE's
proposal to include a lower default fan power coefficient at part-load
airflows would improve the representativeness of testing for two-stage
coil-only systems over the current approach in appendix M1. (Carrier,
No.15 at p.1; Joint Advocates, No.18 at p.1; Lennox, No.19 at p.2) Even
though there was general support for DOE's proposals, several comments
were received on the specific proposed values and the assumptions made
in order to calculate them. The following sections detail these
specific comments.
b. BPM Market Penetration
Despite supporting DOE's proposal to establish a second default fan
power coefficient representing low-stage operation, AHRI argued that
DOE's proposed part-load default fan power and heat coefficients were
still higher than they should be. (AHRI, No.25 at pp. 2-3) Carrier,
Daikin, Emerson, Lennox, Nortek, and Rheem all agreed with the AHRI
comment that the part-load default fan power and heat coefficients
should be lower than the proposed values. (Carrier, No.15 at p.2;
Daikin, No.24 at p.1; Emerson, No.14 at p.1; Lennox, No.19 at p.2;
Nortek, No.13 at pp.1-2; Rheem, No.21 at pp.1-2)
A key factor in AHRI's argument was that the actual market
saturation rate of furnace fans installed with higher-efficiency
brushless permanent magnet ``BPM'' \14\ fan motors is higher than
assumed in the analyses presented by DOE. (AHRI, No.25 at pp.2-3) DOE
first
[[Page 64557]]
presented its assumptions regarding relative prevalence of BPM motors
for furnace fans in a December 5, 2016, Technical Support Document
(``TSD'') used for the concurrent energy conservation standards
(``ECS'') rulemaking. EERE-2014-BT-STD-0048-0098 (``December 2016 CAC
ECS TSD''). In that document, DOE described its findings that in
2021,\15\ the estimated mix of blower types in existing furnaces would
be 77 percent permanent split capacitor (``PSC''), 15 percent constant-
speed BPM, and 9% constant-torque BPM. (EERE-2014-BT-STD-0048-0098,
page 7-16) DOE assumed the same proportion of furnace fan motor types
in its analysis for the March 2022 CAC TP NOPR.
---------------------------------------------------------------------------
\14\ In their comment, AHRI used the term ``electronically
commutated motor'' (ECM) to describe higher-efficiency motors
available in the furnace fans market. However, all instances in this
final rule have been changed to ``brushless permanent magnet'' (BPM)
which better describes the motor construction.
\15\ At the time the 2016 CAC ECS TSD was drafted, the proposed
compliance date for amended standards was Jan. 1, 2021--therefore
DOE forecasted the fan motor proportions in the anticipated year
that standards would come into effect. In the January 2017 direct
final rule regarding energy conservation standards (82 FR 1786,
January 6, 2017) (``January 2017 CAC ECS Direct Final Rule''),
however, the compliance date was delayed by two years to January 1,
2023. DOE did not provide estimates of assumed furnace fan motor
composition in the year 2023.
---------------------------------------------------------------------------
In order to support its claim that the market saturation rate of
BPM furnace fan motors was higher than the rate estimated by DOE, AHRI
cited the 2019 compliance date for efficiency standards for furnace
fans and stated that nearly all new furnaces shipped since 2019 have
exclusively used BPMs. (AHRI, No.25 at pp.2-3) AHRI also claimed that
the pending refrigerant change in the U.S. will require replacement of
R-410A systems in both indoor and outdoor units for CAC systems,
starting in 2025. AHRI asserted that due to these regulations,
consumers with older furnaces would be more likely to simultaneously
replace their furnaces at the same time as a whole-system CAC
replacement, leading to a wave of newly installed furnace fans using
BPM fan motors. Id. AHRI then forecasted the number of installed
furnaces and percent share of furnaces with BPM furnace fans using
DOE's estimates for equipment retirement Weibull curves, AHRI
historical shipments data,\16\ and 2015 Residential Energy Consumption
Survey (RECS) microdata.\17\ Ultimately, AHRI forecasted the
penetration of BPM furnace fan motors to reach 50 percent by 2025. Id.
NCP and Nortek both supported AHRI's analysis regarding the relative
prevalence of furnace fans having BPM motors, stating that the Fan
Energy Rating (FER) standards effectively obsoleted PSC motors in new
furnace fans in favors of BPM motors. (NCP, No.16 at pp.8-9; Nortek,
No.13 at p.2) NCP reiterated AHRI's claim that future refrigerant
regulations could increase the pace of furnace replacements and thus
accelerate the adoption of furnace fans with BPM motors. (NCP, No.16 at
p.8)
---------------------------------------------------------------------------
\16\ AHRI historical shipments estimates available online at:
https://ahrinet.org/resources/statistics/historical-data/furnaces-historical-data.
\17\ Residential Energy Consumption Survey data available online
at: https://www.eia.gov/consumption/residential/data/2015/.
---------------------------------------------------------------------------
To evaluate AHRI's claims about furnace fan BPM penetration rates,
DOE reconstructed AHRI's analysis using RECS microdata and engineering
assumptions about typical furnace lifetime and historical prevalence of
BPM fan motors in furnace fans. DOE estimated the annual inflows and
outflows (i.e., new sales and decommissioning at end-of-life) of BPM
furnace fan motors, using the assumption that all new furnace fan
motors would be BPM in years 2019 and onwards. Because AHRI did not
explicitly describe how hypothetical refrigerant regulations would
translate into accelerated uptake in furnace fans having BPM motors,
DOE did not account for an increased rate of ``whole-system'' CAC
replacements (and therefore furnace fan replacements) when evaluating
furnace fan BPM penetration forecasts. Using these assumptions, DOE
estimates that the percentage of installed BPM furnace fan motors in
2021 to be 29 percent (as compared to 24 percent \18\ estimated in the
December 2016 CAC ECS TSD). Further, DOE's estimates support AHRI's
claim that the installed base of BPM furnace fans is likely to grow to
40 percent by 2023 and 50 percent by the year 2025. Therefore, DOE has
used these values of BPM market penetration to re-evaluate the NOPR
analysis to calculate default low-stage fan power coefficients and fan
heat coefficients in the next section.
---------------------------------------------------------------------------
\18\ BPM estimate from 2016 CAC ECS TSD reflects the sum of CT-
BPM (9%) and CA-BPM (15%).
---------------------------------------------------------------------------
c. Determining Low-Stage Coefficients
In consideration of DOE's proposals regarding default fan power
coefficients, AHRI also asserted that DOE's analysis included incorrect
assumptions about the relationship between electrical power consumption
and delivered airflow, which they claimed should be a cubic
relationship based on fan affinity laws. AHRI provided aggregated data
from a selection of 78 furnace fans to support their assertions. Id. at
pp.3-4. Lennox and Rheem reiterated AHRI's comment, stating that the
application of the same default coefficient at part-load airflows is
not representative of the performance of the two-stage equipment
operation, as the fan efficiency improves as airflow is reduced thus
increasing overall system efficiency. (Lennox, No.19 at p.2, Rheem,
No.21 at pp.1-2) Lennox and Rheem also elaborated that fan affinity
laws show that fan speed and power have a cubic relationship, not the
constant relationship \19\ currently used in the test procedure. Id.
AHRI further claimed that of the 78 collected furnace fans in their
data set, there was not a statistically significant difference in full-
load performance (measured in Watts per cfm) between models having
furnace fans with PSC motors and models having furnace fans with PBM
motors. As a result, AHRI did not argue that the full-load default fan
power and heat coefficients should be changed but did suggest lower
default fan power and fan heat coefficients low-stage operation. AHRI
proposed default low-stage fan power coefficients of 322 W/1000 scfm
for conventional systems and 296 W/1000 scfm for mobile-home/space-
constrained systems.\20\ (AHRI, No.25 at pp.3-4) As indicated, Carrier,
Daikin, Emerson, Lennox, Nortek, and Rheem all referenced the AHRI
analysis in their comments and supported the alternate default fan
power coefficients proposed by AHRI. (Carrier, No.15 at p.2; Daikin,
No.24 at p.1; Emerson, No.14 at p.1; Lennox, No.19 at p.2; Nortek,
No.13 at pp.1-2; Rheem, No.21 at pp.1-2)
---------------------------------------------------------------------------
\19\ The DOE test procedure does not prescribe a constant
default fan power, but rather a constant default fan power
coefficient, so that the calculated fan power varies linearly with
air volume rate. See appendix M1, sections 3.3, 3.5.1, 3.7, and
3.9.1.
\20\ AHRI also provided corresponding default fan heat
coefficients of 1099 Btu/h/1000scfm and 1010 Btu/h/1000scfm for
conventional and mobile-home/space-constrained coil-only CACs,
respectively.
---------------------------------------------------------------------------
DOE understands the theoretical basis of fan laws which describe a
cubic relationship between fan shaft power and delivered air volume
rate for an idealized fan. However, real fan shaft power does not
always consistently follow the fan laws \21\ and motor efficiency
generally decreases as shaft power decreases from rated load,\22\ which
would cause motor input power to deviate from the cubic relationship
even if the shaft power followed it. The AHRI comment does not provide
a more
[[Page 64558]]
detailed breakdown of analytical results allowing confirmation of
general consistency of the two analytical approaches. As noted, DOE has
re-evaluated the NOPR analysis to calculate default low-stage fan power
coefficients and fan heat coefficients, using the assumption that BPM
furnace fan penetration is 40 percent in the year 2023 (the compliance
date of CAC energy conservation standards in terms of appendix M1
metrics). 10 CFR 430.32(c)(5). DOE re-analyzed the same dataset used in
the furnace fans rulemaking and applied a proportion of 40 percent BPM
and 60 percent PSC motors, while keeping all other elements of the
analysis unchanged (see 79 FR 506, Jan. 3, 2014). For the reasons
described in section III.C.1.e of this document, DOE did not consider
separate default fan power coefficients for space-constrained coil-only
CACs and is instead continuing to treat mobile-home and space-
constrained systems jointly. This evaluation results in default low-
stage fan power and heat coefficients that are lower than the values
proposed in the March 2022 CAC TP NOPR, and DOE is adopting these lower
values in this final rule. The fan motor re-weighting had negligible
impact on the full-load airflow values for default fan power and
default fan heat coefficients, therefore, DOE is not amending the full-
load values in this final rule, consistent with comments received from
AHRI. (AHRI, No.25 at p.3) The results of DOE's analysis are summarized
in Table III-1.
---------------------------------------------------------------------------
\21\ This catalog of several indoor air handling units
demonstrates on the 6th page examples of fan performance curves,
where the fan efficiency does not always follow a simple quadratic
curve: https://content.greenheck.com/public/DAMProd/Original/10002/IAH_catalog.pdf.
\22\ As per ANSI/AMCA Standard 241-21 (Test Procedure for
Calculating Fan Energy Index (FEI) for Commercial and Industrial
Fans and Blowers), the motor efficiency for variable-speed motors is
not always directly proportional to the load, as demonstrated in
Figure F.3. Source: https://www.amca.org/assets/resources/public/pdf/Publications/AMCA-214-21.pdf.
Table III-1--Default Fan Power and Fan Heat Coefficients for Coil-Only CACs and HPs
----------------------------------------------------------------------------------------------------------------
Default fan
Air volume power Default fan heat
System type rate (%) coefficient (W/ coefficient (Btu/h/
1000scfm) 1000scfm)
----------------------------------------------------------------------------------------------------------------
Conventional Coil-Only...................................... 100 441 1505
75 335 1143
Mobile-Home and Space-Constrained Coil-Only................. 100 406 1385
75 308 1051
----------------------------------------------------------------------------------------------------------------
d. Interpolated Coefficients Between 75 and 100 Percent Air Volume Rate
In the March 2022 CAC TP NOPR, DOE also stated that the reduced air
volume rate used for low-stage operation of two-stage coil-only systems
may be higher than 75 percent of the full-load air volume rate, if the
manufacturer's instructions specify a higher part-load air volume rate.
DOE proposed that in such cases, (i.e., in any case where the reduced
air volume rate is greater than 75 percent of the full-load air volume
rate) the default fan power values associated with full-load air volume
rate be used. However, DOE hypothesized that in these scenarios, the
appropriate default fan power coefficient and default fan heat
coefficient may be values between the reduced values discussed above
and the values used for full-load air volume rate. DOE set out two
alternative options to its proposed approach: (1) allowing the reduced
value up to a threshold value, e.g., 80 percent of full-load air volume
rate, above which the full-load value would be required, and (2)
requiring a linear interpolation of the default fan power coefficient
between the reduced value at 75 percent of full-load air volume rate to
the full-load value at 100 percent.\23\ 78 FR 16830, 16835.
---------------------------------------------------------------------------
\23\ For example, for non-mobile-home and non-space-constrained
systems, if a linear interpolation of the default fan power
coefficient is required, it would be equal to 360 + (441-
360)*(%FLAVR-75%)/(100%-75%), where %FLAVR is the reduced air volume
rate used for the test expressed as a percentage of the full load
air volume rate.
---------------------------------------------------------------------------
AHRI, Carrier, Daikin, Emerson, Lennox, and Nortek all supported
the second alternative option set forth by DOE, i.e., requiring a
linear interpolation of the default fan power coefficient based on
percentage full-load air volume rate. (AHRI, No.25 at p.6; Carrier,
No.15 at p.2; Daikin, No.24 at p.1; Emerson, No.14 at pp.1-2; Lennox,
No.19 at p.2; Nortek, No.13 at p.1) AHRI provided a table of power
consumption rate as a function of airflow percentage and stated that a
third-order equation would be most accurate, however intermediate
values for default fan power coefficient would be most easily
calculated using linear interpolation. (AHRI, No.25 at pp.4-6)
Based on the comments, DOE is finalizing the approach of requiring
linear interpolation of default fan power and default fan heat
coefficients for all tests where the specified airflow is between 75
percent and 100 percent of the full load air volume rate.
e. Considerations for Space-Constrained Systems
As previously mentioned in section III.C.1.b, NCP supported AHRI's
claims that due to the FER furnace fan standards coming into effect in
2019, and due to anticipated refrigerant regulations, the relative
penetration rate of furnace fans with BPM motors is higher than the
proportion estimated by DOE in the January 2017 CAC TP Final Rule.
(NCP, No.16 at pp.8-9) NCP also remarked that DOE's proposal for
default fan power coefficients implies that space-constrained coil-only
units are similar to those of mobile homes, and implies that both
should use a default fan power and capacity adjustment that is
representative of operation at a minimum external static pressure (ESP)
of 0.30 inches w.c.\24\ NCP asserted that data based on mobile homes is
not an appropriate basis for space-constrained condensing units used in
multi-family housing applications. NCP claimed that although the size
of the indoor units is similarly restricted in mobile-home and space-
constrained applications, mobile-home applications do not limit the
size of the outdoor unit in the same way as space-constrained
installations, which require a smaller footprint for the condensing
unit. NCP elaborated that this discrepancy allows for mobile-home
systems to have a relatively larger condenser coil surface area
(providing improved performance) and that their models of space-
constrained outdoor units do not have sufficient space to increase the
condenser coil size. NCP thus asserted that the default fan power
coefficients proposed by DOE in the March 2022 CAC TP NOPR remains
unrealistic for NCP's space-constrained CAC systems and would prohibit
NCP from meeting the minimum energy efficiency standard. NCP requested
that if the Department does not continue to waive requirements for
coil-only testing of space-constrained condensing units, DOE should
amend the default fan
[[Page 64559]]
power and fan heat coefficients to reflect real world conditions. (NCP,
No.16 at pp. 7-8) NCP provided confidential information regarding the
performance of their ``Through-the-Wall'' (TTW) space-constrained
condensing units when paired with various indoor unit air handlers,
including different NCP-branded air handlers and with other brands of
furnaces (indicative of a coil-only installation). NCP then
incorporated its findings along with the data provided by AHRI and
proposed a default fan power coefficient of 321 Watts per 1000 scfm for
space-constrained coil-only CAC systems operating at low-stage airflow.
Id. at p.9.
---------------------------------------------------------------------------
\24\ Appendix M1 requires that both ducted space-constrained and
ducted mobile-home CACs be tested at a minimum ESP of 0.30 inches
w.c. 87 FR 16834 (Mar. 24, 2022) (citing 82 FR 1426, 1453 (Jan. 5,
2017)).
---------------------------------------------------------------------------
In response to NCP's assertion that separate test procedure
considerations should be given for default fan power coefficients for
space-constrained CAC systems vs those for mobile-home CAC systems, DOE
notes that this topic was previously discussed in the January 2017 CAC
TP Final Rule. In that rule DOE determined, with stakeholder support,
appropriate default fan power and default fan heat coefficients for
mobile home coil-only systems required to be tested at a minimum
external static pressure of 0.30 in. w.c. 82 FR 1426, 1451-1452. DOE
also noted in that final rule that recommendation #2 of the January
2016 Appliance Standards and Rulemaking Federal Advisory Committee
(ASRAC) CAC/HP Working Group Term Sheet (2016 CAC Term Sheet)
recommended 0.30 inches w.c. as the minimum external static pressure
requirement for testing space-constrained CACs Id. DOE is maintaining
the determination from the January 2017 CAC TP Final Rule and the
current test procedure approach, which uses the same default fan power
coefficient and default fan heat coefficient for space-constrained and
mobile home CAC.
2. Variable-Speed Coil-Only Test Procedure
a. Background
As discussed, appendices M and M1 contain provisions for testing
split-system CAC/HPs equipped with ``coil only'' indoor units that, in
a field installation, are paired with an existing furnace or other air
handler that includes the fan required to circulate conditioned air
through ductwork. These provisions apply to single-stage and two-stage
systems and address only two levels of air volume rate, for full-load
and minimum operation.\25\ Appendices M and M1 do not include
provisions for testing variable-speed systems equipped with coil-only
indoor units (``VSCO'' CACs). In the March 2022 CAC TP NOPR, DOE
discussed waiver requests that it had received from multiple
manufacturers regarding the test provisions for VSCO CACs. 82 FR 16830,
16836-16837. The various waiver requests are summarized in this final
rule in Table III-2.
---------------------------------------------------------------------------
\25\ Section 3.1.4.1.1.c (cooling full-load air volume rate),
section 3.1.4.2.c (cooling minimum air volume rate), section
3.1.4.4.2.c (heating full-load air volume rate), and section
3.1.4.5.2.d (heating minimum air volume rate) of appendix M1.
---------------------------------------------------------------------------
With the exception of the Goodman Manufacturing Company, L.P.
(``Goodman'') petition for waiver (86 FR 40534 (July 28, 2021)), all
petitioners submitted petitions for waiver for products that use ``non-
communicative'' conventional controls, i.e., controls that use low-
voltage on-off signals from the thermostat to indicate the need for
conditioning in the conditioned space. As required under the specified
alternate test procedures for these ``non-communicative variable-speed
coil-only systems,'' they must be tested according to the appendix M
provisions applicable to variable-speed systems (e.g., three different
compressor speeds in the cooling mode), except that the subject systems
must be tested using the full-load cooling air volume rate at all test
conditions. (GD Midea, EERE-2017-BT-WAV-0060, No. 1, pp. 1-3; TCL,
EERE-2018-BT-WAV-0013, No. 1, pp. 2-4; LG, EERE-2019-BT-WAV-0023, No.
1, pp 3-4) DOE noted that the waivers for non-communicative systems
indicated only that ``compressor speed varies based only on controls
located on the outdoor unit.'' (GD Midea, EERE-2017-BT-WAV-0060, No. 1,
p. 6; TCL, EERE-2018-BT-WAV-0013, No. 1, p. 4; LG, EERE-2019-BT-WAV-
0023, No. 1, pp 2) An interim test procedure waiver was also granted to
Goodman for their ``communicative'' variable-speed, coil-only CAC/HPs.
Goodman's petition claimed that for their systems, both the outdoor
unit and indoor coil communicate with each other to control the
variable-speed compressor, along with the multi-speed indoor fan. 86 FR
40534, 40539. The Goodman interim waiver test procedure specifies use
of the cooling full-load air volume rate for the full-load cooling and
full-load heating tests; and the cooling minimum air volume rate for
the cooling minimum, heating minimum, cooling intermediate, and heating
intermediate tests. Id.
Table III-2--Status and Details of Variable-Speed, Coil Only (VSCO) Waiver Requests
----------------------------------------------------------------------------------------------------------------
Manufacturer Petition description Docket Status
----------------------------------------------------------------------------------------------------------------
GD Midea Heating & Ventilating Non-communicating VSCO. EERE-2017-BT-WAV-0060.............. Interim and
Equipment Co., Ltd. (GD Midea). Full load air volume Waiver Granted.
rate used for
intermediate and
minimum.
TCL air conditioner (zhongshan) Non-communicating VSCO. EERE-2018-BT-WAV-0013.............. Interim and
Co. Ltd. (``TCL AC''). Full load air volume Waiver Granted.
rate used for
intermediate and
minimum.
LG Electronics U.S.A., Inc. Non-communicating VSCO. EERE-2019-BT-WAV-0023.............. Interim Granted.
(LGE). Full load air volume
rate used for
intermediate and
minimum.
Goodman........................ Communicating VSCO. EERE-2021-BT-WAV-0001.............. Interim Granted.
Minimum air volume
rate used for
intermediate and
minimum.
----------------------------------------------------------------------------------------------------------------
In the March 2022 CAC TP NOPR, DOE explained that it was
reconsidering its approach to the waivers for the non-communicative
VSCO systems. First, DOE explained that the waiver petitions had not
provided information regarding, nor had DOE evaluated, the compressor
speed selections used for different test conditions specified in
appendix M or M1. 87 FR 16830, 16836. DOE elaborated that it had also
not compared these speed selections with those used by blower-coil
variable speed systems for the same test conditions. Id. DOE determined
that based on the
[[Page 64560]]
information received and evaluated, it could not conclude that the
alternate test procedures specified in the waivers are representative
of average use cycles of CAC/HPs. Id. DOE proposed provisions as
generally prescribed in the relevant waivers, except that, for all
variable-speed coil-only systems, regardless of communicative
capability, use of a reduced-air volume rate would be allowed for part-
load operation, i.e., using the cooling minimum air volume rate for the
cooling minimum, heating minimum, cooling intermediate, and heating
intermediate tests. 87 FR 16830, 16837-16838. The proposed test
procedure also incorporated the reduced default fan power and default
fan heat coefficients at reduced air volume rates discussed in section
III.C.1 of this document.
Regarding indoor airflow rate for VSCO systems, DOE pointed out
that the test procedure for two-stage coil-only systems is premised on
the system using a two-stage thermostat and associated wiring that
responds to indoor temperature measurements and sends voltage signals
that enable two-stage control of both the compressor speed and the
indoor fan speed. 87 FR 16830, 16836-16837. DOE similarly assumed the
presence of necessary wiring for the installation of variable-speed
systems. Id. DOE elaborated that if the system does not include the
capability to control an existing furnace fan at two air volume rates,
the manufacturer would have the option of specifying minimum/
intermediate air volume rates equal to the full-load air volume rate.
Id.
Regarding compressor speed control for VSCO systems, DOE proposed
to define ``communicating control'' in the context of variable-speed,
coil-only CAC/HPs in order to differentiate between the test procedure
provisions that would be applicable to communicating systems from those
applicable to non-communicating systems. 87 FR 16830, 16837-16838. See
section III.C.2.b. DOE further proposed provisions for setting
compressor speed reflecting the attributes of the controls.
Specifically, DOE proposed to require that non-communicative variable-
speed coil-only systems be tested using an on-off control signal
consistent with the control characteristics and also eliminating the
EV test for cooling and H2V for heating as well
as including H22, H21, and H31 for
heating. In contrast, DOE proposed that systems that meet the newly
proposed criteria for ``communicating'' control would use compressor
speeds and tests consistent with the existing variable-speed test
procedure for blower-coil systems. Id.
With respect to DOE's proposal to add testing provisions for VSCO
CACs in appendix M1, Carrier, Joint Advocates, Lennox, Nortek, and
Rheem commented that they supported DOE's proposals to add testing
provisions for variable-speed coil-only CAC/HPs. (Carrier, No.15 at
p.1, Joint Advocates, No.18 at p.2, Lennox, No.19 at p.3, Nortek, No.13
at p.2, Rheem, No.21 at p.2) Carrier stated that they agreed that a
communicating and non-communicating procedure should be created, and
supported DOE's proposed test procedure for each type of system.
(Carrier, No.15 at p.1) The Joint advocates added that they supported
incorporating provisions for testing variable-speed coil-only units to
ensure that the test procedure reflects differences in system controls
architecture between communicating and non-communicating systems.
(Joint Advocates, No.18 at p.2) They further commented that DOE's
hybrid approach for aligning minimum air volume requirements between
two-capacity and variable-speed coil-only units (for both communicating
and non-communicating systems) was logical, as non-communicating
systems have characteristics of both variable-speed and two-stage
systems due to limitations of the less sophisticated control systems.
Id. Lennox stated that DOE's proposal provides a consistent test method
according to defined system capabilities while allowing for expanded
opportunity for variable speed equipment to be installed in replacement
applications with existing furnace or modular blowers. (Lennox, No.19
at p.3) Nortek explicitly stated that they were in favor of adopting
the test procedures that were contained in the waivers, giving the
Goodman waiver (86 FR 40534 (July 28, 2021)), as an example. AHRI
commented that they agreed that systems meeting the criteria for
variable-speed communicating coil-only CAC or HP definition should
follow the existing variable-speed test procedure, although AHRI
proposed an alternate definition for communicating control as described
in section III.C.2.b of this document. (AHRI, No.25 at p.6)
b. Test Differences Based on Communicating Capability
As previously stated, the test procedure for two-stage coil-only
systems is premised on the system using a two-stage thermostat and
associated wiring that responds to indoor temperature measurements and
sends voltage signals that enable two-stage control of both the
compressor speed and the indoor fan speed. A more sophisticated control
approach is required to enable a variable speed system to modulate
compressor speed control (e.g., proprietary thermostat, serial
communication wiring, and/or electronic sensors at the indoor coil). In
the March 2022 CAC TP NOPR, DOE proposed to define ``variable-speed
communicating oil-only central air conditioner or heat pump'' in
section 1.2 of appendix M1, to distinguish variable-speed coil-only
systems with such controls, as a variable-speed compressor system
having a coil-only indoor unit that is installed with a control system
that (1) communicates the difference in space temperature and space
setpoint temperature (not a setpoint value inferred from on/off
thermostat signals) to the control that sets compressor speed; (2)
provides a signal to the indoor fan to set fan speed appropriate for
compressor staging and air volume rate; and (3) has installation
instructions indicating that the required control system meeting both
(1) and (2) must be installed. 87 FR 16830, 16837.
DOE also proposed to define variable-speed systems that do not have
this communicating feature as a variable-speed compressor system having
a coil-only indoor unit that does not meet the definition of variable-
speed communicating coil-only central air conditioner or heat pump. Id.
DOE elaborated that variable-speed coil-only systems that meet the
``communicating'' definition would be tested like any other variable-
speed system, except that the heating full-load air volume rate would
be equal to the cooling full-load air volume rate, and the intermediate
and minimum cooling and heating air volume rates would all be the
higher of (1) the rate specified by the installation instructions
included with the unit by the manufacturer and (2) 75 percent of the
full-load cooling air volume rate. Id.
DOE further proposed that those variable-speed coil-only systems
that are not ``communicating'' as defined above would be tested with
additional limitations as if they have some variable-speed system
characteristics and some two-stage coil-only system characteristics.
Specifically, (a) the outdoor unit and/or the indoor unit would be
provided with a control signal indicating operation at high or low
stage, rather than testing with compressor speed fixed at specified
speeds, and (b) air volume rates would be determined consistent with
the requirement for two-stage coil-only systems. Id. A key implication
of (a) is that there would be no intermediate compressor speed
operation. Under DOE's proposed test procedure, many of
[[Page 64561]]
the requirements associated with variable-speed operation would,
however, be retained. For example, such systems would be allowed to
have ``minimum speed-limiting'' control for heat pump mode (see the
alternative calculations representing minimum-speed operation in
appendix M1, section 4.2.4.b). The test method for non-communicating
variable-speed coil-only systems would include requiring tests for
minimum-speed operation for both the 35 [deg]F and 17 [deg]F heating
test conditions so that the HSPF2 calculations utilize test results for
appropriate compressor speeds. Also, the full compressor speed during
heating mode operation would be allowed to vary with outdoor
temperature, there would be an H1N test to represent the
nominal capacity, and the same provisions for calculation of full-speed
capacity and power applied to conventional variable-speed systems would
be used (see, e.g., the calculations in appendix M1, sections 3.6.4,
4.2.4.c and 4.2.4.d). If a manufacturer chooses to run the optional
H12 test (i.e., if compressor speed for the H1N
test is different than compressor speed for the H32 test,
and the manufacturer chooses to run the H12 test rather than
use the standardized slope factors described in appendix M1, section
3.6.4.b), then the test would be run with over-ride of compressor speed
using the same speed as used for the H32 test. This is the
only test for which such over-ride would be allowed.
To ensure consistency of testing, it may be necessary for
manufacturers to certify whether a variable-speed coil-only rating is
based on non-communicating or communicating control. However, this
change was not proposed in the March 2022 CAC TP NOPR and may be
considered in a separate rulemaking.
In the March 2022 CAC TP NOPR, DOE acknowledged that there may be
variable-speed control technology that cannot be tested according to
the proposed test approach described previously for non-communicating
variable-speed coil-only systems. 87 FR 16830, 16838. Specifically, the
test approach may not result in tests that meet the stability
requirements for testing (i.e., the measurements might not meet the
tolerance requirements in Table 2 of ANSI/ASHRAE 37-2009, ``Methods of
Testing for Rating Electrically Driven Unitary Air-Conditioning and
Heat Pump Equipment'' (``ASHRAE 37-2009''), which is incorporated by
reference by the DOE test procedure). Or the proposed test procedure
might evaluate such a basic model in a manner so unrepresentative of
its true energy consumption characteristics as to provide materially
inaccurate comparative data. Id. DOE stated that in this case, the
manufacturer would be able to petition DOE for a waiver and include a
suggested alternate test procedure as provided in 10 CFR 430.27. DOE
elaborated that as part of its review of such a waiver and alternate
test procedure, DOE would consider the correlation between results of a
suggested alternate test procedure and results of testing when using
the two-stage two-wire controls expected to be available in a general
coil-only system installation, recognizing that the latter testing may
involve dynamics that exceed the measurement tolerances discussed
above. DOE would also consider the control hardware involved in
achieving appropriate control for indoor and outdoor conditions and
some understanding of how the control works. Id.
With respect to DOE's proposal to define variable speed
communicating coil-only CACs and HPs, Emerson supported the
differentiation of communicating and non-communicating variable speed
CACs that maintains the ability to set compressor speed and optimize
airflow relative to the compressor speed. (Emerson, No.14 at p.3) The
Joint Advocates supported DOE's proposed definition but encouraged DOE
to revise the definition to clarify that the installation instructions
refer to those of the indoor unit (not of the control system). (Joint
Advocates, No.18 at pp.2-3) AHRI commented that they supported the
concept of the definition but recommended modifications to be more
inclusive of other approaches. AHRI proposed an alternate definition as
follows:
Variable-Speed Communicating Coil-Only Central Air Conditioner or
Heat Pump means a variable-speed compressor system having a coil-only
indoor unit that is installed with communicative controls to change the
compressor speed by 3 or more speeds and indoor air flow by 2 or more
speeds and controls the system by monitoring the change in system
control parameter/s and automatically sets the compressor speed, indoor
air flow and other system components as required to maintain the indoor
room temperature. (AHRI, No.25 at p.6)
Carrier, Daikin, Nortek, and Samsung incorporated AHRI's proposed
definition in their comments. (Carrier, No.25 at pp.2-3; Daikin, No.24
at p.2; Nortek, No.13 at p.2; Samsung, No.22 at p.2) AHRI, Carrier,
Daikin, Nortek, and Samsung all agreed that DOE's proposed definition
is too restrictive and should be modified to allow for potential
alternate control strategies that could be used to properly control
compressor speed and coordinate with indoor fan speed. Id. AHRI,
Daikin, and Samsung stated that communication of set point and indoor
temperature is not the only parameter that can be used to set fan and
compressor speeds, suggesting that it is not necessary to achieve
proper compressor control, and provided hypothetical examples of other
control parameters that could be used to set compressor speeds, such as
outside air conditions, indoor humidity levels, or refrigerant
pressures and temperatures. (AHRI, No. 25 at p.6; Daikin, No.24 at p.2;
Samsung, No.22 at pp.1-2) Daikin elaborated that the DOE definition
should be modified to allow for technology advancements in control
technology and recommended a definition similar to the definition for
``demand defrost control systems'', which requires that the control
scheme ``monitor one or more parameters that always vary.'' (Daikin,
No.24 at p.2) Samsung elaborated that DOE's proposal would require a
communicating thermostat, which they claimed to be unnecessary for
achieving appropriate compressor and fan control and stated would add
unnecessary cost to the consumer. (Samsung, No.22 at pp.1-2)
While DOE acknowledges that there may be other control approaches
to set compressor speed other than approaches that communicate the
difference in space temperature and space setpoint temperature, DOE
notes that minimizing this difference between a controlled parameter
and its setpoint is the key function of the control system, and use of
this parameter to set conditioning system operation is a fundamental
feature of most modern control systems. In its proposal, DOE
distinguished between communicating and non-communicating based on
whether the system includes this fundamental aspect of control systems.
DOE premised its proposals on the understanding that non-communicating
systems would likely encounter greater issues regarding the
representativeness of field-versus-tested performance, as compared to
communicating systems.
As mentioned, DOE acknowledges that other control approaches may
provide control represented adequately by the fixed-speed testing that
is currently prescribed in its test procedures for CAC/HP system but
given the fundamental difference in the control approach, i.e., not
using information about the space temperature deviation from setpoint,
DOE does not believe there has been sufficient
[[Page 64562]]
information provided confirming this adequacy. As DOE considers more
comprehensive test procedure changes in a future rulemaking, it will
further evaluate this issue and is open to revising the definition
accordingly. Also, the proposed definition does not restrict other
control parameters in addition to the space temperature offset from
setpoint being used by the control system to set system operation.
Hence, DOE is adopting the definition for communicating and non-
communicating variable-speed coil-only system as proposed.
As previously introduced, DOE also considered that it may be
necessary for manufacturers to certify whether a variable speed coil-
only rating is based on non-communicating or communicating control but
did not propose any certification requirements in the March 2022 CAC TP
NOPR and instead stated that these changes may be considered in a
separate rulemaking. 87 FR 16830, 16838.
In response, the Joint Advocates supported the concept that DOE
require certification of VSCO units as communicating or non-
communicating and encouraged DOE to finalize all pertinent
certification provisions as soon as possible. (Joint Advocates, No. 18
at p. 2) As indicated, DOE may consider certification requirements in a
separate rulemaking.
c. Applicability to Variable Speed Blower Coil Systems
In the March 2022 CAC TP NOPR, DOE further discussed that
installations using non-communicating controls may not be limited only
to variable-speed coil-only systems but could also occur with variable-
speed blower-coil systems. 87 FR 16830, 16838. DOE noted that the
proposed test procedure distinguishes between the testing approach used
for coil-only configurations and the testing approach used for blower-
coil configurations. Id. DOE argued that as coil-only installations are
much more likely than blower-coil installations to involve use of both
the existing furnace fan and existing controls, the non-communicating
test procedure should be reflective of coil-only installations because
they are more representative than blower coil installations. Id.
With respect to the applicability of the proposed VSCO testing
provisions to variable speed blower-coil CACs and HPs, Emerson
commented that the ability to set compressor speed and optimize airflow
rate relative to compressor speed may be even more important in blower-
coil systems than in coil-only systems and requested that DOE address
this point. (Emerson, No. 14 at p. 3) Trane similarly asserted that it
is important that DOE addresses non-communicating, blower-coil variable
speed systems in addition to the proposed provisions for coil-only
systems. (Trane, No. 10 at p. 2) Trane stated that such blower-coil
systems have the same issue of misrepresenting the applied performance
(i.e., the performance measured in a field installation) by allowing
them to use the communicating, variable speed procedures. Id. Trane
elaborated that the wiring and control of such systems is obvious from
the installation instructions, and they operate in a similar fashion to
the furnace-coil (i.e., coil-only) combinations with one or two-stage
fan operation. Id. Trane provided an example \26\ of such a product
where a variable-speed CAC outdoor unit is certified with an indoor
blower-coil unit only capable of one stage of airflow operation, and
the connections are non-communicating 24V signals between equipment and
thermostat. Id.
---------------------------------------------------------------------------
\26\ Trane provided an example of a Bosch system with AHRI
reference number 206395973 and provided a link to the installation
instructions: https://www.bosch-thermotechnology.us/us/media/country_pool/documents/bosch_ids_bva15_iom_10.2020.pdf.
---------------------------------------------------------------------------
DOE acknowledges the concerns expressed by Trane and Emerson that
questions remain regarding use of non-communicating controls for
blower-coil systems and whether the compressor and/or fan speeds used
for testing such systems are representative of field operation.
However, DOE initiated this rulemaking to address a focused group of
known issues, including those that have been raised through the test
procedure waiver process. As noted in the March 2022 CAC TP NOPR, DOE
limited its proposals addressing potential concerns about variable-
speed systems to coil-only systems and may more comprehensively address
these issues for all variable-speed systems in a future rulemaking that
will satisfy the 7-year lookback requirements (see 42 U.S.C.
6293(b)(1)(A)). 87 FR 16830, 16838.
d. Represented Values and Testing Requirements
Coil-only testing approaches for variable-speed systems address the
installation of variable-speed technology in which the newly installed
system uses existing components, for example an existing furnace fan.
For single-capacity and two-capacity split-system air-conditioners,
certification requirements anticipate this likely installation scenario
by requiring that such models include performance representations with
a coil-only combination representative of the least-efficient
combination in which the outdoor unit is sold (see 10 CFR
429.16(a)(1)). For variable speed split-system air conditioners,
represented values are required for every individual combination
distributed in commerce, including all coil-only and blower-coil
combinations (see 10 CFR 429.16(a)(1)). However, there is no
requirement that each model of outdoor unit include at least one
representation based on the least-efficient coil-only combination
distributed in commerce. In the March 2022 CAC TP NOPR, DOE considered
whether such a requirement may be appropriate for variable-speed
systems. 87 FR 16830, 16838-16839.
Through a review of product datasheets and installation
instructions, DOE found that there is a wide range of instruction
regarding whether variable-speed CAC systems must be paired with
specific models of indoor units and/or air movers (e.g., furnaces) in
order to achieve the represented performance. Id. DOE identified that
some literature is very clear that achieving the rated performance for
a given outdoor unit is contingent on installation with specific
components (e.g., communicating controls and indoor fans capable of
variable-speed operation), while other literature does not mention the
need for such components. Id. DOE identified that this latter group is
not limited to brands that have been granted test procedure waivers or
interim waivers for testing variable-speed coil-only systems,
indicating that the issue is more broadly applicable to variable-speed
CAC installations and it is possible that variable-speed systems are
being installed in coil-only applications for which representations of
performance are not representative of actual performance (because the
represented values are based on blower-coil pairing while the
installation scenario is coil-only). Id. However, because less than 5
percent of variable speed system installations are coil-only \27\ and
the number of certified combinations of VSCO systems is a small
percentage \28\ of overall variable
[[Page 64563]]
speed system certifications, DOE concluded that VSCO installations are
not likely representative of variable speed system operation as a
whole. Id.
---------------------------------------------------------------------------
\27\ Based on information DOE has from the previous energy
conservation standards rulemaking pertaining to central air
conditioners and heat pumps. See 82 FR 1786.
\28\ For example, there are roughly 27,000 combinations listed
in the AHRI Database for which a non-zero intermediate indoor air
volume rate is listed, indicating that the combination is a
variable-speed model. DOE reviewed the current certifications in the
certification compliance management system and found that there are
approximately 400 variable-speed coil-only combinations,
representing roughly 1.5 percent of the total variable speed
combinations certified to the Department.
---------------------------------------------------------------------------
In the March 2022 CAC TP NOPR, in order to improve
representativeness of the representations of VSCO installations DOE
proposed tested-combination requirements pertaining to variable speed
systems, summarized here in Table III-3. 87 FR 16830, 16839.
Table III-3--Proposed Tested Combination Requirements for Variable Speed
Split-System CACs
------------------------------------------------------------------------
Required tested
Scenario combination
------------------------------------------------------------------------
Outdoor unit is distributed in commerce with any Variable Speed Non-
non-communicating coil-only combination(s). Communicating Coil-
Only.
Outdoor unit is distributed in commerce with any Variable Speed
communicating coil-only combination(s), but no Communicating Coil-
non-communicating coil-only combination. Only.
Outdoor unit is only distributed in commerce Variable Speed Blower-
with blower-coil combinations. Coil.
------------------------------------------------------------------------
In the March 2022 CAC TP NOPR, DOE noted that the variable-speed
coil-only waiver petitions addressed both air-conditioners and heat
pumps. 87 FR 16380, 16389. Thus, DOE considered whether the coil-only
tested combination requirement should apply to variable speed heat
pumps and/or to single-stage and/or two-stage heat pumps. Id. DOE noted
that coil-only heat pumps allow the heating system to provide heat
either using the furnace or the heat pump. Id. There has been greater
interest in such systems in recent years, since they provide heating
with a furnace in extreme cold conditions for which a heat pump may
have limited capacity and/or reduced efficiency.\29\ DOE proposed to
require coil-only tested combinations for variable-speed heat pumps,
but not for single- and two-stage heat pumps, because DOE expects that
the representativeness of blower-coil tests would deviate more from
coil-only tests for variable-speed systems, due to the use of a
variable-speed indoor fan and use of an intermediate air volume rate
used for intermediate-speed testing for variable-speed systems. Id. DOE
argued that the test procedures for single-stage and two-stage heat
pumps are more restrictive with regard to allowed air volume rates and
thus performance differences between blower-coil and coil-only
operation would be less. Id.
---------------------------------------------------------------------------
\29\ https://www.trane.com/residential/en/resources/glossary/dual-fuel-heat-pump/ (last accessed 2/4/2022).
---------------------------------------------------------------------------
Regarding variable-speed coil-only systems using indoor units
manufactured by independent coil manufacturers (``ICMs''), in the March
2022 CAC TP NOPR, DOE noted that the regulations require certification
of the performance of every individual combination distributed in
commerce, including both blower-coil and coil-only (see 10 CFR
429.16(a)(1)). Id. However, a tested combination for an ICM indoor unit
must include the least-efficient outdoor unit with which the indoor
unit is distributed in commerce (see 10 CFR 429.6(b)(2)(i)). Id. DOE
stated in the NOPR that it does not believe any changes are needed with
respect to ICM certifications as the current regulations already
encompass representing all combinations distributed in commerce,
including noncommunicating and communicating variable-speed coil only
systems. Id. Further, DOE noted that the least-efficient outdoor unit
with which the indoor unit is distributed in commerce is not likely to
be a variable-speed system, and thus the question of communicating or
non-communicating coil-only status does not apply. Id.
DOE received comments from multiple stakeholders regarding its
proposals for represented values and testing requirements for VSCO CACs
and HPs.
Lennox agreed with DOE's proposal not to require that all variable-
speed CACs and HPs have a coil-only representation, as is required for
single- and two-stage split air-conditioning systems. (Lennox, No. 19
at p. 3)
Rheem disagreed with DOE's proposal to implement differing test
methods for communicating and non-communicating VSCO systems. (Rheem,
No. 21 at p. 2) Rheem elaborated that even though they support the DOE
proposal to expand the federal test procedure to account for coil-only
variable speed systems, the exclusive distinction between communicating
and non-communicating classifications for coil-only variable speed
systems creates additional complexity and has the potential to add more
test burden while reducing market flexibility. Id. Rheem stated that
ideally there would only be one test procedure for coil-only variable
speed systems, and preferably the one test would be the non-
communicating method, as this would likely represent the least
efficient system that may be installed the field. Id. Rheem recommended
that DOE reconsider the merits of implementing differing test methods
and suggested further study by DOE to quantify the difference in
efficiency representation between the test methods for communicating
versus non-communicating prior to incorporating this into the final
rule. Id.
DOE is working to better understand the differences in performance
between communicating and non-communicating systems but believes that
the fundamental differences in the control architecture of the two
approaches will lead to performance differences. For example, DOE
expects that non-communicating VSCO systems, when subjected to an
applied load, will likely demonstrate ``hunting'' for compressor speed,
fan speeds, and valve positions, which would reduce the measured
efficiency and potentially invalidate test results. For communicating
VSCO systems, however, DOE expects that these systems will be more
likely to include the requisite hardware and controls architecture to
accurately and repeatably set position of modulating components during
testing.
Trane commented that although DOE's recommendations for variable-
speed coil-only test procedures were a good start at addressing 24V
coil-only ratings with variable speed outdoor units, it needs to be
expanded. (Trane, No. 10 at pp. 1-2) Trane specified that in situations
where two-stage thermostats are paired with a two-stage airflow capable
furnace, the proposed procedure is a reasonable rating approach, but
that in the converse case with a single-stage thermostat or a single-
stage airflow furnace, the proposed procedure will inflate the unit
efficiency. Id. Trane recommended that two-different `coil-only
ratings' should be listed for such systems. Id. Trane elaborated that
an accessory note would indicate the applicable installation (1-stage
or 2-stage). Id. The rating
[[Page 64564]]
procedure for the 1-stage case would essentially follow the single
capacity system rating procedures, whereas the 2-stage case would
follow the procedure proposed by DOE in the March 2022 CAC TP NOPR. Id.
Trane also provided two connection diagrams \30\ as examples. Id. Both
diagrams showed connection with either a 1-stage thermostat and indoor
unit or a 2-stage thermostat and indoor unit. Id.
---------------------------------------------------------------------------
\30\ Trane provided examples of two Bosch systems with AHRI
reference numbers 206395973 and 206395967 and provided a link to the
installation instructions: https://www.bosch-thermotechnology.us/us/media/country_pool/documents/bosch_ids_bovb18_iom_10.2020.pdf.
---------------------------------------------------------------------------
DOE notes that representations of performance for both single-stage
and two-stage installations are not required for two-stage coil-only
systems. The two-stage coil only test provisions in the current DOE
test procedure are premised on the installation location having two-
stage thermostat wiring (Final Rule Technical Supporting Document,
EERE-2014-BT-STD-0048, No. 98, p. 8-25). DOE similarly assumes the
presence of the necessary wiring for the installation of variable-speed
coil-only systems in two-stage configuration.
Daikin commented that due to the nature of variable-speed CAC and
HP, having a coil-only representation requirement for ICMs may be
appropriate. (Daikin, No. 24 at p. 2) DOE notes that the current
requirements in 10 CFR 429.16 already require a representation for
every combination distributed in commerce, and hence any coil-only
product distributed in commerce by an ICM would already be required to
have a coil-only representation for variable-speed combinations with
which it is distributed in commerce. The further clarification of non-
communicating VSCO combinations in this rule extends that requirement
such that there must at least be a representation based on the non-
communicating VSCO test procedure if non-communicating combinations are
distributed in commerce.
Daikin and Rheem disagreed with the proposal to require the tested
combination to be coil-only for variable-speed systems that are
distributed in commerce in some cases with coil-only combinations.
(Daikin, No. 24 at p. 2; Rheem, No. 21 at p. 2) Daikin claimed that a
mandatory coil-only tested combination requirement for variable speed
systems would burden manufacturers of such systems with additional
testing requirements and would force lower represented values not
indicative of variable speed performance in typical installations.
(Daikin, No. 24 at p. 2) Daikin stated that manufacturers would still
test a blower-coil combination if the regulations require them to test
a coil-only combination, because of the vast majority of full-system
installations for VS systems. Id. Although Daikin did not explain why a
manufacturer couldn't test a coil-only combination and use an
alternative efficiency determination method (``AEDM'') to determine the
representative value for blower-coil systems with which the same
outdoor unit is paired, DOE acknowledges that the wider range of air
volume rates allowed with blower-coil testing as compared with coil-
only testing \31\ could make the use of testing (as opposed to an AEDM)
more important in determination of an accurate representation for
blower-coil systems than for coil-only systems. In addition, the
Emerson comments described in the following paragraph suggest that many
variable-speed outdoor models with blower-coil representations may be
distributed in commerce for a small percentage of installations in
coil-only combinations (see Emerson, No. 14 at p. 2). Although not
explicitly mentioned in comments addressing this topic, DOE realizes
that manufacturers may have already completed testing for many models
in advance of the January 1, 2023, date on which appendix M1 will be
required--requiring a coil-only representation at this late stage may
require additional testing. Thus, DOE is partially retracting the
proposed requirement for a coil-only tested combination for VS systems
distributed in commerce in coil-only combinations. Specifically, DOE is
maintaining this requirement only for non-communicating coil-only
combinations. As already discussed, the control approach for non-
communicating systems is fundamentally different than the control
approach for communicating systems. Hence, DOE is not convinced that a
test using the provisions for communicating VS systems (either blower-
coil or coil-only) would provide sufficient indication of non-
communicating performance to allow accurate prediction of non-
communicating performance using an AEDM based on the communicating
system test. Thus, DOE will not require at this time that the tested
combination be coil-only in cases where only communicating VSCO
combinations (and no non-communicating VSCO combinations) are
distributed in commerce with a given outdoor unit. However, DOE may
reconsider these decisions in a later rulemaking.
---------------------------------------------------------------------------
\31\ As described in section III.C.2.c, VSCO systems will use at
most two air volume rates, while blower-coil VS systems may have
multiple air volume rates. First, there is an intermediate air
volume rate explicitly anticipated for such systems (see appendix
M1, section 3.1.4.3). Also, as discussed in section III.D.1, DOE is
clarifying that air volume rate may change with outdoor air
temperature.
---------------------------------------------------------------------------
Emerson commented that it agreed with DOE's assessment that less
than 5 percent of variable speed systems are installed as coil-only
configurations today. (Emerson, No. 14 at pp. 1-2) However, Emerson
commented that it believes that two-stage CACs currently have a
similarly small portion of installations in a coil-only configuration,
and elaborated that they believe that energy specifications and test
procedures should be technology-neutral and advocated that all
modulating technology (i.e., two or more stages) should be treated in
the same manner regarding coil-only representation requirements. Id.
Emerson asserted that because of the ability to install VSCO CACs with
a non-communicating thermostat, and because coil-only installation
percentages are similar between variable speed and two-stage CACs, the
coil-only representation requirement should either apply for both
technologies or for neither technology. Id. Emerson provided examples
of variable speed CAC product literature indicating that even for
outdoor units with communicating capability, there are instructions for
installation in a non-communicating setup using a conventional 24V non-
communicating thermostat control.\32\ Id. Emerson also highlighted that
in some cases, the product literature provides instructions for a non-
communicating coil-only installation but shows represented values that
are unclear whether they are derived from a blower-coil pairing or from
the non-communicating coil-only installation.\33\ Id. Emerson
elaborated that this creates the possibility that variable speed
systems are currently being installed in coil-only applications
[[Page 64565]]
for which the system representations may not be representative of
actual performance. Id.
---------------------------------------------------------------------------
\32\ Emerson identified the Bosch BOVB 18 split system heat pump
with ratings as low as 15 SEER (link: https://issuu.com/boschthermotechnology/docs/bosch_ids_family?fr=sYmYyNDIwODA0Mzg) and
the Daikin FTQ series heating and cooling systems, with SEER ratings
from 14.8-16 SEER (link: https://backend.daikincomfort.com/docs/default-source/product-documents/light-commercial/brochures/cb-ftqducted.pdf?sfvrsn=608a2626_20&_ga=2.261207556.887080242.1653602507-1260064005.1653602507&_gl=1*1cbcmhc*_ga*MTI2MDA2NDAwNS4xNjUzNjAyNTA3*_ga_MXJ05EZJZT*MTY1MzYwMjUwNi4xLjEuMTY1MzYwMjU5OS4w).
\33\ Emerson identified the Lennox Elite Series EL18XCV Units
(link: https://tech.lennoxintl.com/C03e7o14l/VIu12Ch2uV/507955-01a.pdf) and the Carrier 24VNA0 Infinity Variable Speed Air
Conditioners with Greenspeed Intelligence (link: https://esmithair.com/wp-content/uploads/2020/02/Air-Conditioners_24VNA0.pdf).
---------------------------------------------------------------------------
In response to Emerson's comments about installation instructions
allowing for installation of non-communicating coil-only installations
for VS systems that presumably are tested on the basis of blower-coil
configurations, DOE notes that 10 CFR 429.16 already requires that
representations be provided for all combinations distributed in
commerce. Hence, representations are required for coil-only
combinations for any VS outdoor unit that is distributed in commerce in
such combinations. The changes in this final rule stipulate that any
such coil-only representation be based on whether the control system
with which it is installed is communicating or non-communicating.
In response to Emerson's comments that coil-only installations are
rare also for two-stage systems, DOE notes that the comments received
on the topic of the default fan power values for low-stage operation
when testing two-stage coil-only systems (see section III.C.1) suggests
otherwise. None of the comments addressed the possibility that a coil-
only configuration may not be representative of two-stage system
installations. Further, the discussion emphasized the trends in motor
technology of furnaces that have shipped in recent years (see, e.g.,
AHRI, No. 25 at p. 3), suggesting that the representative air movers
for two-stage systems will in many cases be existing furnaces rather
than the fans of blower-coils systems. Hence, in this final rule DOE
has not removed the coil-only representation requirement for two-stage
systems or added such a requirement for variable-speed systems.
In summary, manufacturers will be required to represent variable-
speed ACs based on how they distribute them in commerce, which includes
whether they are coil-only communicating, coil-only noncommunicating,
or blower coil, as applicable to a given model of outdoor unit.
3. Space-Constrained Coil-Only CAC Ratings
a. Background
In the March 2022 CAC TP NOPR, DOE discussed the current
requirements for determining represented values of energy efficiency
and capacity for CACs and HPs at Sec. 429.16(a). 87 FR 16830, 16839-
16841. This section specifies that for each model of outdoor unit of a
split-system CAC with single-stage or two-stage compressors,
manufacturers are required to provide represented values based on at
least one coil-only combination that is representative of the least
efficient combination distributed in commerce with that model of
outdoor unit. The requirement to provide coil-only ratings for each
basic model also applies to single split CACs designed for space-
constrained applications (``SC-CAC''). Additional blower-coil ratings
are allowed (i.e., optional) for any applicable individual
combinations, if distributed in commerce. 10 CFR 429.16(a).
DOE also discussed the related waiver requests received from
manufacturers of space-constrained split-system CACs following the
January 2017 CAC TP Final Rule. 87 FR 16830, 16839-16841. DOE received
petitions for test procedure waivers from National Comfort Products
(``NCP''), AeroSys, and First Company related to the represented value
requirements for space-constrained split-system CACs. Id. Each
petitioner claimed that specified basic models of SC-CAC outdoor units
listed in their respective petitions are designed and intended to be
sold only with proprietary blower-coil indoor units equipped with high-
efficiency electronically commutated (``ECM'') fan motors, and not as a
coil-only combination, and therefore requested exemption from the
requirements at 10 CFR 429.16(a)(1) to provide represented values as a
coil-only combination. (NCP, EERE-2017-BT-WAV-0030, No. 1 at p. 1;
AeroSys, EERE-2017-BT-WAV-0042; No. 1 at p. 1; First Co., EERE-2018-BT-
WAV-0012, No. 2 at p. 1) As described in the March 2022 CAC TP NOPR,
DOE denied First Co.'s petition, Aerosys filed for bankruptcy following
DOE's granting them an interim waiver, and DOE granted an interim
waiver applicable for appendix M to NCP on May 15, 2018. 87 FR 16830,
16841.
In the March 2022 CAC TP NOPR, DOE proposed several revisions
related to representation requirements for space-constrained split-
system CACs. 87 FR 16830, 16840-16841. Specifically, DOE proposed to
amend the language in the table found in 10 CFR 429.16(a)(1) to clarify
the rating requirements pertaining to single-split CACs with single-
stage or two-stage compressors.\34\ Id. DOE also tentatively concluded
that measuring the performance of space-constrained systems exclusively
with high-efficiency blower-coil combinations, as requested in waiver
petitions from NCP, AeroSys, and First Co., is not generally
representative of field operation. Id. DOE also noted that because
NCP's waiver petition and the prescribed alternate test procedure are
specific to appendix M, the interim waiver will terminate on the date
on which testing is required under appendix M1 (i.e., January 1, 2023).
Id. DOE therefore did not propose amendments to appendix M1 to
incorporate the interim test procedure waiver granted to NCP, and
requested comment on these proposals. Id.
---------------------------------------------------------------------------
\34\ DOE's proposed clarifications would require every single-
stage and two-stage outdoor unit of single-split CAC to have a
compliant rating with a coil-only combination that is distributed in
commerce and representative of the least efficient combination
distributed in commerce for that particular model of outdoor unit.
---------------------------------------------------------------------------
The Joint Advocates and Lennox supported DOE's proposal to require
coil-only representations for all single- and two-stage single-split
system CACs, including space-constrained systems. (Joint Advocates, No.
18 at p. 3; Lennox, No. 19 at p. 3) Lennox elaborated on their support
by stating that consistency in requirements across similar product
types provides consumers with more information to properly compare
product choices and promotes market fairness.
In contrast with the Joint Advocates and Lennox, AHRI and NCP did
not support DOE's proposal. (AHRI, No. 25 at pp. 2-3; NCP, No. 16 at
pp. 2-10) AHRI and NCP criticized several aspects of DOE's proposal to
require coil-only ratings for space-constrained CACs. Id. In general,
AHRI and NCP critiqued the factual basis underlying DOE's assumptions
that a coil-only rating would be most representative of real-world
performance for space-constrained systems, and asserted that DOE must
amend the test procedure in appendix M1 to incorporate the interim
waiver granted to NCP. (AHRI, No. 25 at p. 3; NCP, No. 16 at p. 2) NCP
also claimed that they would face undue burden from DOE's proposal,
related to sunk design and testing costs and potential redesign costs
they claim would be required to generate a compliant coil-only rating.
(NCP, No. 16 at p. 2) AHRI elaborated by claiming that DOE did not
provide persuasive data to justify not amending appendix M1 to specify
testing of space-constrained split-system CACs in a manner consistent
with NCP's waiver and that the test procedure outlined in the waiver
produces results that more accurately reflect the performance of space-
constrained CAC systems, as opposed to a coil-only rating. (AHRI, No.
25 at p. 3)
b. Applicability of Coil-Only Requirement
In the March 2022 CAC TP NOPR, DOE briefly discussed some of the
reasoning from past documents used to
[[Page 64566]]
support the coil-only representation requirement for spilt-system air
conditioners generally. 87 FR 16830, 16847. DOE also discussed the
applicability of the coil-only requirement for space-constrained CACs,
specifically. 87 FR 16830, 16841. This section provides a more
extensive discussion of the historical context to further support DOE's
position on this matter, in light of comments on this rulemaking as
well as historical assertions from manufacturers of space-constrained
products that the coil-only provisions should not apply to these
products (e.g., see First Co. comments at EERE-2016-BT-TP-0029, No. 21
at p. 2).
The historical application of the coil-only representation
requirement to SC-CACs involves several changes in regulatory
provisions for this type of product, including the provisions for
``Through-the-Wall'' (TTW) product classes of CACs and HPs. In their
waiver petition, and in comments in response to the March 2022 CAC TP
NOPR, NCP refers to their models of space-constrained CACs as ``TTW''
products. However, while the models that were the subjects of the NCP
waiver are physically installed through the exterior wall, the specific
term ``through-the-wall'' no longer has regulatory meaning as a defined
class of products. As explained in the following paragraphs, the TTW
product class expired from DOE definitions in 2010 and is no longer
applicable.
In a May 2002 final rule for energy conservation standards for CACs
and HPs, (``May 2002 CAC ECS Final Rule''), DOE established separate
product classes of SC and TTW product classes. 67 FR 36368, 36406 (May
23, 2002). DOE defined TTW CACs and HPs based on physical
characteristics of the unit (i.e., limitations on cooling capacity and
heat exchanger area), and the installation scenario (i.e., designed to
be installed within a fixed-size opening in an external wall). 10 CFR
430.2. The definition for TTW CACs was also limited to products
manufactured prior to January 23, 2010. Id. In an August 2004
rulemaking for energy conservation standards for CACs and HPs (``August
2004 CAC ECS Final Rule''), DOE elaborated that after January 23, 2010,
the standards for space-constrained products would apply to TTW CACs
and HPs. 69 FR 50997, 50998 (August 17, 2004). In a June 2011 direct
final rule (DFR) regarding energy conservation standards for
residential furnaces and CACs/HPs (``June 2011 Furnaces & CAC ECS
DFR'') DOE discussed the recent expiration of the through-the-wall
product class for CACs. 76 FR 37408, 37446 (June 27, 2011). DOE noted
that the TTW product class expired on January 23, 2010, and
reclassified all TTW products into corresponding classes of space-
constrained CACs. Id. To further illuminate this point, DOE added a
footnote to the energy conservation standards tables at Sec.
430.32(c)(2) to clarify the treatment of TTW product classes. 76 FR
37408, 37546.
The existence of the TTW product class (and subsequent expiration
in 2010) interacts with the coil-only representation requirements
described by DOE in other documents. In an October 2007 test procedure
final rule for CACs (``October 2007 CAC TP Final Rule''), DOE discussed
the required indoor unit combinations for determination of represented
values for CACs and HPs. 72 FR 59906, 59913-59914 (October 10, 2007).
DOE clarified in this rule that for most classes of single-stage,
single-split CACs the highest sales volume indoor unit would be a coil-
only indoor unit, and thus DOE's regulations required that represented
values for these systems be determined based on a coil-only pairing.
Id. DOE included exemptions to the coil-only representation requirement
for certain kinds of single-stage, single-split CACs that would likely
be distributed in commerce only with blower-coil indoor units. Id.
These exempted product classes included mini-splits, multi-splits, and
TTW units. Id. For each of these classes, DOE clarified in the October
2007 CAC TP Final Rule that representations could be based on blower-
coil combinations. Id.
In subsequent documents, DOE re-iterated the coil-only
representation requirement and clarified the applicability to space-
constrained CACs. In a draft guidance document published August 19,
2014 (``2014 CAC Guidance''), DOE stated that split-system CACs with
more than one compressor stage may be tested and rated as a blower-coil
combination only if the condensing unit is sold exclusively with
blower-coil indoor units. EERE-2014-BT-GUID-0033-0001, p. 1. The 2014
CAC Guidance stated that per existing regulations in the CFR, no
provisions existed permitting use of a blower-coil for testing and
rating a split-system central air conditioner where the condenser unit
is also offered for sale with a coil-only indoor unit and that,
furthermore, there was no provision in the CFR permitting the use of a
blower-coil for testing and rating a condensing unit with a single-
speed compressor. Id. Soon thereafter, DOE published a test procedure
final rule pertaining to CACs and HPs (``June 2016 CAC TP Final
Rule''). 81 FR 36992 (June 8, 2016). DOE adopted language that
explicitly required a coil-only representation requirement for single-
split single- and two-stage CACs into its provisions at 10 CFR
429.16(a)(1), which became effective 180 days following the publication
of the final rule (i.e., December 5, 2016). DOE also adopted these
provisions for space-constrained split-system CACs given that they are
subject to the same test procedures and sampling plans as non-space-
constrained single-split air conditioners. 81 FR 36992, 37002. DOE also
adopted provisions at Sec. 429.16(b)(2) requiring that such systems be
tested with ``the model of coil-only indoor unit that is likely to have
the largest volume of retail sales with the particular model of indoor
unit.'' 81 FR 36992, 37050.
In the January 2017 CAC TP Final Rule, DOE kept the same approach
from the June 2016 CAC TP Final Rule requiring that represented values
for one- and two-stage single-split CACs (including space-constrained)
must be determined based on a coil-only value representative of the
least-efficient combination distributed in commerce with that
particular model of outdoor unit. DOE amended the tested combination
requirements to prevent possible conflict between the representation
requirements and the tested combination requirements. Instead of
requiring the ``highest sales volume'' indoor unit in the tested
combination, the January 2017 CAC TP Final Rule required, simply, ``A
model of coil-only indoor unit''. 82 FR 1426, 1470. This clarification
made clear that in all instances, one- and two-stage single-split CACs
(including space-constrained) were required to test and determine
represented values based on a coil-only indoor unit, regardless of
prevalence of retail sales.
In the January 2017 CAC TP Final Rule, DOE also fielded comments
from manufacturers of space-constrained CACs regarding the interplay of
the TTW and space-constrained product classes with the coil-only
representation and testing requirements. 82 FR 1426, 1461-1462. DOE
reiterated that an exclusion for coil-only testing of space-constrained
products was never established, and that manufacturers of space-
constrained products had always been subject to the coil-only rating
requirement, as clarified in the June 2016 CAC TP Final Rule. Id. DOE
also alluded to the expiration of the TTW product class, describing
that the coil-only exclusion for TTW CACs, previously present in 10 CFR
429.16(a)(2)(ii), would not encompass
[[Page 64567]]
the circumstances described by the commenters. Id. DOE reiterated that
while the language being adopted in the January 2017 CAC TP Final Rule
explicitly removed the exclusion from a coil-only testing requirement
for TTW units sold and installed with blower-coil units--it would have
no effect on the ratings procedures for space-constrained units (due
the 2010 expiration of the TTW product class), which are subject to the
same coil-only provisions as for other split system CACs. Id.
In summary, single-split single-stage CACs, including space-
constrained CACs, have historically always been subject to a coil-only
representation requirement, via application of the highest-sales-
volume-combination (HSVC) concept. DOE has, at multiple points, made
this requirement more explicit in the regulatory text but has
consistently held that space-constrained CACs were never excluded from
this requirement. For space-constrained CACs meeting the historical
definition of through-the-wall (TTW) products, DOE has similarly
explained in multiple documents that this product class expired in
January 2010 at which point TTW products were subsumed by the space-
constrained product class, which DOE explained explicitly in the
January 2017 CAC TP Final Rule (82 FR 1426, 1462). Through these facts
it is evident that through-the-wall space-constrained CACs, such as
those identified in NCP's waiver petition, have been subject to the
coil-only rating requirement at least since 2010, and the January 2017
CAC TP Final Rule did not represent the first instance of this
practice.
c. Other Considerations
i. Prevalence of Coil-Only Installations for Space-Constrained CACs
In response to the March 2022 CAC TP NOPR, NCP commented that it
does not manufacture a coil-only indoor unit that may be matched with
the condensing units specified in their waiver, nor do they identify or
offer any other coil-only matched system for distribution in commerce.
(NCP, No. 16 at p.10) Additionally, AHRI and NCP questioned the
representativeness of a coil-only rating for space-constrained
products. Specifically, they both challenged DOE's assumption that the
relative division of coil-only installations applies equally between
typical CAC and space-constrained CAC. (AHRI, No. 25 at p. 2; NCP, No.
16 at pp. 3-5) AHRI asserted that space-constrained CAC systems are
typically installed in multi-family buildings (as opposed to single-
family homes) and claimed that coil-only installations for space-
constrained systems are significantly less common than coil-only
installations for conventional split CACs. (AHRI, No. 25 at p. 2) AHRI
cited DOE's determination that, in 2021, 39% of split-system CAC
installations would be blower-coil indoor units and the remaining 61
percent would be coil-only installations.\35\ Id. AHRI contrasted this
with 2015 RECS microdata showing that for multi-family buildings, only
45 percent of buildings use natural gas or other fuel source for
heating while 55 percent of buildings use electric resistance heating.
Id. DOE interprets AHRI`s comment to imply that space-constrained CACs
are most typically installed in multi-family housing, and multi-family
buildings are predominated by electric heating (which would be
indicative of a blower-coil CAC using electric resistance heating
elements) rather than combustion heating (which would be indicative of
a coil-only CAC paired with a furnace). Therefore, AHRI's comment
implies that space-constrained CACs would be represented more
accurately by a blower-coil combination instead of a coil-only
combination. NCP reiterated the data presented by AHRI and commented
that coil-only installations for space-constrained systems are
uncommon. (NCP, No. 16 at pp. 3-5)
---------------------------------------------------------------------------
\35\ As introduced in section III.D.1.b of this rulemaking, DOE
first discussed its assumptions regarding market penetration rates
for various types of furnace fan motors in the December 2016 CAC ECS
TSD (EERE-2014-BT-STD-0048-0098, page 7-16). These same proportions
were carried through in the analysis proposed in the March 2022 CAC
TP NOPR.
---------------------------------------------------------------------------
DOE notes that although AHRI provided summary data regarding the
heating source for multi-family buildings, neither AHRI nor NCP
provided concrete data showing the relative proportion of coil-only
installations for space-constrained CACs vs coil-only installations for
conventional CACs. DOE finds that AHRI's inference that a higher
proportion of electric heating in multi-family homes does not
constitute sufficient evidence to conclude that the proportion of coil-
only installations for space-constrained systems is lower than the
proportion for conventional systems. With respect to NCP's comment that
they do not manufacture or specify coil-only indoor units to be paired
with their TTW condensing units, DOE notes that the coil-only
representation requirement is equally applicable for all single- and
two-stage split-system CACs. This requirement accounts for the
likelihood that CAC outdoor units may be installed as a coil-only
configuration, even if not specified as such by the outdoor unit
manufacturer. In this manner, the coil-only requirement provides a
conservative estimate of performance that captures the range of likely
installation scenarios for these products. Therefore, DOE concludes
that an approach consistent with the January 2017 CAC TP Final Rule
(i.e., requiring coil-only representations for all single- and two-
stage split system CACs, including space-constrained) provides more
representative measurement of space-constrained system performance. DOE
also acknowledges Lennox's comment stating that by continuing to
require a coil-only representation for all types of split-system CACs,
consumers would have better ability to compare products on the basis of
cost-efficiency tradeoffs. (Lennox, No. 19 at p. 3)
ii. Systems Distributed in Commerce
In the March 2022 CAC TP NOPR, DOE highlighted instances for which
outdoor units designed for space-constrained applications are being
distributed in commerce without a corresponding blower-coil indoor
unit, indicating the potential for pairing a replacement outdoor unit
with an existing indoor unit using a legacy fan that would not likely
be comparable to the ECM fan of the blower-coil indoor unit on which
the system rating is based. 87 FR 16830, 16841. DOE noted that the
cited example is for sale of an NCP outdoor unit, which indicates that
it is impossible to ensure its installation with a blower-coil indoor
unit, as suggested by NCP's waiver petition. Id.
AHRI and NCP challenged DOE's conclusion that NCP's space-
constrained CAC models are distributed in commerce with a coil-only
indoor unit pairing. (AHRI, No. 25 at p. 2; NCP, No. 16 at p. 10) NCP
stated that they do not manufacture a coil-only indoor unit that may be
matched with their space-constrained condensers, nor do they identify
or offer any other coil-only matched system for distribution in
commerce. (NCP, No. 16 at p. 10) NCP also noted that in the case
identified by DOE of an online distributor selling NCP's space-
constrained outdoor units in an unmatched pairing, this was in error
and that NCP quickly took actions to rectify the situation. Id. NCP
demonstrated steps they undertake to ensure that its space-constrained
condenser units are properly sold and marketed as matching pairs with
blower-coil indoor units and offered to provide enhanced documentation
including a product label. Id. NCP concluded by stating that as a small
company, it does not have the appropriate resources to police the
[[Page 64568]]
actions of distributors or installers. (NCP, No. 16 at p. 7) AHRI
offered similar commentary, claiming that DOE made a logical leap by
attributing the actions of a single distributor to actions taken by
NCP, and asserted that the distributor did not follow manufacturer
sales guidelines. (AHRI, No. 25 at p. 2)
Regarding NCP's claim that the example provided by DOE was an
aberration and not representative of their normal distribution
practices, DOE has found additional evidence beyond what was presented
in the NOPR demonstrating that NCP condensers may be distributed in
commerce as unspecified pairings. DOE has found additional listings
from two other distributors advertising NCP condensing units (in fact,
the same units identified in NCP's interim waiver) being sold without a
matched blower-coil indoor unit.\36\ Further, while DOE acknowledges
NCP's status as a small business entity, and the potential difficulties
with policing the activity of distributors, DOE notes that the coil-
only representation requirement for split-system one and two-stage CACs
is designed to capture the range of installations scenarios in which
these systems are likely to be installed. Correspondingly, the coil-
only representation requirement offers a conservative method that
ensures that consumers would be purchasing systems that are compliant
with national standards, even if installed in a coil-only
configuration.
---------------------------------------------------------------------------
\36\ DOE identified the NCPE-418-5010 condensing unit sold as a
standalone unit at both SkipTheWarehouse and on Johnstone Supply,
available online at: https://skipthewarehouse.com/ncpe4185010-15-ton-thru-the-wall-split-system-condensing-unit and https://www.johnstonesupply.com/product-view?pID=B61-354, respectively.
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iii. Interaction With Energy Conservation Standards
Notwithstanding their concerns about the representativeness of
coil-only representations for space-constrained CACs, NCP stated that
they have begun the process of designing and testing modifications to
their space-constrained outdoor units that could allow certifications
with coil-only representations (such as incorporating high-efficiency
DC fan motors, microchannel heat exchangers and/or proprietary
compressor developments), but that these design changes would come at a
considerable cost increase.\37\ (NCP, No. 16 at pp. 5-7) NCP claimed
that they utilize the most efficient components available that are
economically justifiable and asserted that the technical constraints
preventing the certification of its space-constrained condenser units
as a coil-only combination have not changed since they submitted their
original waiver petition. Id. Particularly, NCP highlighted that they
are limited in what they can do to improve the efficiency of the units
due to the dimensional restrictions of the space-constrained
configuration. Id. NCP also provided data showing that even if DOE were
to introduce a lower default fan power coefficient for coil-only CACs
at low-stage operation (as discussed in section III.C.1 of this final
rule), it would still be difficult to meet DOE standards. Id.
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\37\ On August 11, 2022, NCP submitted an enclosure to their
earlier comment that contained new test data and design information.
NCP claimed that they had not yet identified a combination of
components that would allow its TTW condensing units tested with
coil-only indoor units to reach the applicable energy conservation
standards and capacity requirements. NCP reiterated their opinion
that the unacceptable test results were caused by the physical
constraints placed on space-constrained TTW condensing units. (NCP,
No. 26 at p.2) Available online at: https://www.regulations.gov/document/EERE-2021-BT-TP-0030-0026.
---------------------------------------------------------------------------
AHRI and NCP also claimed that DOE's decision at this stage in the
process to terminate and discontinue the test procedure waiver for
appendix M by not incorporating it into the M1 procedure would place
undue burden on NCP, a small manufacturer. (AHRI, No. 25 at p. 2; NCP,
No. 16 at pp. 9-10) AHRI stated that manufacturers have substantially
completed testing according to appendix M1 and that NCP was in the
process of finalizing M1 product designs and preparing for 2023
implementation. (AHRI, No. 25 at p. 2) NCP stated that its space-
constrained condensing units are designed and intended to be paired
with specified air handlers. (NCP, No. 16 at pp. 9-10) NCP elaborated
that due to the new M1 testing procedures they have designed,
prototyped, tested, and begun manufacture of a new air handler, which
they asserted was an arduous, costly undertaking for a small business.
Id. NCP also highlighted the challenges of simultaneously addressing
the pending refrigerant change in 2025, which they asserted would
require replacement of R-410a refrigerants in its outdoor units. Id.
NCP concluded by stating that if DOE continues with the proposed
approach of requiring coil-only representations for space-constrained
systems tested according to appendix M1, it will require redesign of
their space-constrained products (as previously described) and would
substantially increase the burden and cost of testing as well as
resource allocation for NCP. Id.
With respect to NCP and AHRI's arguments regarding the potential
difficulties meeting standards, DOE notes that the stringency of
standards for such TTW products have not changed since Jan 23, 2010
(the date when the TTW product class was subsumed by the space-
constrained product class) and they have been required to meet a 12
SEER standard ever since. The stringency will also not be increasing
for these products in the upcoming 2023 standards, where DOE has
established equivalent-stringency SEER2 standards. Lennox concurred
with DOE's finding that extending the current test procedure waivers
for space-constrained systems is unnecessary, because adequate
standards relief was already provided when DOE maintained the existing
standard levels with no increase in stringency during the previous
energy conservation standards rulemaking. (Lennox, No. 19 at pp. 3-4)
Because DOE did not increase the stringency of standards for space-
constrained systems in the previous ECS rulemaking, manufacturers of
space-constrained systems who were already producing space-constrained
products compliant with standards in terms of SEER and following the
existing representation requirements (i.e., based on a coil-only
rating) \38\ would not incur any costs in order to comply with SEER2
standards based on coil-only ratings. DOE also notes that in their
comment, NCP identified several combinations of coil-only indoor units
that were technologically capable of meeting SEER2 standard levels.
Additionally, the topic of cost/efficiency tradeoffs for space-
constrained systems was discussed in the previous ECS rulemaking, and
are not subject to reevaluation in the context of this rulemaking,
which is limited to the test procedure.
---------------------------------------------------------------------------
\38\ See October 2016 CAC ECS notification of data availability
NODA, where DOE described its provisional translations between SEER
and SEER2 for space-constrained products. DOE conducted a crosswalk
for SC-CACs to account for the increased minimum external static
pressure requirement in appendix M1 which would increase the indoor
fan power consumption. DOE's crosswalk analysis assumed a coil-only
rating as the starting point (i.e., for appendix M measurements),
and a coil-only rating as the end point (i.e., for appendix M1
measurements). 81 FR 74727, 74729-74730.
---------------------------------------------------------------------------
d. Conclusions
As described in preceding sections, DOE has made the following
determinations regarding representation requirements for space-
constrained CACs:
1. Single-split, single-stage CACs, including space-constrained
CACs, have historically always been subject to a
[[Page 64569]]
coil-only representation requirement. DOE has clarified this
requirement at multiple points in the regulatory text, but has
consistently held that space-constrained CACs were never excluded from
this requirement.
2. For space-constrained CACs meeting the historical definition of
through-the-wall (TTW) products, DOE has similarly explained in
multiple documents that this product class expired in January 2010 at
which point TTW products were subsumed by the space-constrained product
class and became subject to the coil-only representation requirement.
3. Based on the best available data, the coil-only representation
requirement for split-system space-constrained CACs is representative
of real-world installations. This determination is supported by the
finding that, despite manufacturer efforts, space-constrained outdoor
units are still being distributed in commerce in a manner consistent
with coil-only installations.
4. Space-constrained systems have been subject to a coil-only
requirement since January 2010, and standards have remained at
equivalent stringency since that time. Manufacturers of space-
constrained systems that have been producing compliant products would
not incur any costs in order to comply with SEER2 standards.
Further, DOE notes that the interim waiver granted to NCP was only
applicable for appendix M, and NCP did not submit any waiver request
applicable to appendix M1. As previously discussed, DOE proposed in the
NOPR not to incorporate into appendix M1 the waiver method granted to
NCP for appendix M. In summary, consistent with its proposals in the
March 2022 CAC TP NOPR DOE is maintaining the requirement that space-
constrained CACs follow the existing representation requirements at 10
CFR 429.16, including the requirement for all one- and two-stage split-
system CACs to develop represented values based on testing with a coil-
only indoor unit representative of the least efficient coil-only indoor
unit distributed in commerce for that basic model.
D. Other Test Procedure Revisions
1. Air Volume Rate Changing With Outdoor Conditions
In the NOPR, DOE explained that requirements for setting air volume
rate in section 3.1.4 of appendix M1 may be in conflict with
instructions to use air volume rates that represent a ``normal
installation'' in section 3.2, particularly for modern blower-coil
systems with multiple-speed or variable-speed indoor fans and control
systems, which may change air volume rate in response to operating
conditions such as outdoor air temperature. 87 FR 16830, 16841. To
address this issue, DOE proposed in the March 2022 CAC TP NOPR to
explicitly state in Step 7 of sections 3.1.4.1.1.a, 3.1.4.2.a, and
3.1.4.3.a that, for blower-coil systems in which the indoor blower
capacity modulation correlates with outdoor dry bulb temperature or
sensible-to-total cooling capacity ratio, use an air volume rate that
represents a normal operation. 87 FR 16830, 16841-16842. Also, DOE
indicated that to ensure consistency of testing, it may be necessary
for manufacturers to certify whether the system varies blower speeds
with outdoor air conditions. However, certification is not being
addressed in this rulemaking and may be addressed in a separate
rulemaking. Id.
In response, Lennox, Rheem and Trane commented that they support
DOE's proposal to add clarifying language to allow fan speed and air
volume adjustments for varying outdoor conditions that are
representative of normal field operation, for blower-coil systems with
multiple-speed or variable-speed indoor fans. (Lennox, No. 19 at p. 4,
Rheem, No. 21 at p. 2, Trane, No. 10 at p. 3) Rheem further commented
that they also support the control system capability to adjust air
volume rate as a function of outdoor air temperature, allowing such air
volume rate variation during testing. (Rheem, No. 21 at pp. 2-3) In
order to make the procedure more representative of field conditions,
Rheem suggested that external static pressure should change in relation
to full stage air flow by using the fan affinity laws, similar to
external static adjustments for multi-stage equipment. Id.
Additionally, Rheem suggested that DOE's proposal to add clarifying
language for blower speed variation should apply to section
3.1.4.4.3.a, instead of section 3.1.4.3.a. Id. Trane pointed out that
they have products that vary the fan speed based on various conditions
such as outdoor ambient and stated that the proposed change is needed
to clear up the discrepancy in procedures. (Trane, No. 10 at p. 3) They
stated that there are several reasons why airflow may be varied from a
nominal setting at different conditions; for example, to optimize
sensible heat ratio and comfort, to maintain consistent heating supply
air temperatures, and to maximize system efficiency. Id.
In response to Rheem's comment about external static adjustments,
DOE believes that the proposed regulatory language already addresses
this factor, in particular the language: ``and calculate the target
minimum external static pressure as described in section 3.1.4.2 of
this appendix,'' which is included in Step 7 where the proposed
revisions were made. The adjustment of external static pressure
described in section 3.1.4.2 specifies that pressure varies as the
square of the air flow, consistent with the fan affinity laws mentioned
by Rheem. Hence, DOE is finalizing the revision without additional
changes in regard to instructions regarding external static pressure.
Also, in response to Rheem, DOE acknowledges that the NOPR preamble
incorrectly cited section 3.1.4.3.a instead of 3.1.4.4.3.a.--the change
was proposed and is finalized in section 3.1.4.4.3.a.
NEEA pointed out that DOE's proposal does not require certification
of the fan speeds that represent ``normal'' operation for the different
test points, and expressed concern that this approach will allow
products to be tested more favorably without confirmation that the
testing represents how products operate in the field. (NEEA, No. 23 at
p. 2) NEEA recommended that DOE verify blower speed variation with a
load-based test procedure using native controls of the system. Id.
As previously stated, certification corresponding to the test
procedure changes are not being addressed in this final rule but may be
considered in a separate rulemaking. Regarding NEEA's recommendation
for a test procedure requiring native controls, DOE notes that this
test procedure rulemaking was initiated as a quick fix of a limited set
of known issues, and that more comprehensive revisions to address
native controls may be considered in a future rulemaking that would
satisfy the 7-year lookback requirements. See further discussion in
section III.B of this document.
Based on the comments received, DOE is finalizing the provisions
regarding variation of indoor air volume rate by adopting the
clarifying language to Step 7 of sections 3.1.4.1.1.a, 3.1.4.2.a, and
3.1.4.4.3.a, as proposed.
2. Wet Bulb Temperature for H4 5 [deg]F Heating Tests
Appendix M1 specifies required and optional heating mode test
conditions for heat pumps, designated as ``H'' conditions. See Tables
11 through 15 of appendix M1. Appendix M1 provides for conducting
optional ``H4'' heating tests at a 5 [deg]F outdoor ambient dry-bulb
temperature and, at a maximum, a 3 [deg]F
[[Page 64570]]
outdoor wet-bulb temperature.\39\ The 3 [deg]F wet bulb condition
represents an extremely dry air condition, which may be difficult to
attain and maintain due to issues with infiltration and ground moisture
passing through the floor in some laboratory setups. Consequently, in
the March 2022 CAC TP NOPR, DOE proposed to amend the wet bulb test
condition for all H4 tests to be 4 [deg]F maximum instead of the
current condition of 3 [deg]F maximum. 87 FR 16830, 16842.
---------------------------------------------------------------------------
\39\ The tests at this condition are optional for heat pumps,
except for Triple-Capacity Northern heat pumps.
---------------------------------------------------------------------------
In response, Carrier, Daikin, Lennox, Nortek, NYSERDA, and Rheem
commented that they all support DOE's proposal to increase the wet bulb
test condition to 4 [deg]F maximum from the 3 [deg]F maximum for H4
tests. (Carrier, No. 15 at p. 1, Daikin, No. 24 at p. 2, Lennox, No. 19
at p. 4, Nortek, No. 13 at p. 3, NYSERDA, No. 17 at p. 2, Rheem, No. 21
at p. 3) Carrier stated that increasing the wet bulb test condition in
the H4 test will reduce the test burden, and Lennox further asserted
that conducting the H4 tests previously in various manufacturer
laboratories has proven to be overly burdensome for the variety of
reasons DOE cites in the CAC TP NOPR at 87 FR 16842. (Carrier, No. 15
at p. 1, Lennox, No. 19 at p. 4) Carrier and Lennox commented that
increasing the maximum wet bulb temperature for the H4 test will
significantly reduce manufacturer test burden. Id. Lennox commented
that this will also help avoid additional capital investments in lab
facilities for specialized equipment to attain the wet bulb requirement
of 3 [deg]F and this relief will allow more test facilities to be
capable of validating performance at low ambient conditions while
maintaining sufficiently low humidity conditions to provide reasonable
test results. (Lennox, No. 19 at p. 4) Nortek also commented that
increasing the wet bulb temperature on the H4 test from 3 [deg]F to 4
[deg]F will reduce their test burden by reducing the time required to
remove moisture in achieving the wet bulb temperature test point.
(Nortek, No. 13 at p. 3) NYSERDA commented that the proposed amendment
of the wet bulb temperature conditions for the H4, H42, or
H43 heating tests to a 4 [deg]F maximum temperature will
make the current optional cold temperature test easier to reliably
replicate and should improve understanding of system performance at
cold temperatures for more basic models being distributed in commerce.
(NYSERDA, No. 17 at p. 2)
Based on the discussion presented in the March 2022 CAC TP NOPR and
given the general support of the proposals by commenters, DOE is
finalizing its amendment and increasing the wet bulb test condition to
a maximum of 4 [deg]F for H4 tests.
3. Hierarchy of Manufacturer Installation Instructions
Instructions for installation of CAC/HP products can take multiple
forms, including documents shipped with the product, labels affixed to
the outdoor unit and/or indoor unit, and online documents.
Section 2(A) of appendix M1 provides requirements regarding the
installation instructions to be used and their order of precedence
(i.e., installation instruction hierarchy) for variable refrigerant
flow (``VRF'') multi-split systems. Section 2(A) specifies that
installation instructions that appear in the labels applied to the unit
take precedence over installation instructions that are shipped with
the unit. Further, Section 2(A) specifies that the term
``manufacturer's installation instructions'' does not include online
manuals. Appendix M1 does not specify installation instruction
hierarchy for any other types of CAC/HP products.
Throughout appendix M1, references to manufacturer's installation
instructions are made regarding refrigerant charging requirements
(section 2.2.5), installation of an air supply plenum adapter accessory
for testing small-duct, high-velocity systems (section 2.4.1.c), and
control circuit connections between the furnace and the outdoor unit
for coil-only systems (section 3.13.1.a).
DOE notes that it initially proposed in a supplemental NOPR
published November 9, 2015 (``November 2015 SNOPR'') that the hierarchy
of installation instructions be located in proposed section 2.2.5.1 of
appendix M1, which pertains to refrigerant charging requirements. See
80 FR 69278, 69350.\40\ However, as finalized in the June 2016 CAC TP
Final Rule, the installation instruction hierarchy provision was
located within section 2(A) of appendix M1, and therefore applies only
to testing of VRF multi-split systems. 81 FR 36992, 37060. The June
2016 CAC TP Final Rule did not provide a discussion of this change.
---------------------------------------------------------------------------
\40\ DOE also notes that as initially proposed, installation
instructions that are shipped with the unit were to take precedence
over installation instructions that appear in the labels applied to
the unit, but this hierarchy was reversed in the final rule. 81 FR
36992, 37060.
---------------------------------------------------------------------------
The requirements regarding installation instruction would be
equally applicable to classes of CAC/HP other than VRF multi-split
systems. As noted, manufacturer's installation instructions are
referenced in a number of provisions in appendix M1. Therefore, in the
March 2022 CAC TP NOPR, DOE proposed to add in section 2(B) of appendix
M1, ``Testing Overview and Conditions for Systems Other than VRF,'' the
same requirements associated with installation instructions that are in
section 2(A), i.e., what instructions can be used and what instructions
take precedence. 87 FR 16830, 16842. Doe noted that this proposal would
align the approach for all classes of CAC/HP with the current approach
for VRF CAC. Id.
Lennox and Rheem commented that they support DOE's proposal for
aligning the approach regarding installation instruction precedence for
all classes of CAC/HP with the current approach of VRF AC. (Lennox, No.
19 at p. 4, Rheem, No. 21 at p. 3) Rheem further suggested that for
clarity in the final rule, DOE should clearly specify whether a sticker
on the unit takes precedence over installation instructions,
particularly where use of the installation instructions is referenced
in the appendix M1 test procedure (Rheem, No. 21 at p. 3).
Additionally, Rheem stated that DOE also specifies a Section 2(B) will
be added to appendix M1 to 10 CFR part 430. Rheem points out that
Section 2(B) already exists in the test procedure, and therefore DOE
should add a section 2(C) to capture these changes.\41\ Id.
---------------------------------------------------------------------------
\41\ In the May 2022 CAC TP NOPR, DOE had stated that they will
add instructions to the already existing Section 2(B), and not that
a new section is needed. Hence, DOE will not add a Section 2(C), as
suggested by Rheem.
---------------------------------------------------------------------------
In response to Rheem's comment regarding addition of section 2(B)
of appendix M1, DOE notes that it indicated that the additional
requirements regarding installation instructions would be inserted ``in
section 2(B),'' not that a new section 2(B) would be added. In response
to the comment about clarifying whether a sticker on the unit takes
precedence over installation instructions, DOE believes that the
language proposed for section 2(B), ``Installation instructions that
appear in the labels applied to the unit shall take precedence over
installation instructions that come packaged with the unit,''
sufficiently clarifies this point. Specifically, ``installation
instructions'' does extend to installation instructions that appear on
the labels applied to the unit, and that such installation instructions
take precedence over installation instructions that are not applied to
the unit.
[[Page 64571]]
Trane commented that even though they agreed with hierarchy
proposed by DOE, they raised a concern that that some combinations of
indoor units require unique charging instructions, as opposed to the
typical instructions, i.e., subcooling target, listed on outdoor unit
labels. (Trane, No. 10 at p. 3) They cited the variations of indoor
internal coil volume with various matched pairs as the reason for this.
Hence, Trane suggested that outdoor nameplates should have a footnote
referring the installer to the indoor product instructions for any
exception, unless otherwise noted. Id.
In response to Trane's comment, DOE agrees that there may be
circumstances in which the very different design details of multiple
indoor units paired with the same outdoor unit could affect the optimum
installation approach. In such cases, the manufacturer has the
discretion to indicate in the outdoor unit installation instructions
that specific instructions provided with indoor units be followed. Such
an approach would not be contrary to the established precedence of the
outdoor unit's installation instructions and would not be contrary to
the proposed appendix M1 requirements, as long as the instructions used
are not online instructions. DOE does not believe that appendix M1
should be modified to specifically explain this possibility.
Hence, DOE is adding the installation instruction hierarchy to
appendix M1 section 2(B) as proposed.
4. Adjusting Airflow Measurement Apparatus To Achieve Desired SCFM at
Part-Load Conditions
Sections 3.1.4.1.1, 3.1.4.2, and 3.1.4.4.3 of appendix M1 each
specify seven steps for achieving the correct air volume rate to be
used for testing (cooling full-load air volume rate, cooling minimum
air volume rate, and heating full-load air volume rate, respectively).
Each of these sections indicates that the measured air volume rate when
adjustments are complete should be used for all tests that call for the
same nominal air volume rate, i.e., cooling full-load, cooling minimum,
or heating full-load air volume rate, using the final fan speed or
control settings. However, when operating at different test conditions,
differences in air density and/or loading of condensate on the indoor
coil may lead to different measured air volume rates.\42\ None of the
section 3.1.4.1.1, 3.1.4.2, or 3.1.4.4.3 of appendix M1 indicate what
adjustments are allowed or required to obtain the same air volume rate
for different operating conditions. In order to clarify how to achieve
the same air volume rates for different operating conditions, DOE
proposed to explicitly require that the airflow measurement apparatus
fan be adjusted if needed to maintain a constant air volume rate for
all tests using the same nominal air volume rate. Similarly, the
section would explicitly state that the speed and settings of the fan
of the unit under test are not to be adjusted. 87 FR 16830, 16843
(March 24, 2022).
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\42\ When operating in cooling mode, water vapor in the return
air may condense and collect and flow down the coil into the indoor
unit's drain pan. This removal of water vapor is called
dehumidification--it occurs only in cooling mode and its magnitude
depends on the test conditions.
---------------------------------------------------------------------------
In response, Lennox commented that they support DOE's proposals to
add more specific direction to step 7 of sections 3.1.4.1.1, 3.1.4.2,
and 3.1.4.4.3, as proposed. (Lennox, No.19 at p.4) Rheem commented that
although they agree that the proposed changes may assist in the
repeatability of certification tests, they disagree that DOE's
proposals would be more representative than the current test procedure.
(Rheem, No. 21 at p. 3) Rheem stated that once a ducted CAC/HP is
installed in a consumer's home, the airflow and external static
pressure will change with conditions, as reflected in the current test
procedure. Id. Rheem noted that in the discussion under III.C.1 of the
NOPR, DOE proposed to allow the air volume rate to change if the native
controls of the system modulate indoor blower capacity. Rheem
recommended that DOE add language to clarify that this allowance to
adjust the airflow measurement apparatus only applies to systems that
do not modulate indoor blower capacity. Id.
DOE does not agree with Rheem's comment suggesting that the current
test procedure does not allow adjustment of the airflow measurement
apparatus fan. Specifically, the words, ``use the final speed or
control settings'' is not clear regarding whether this applies to the
unit under test, the code tester, or both. DOE notes that by not
specifically precluding adjustment of the code tester fan, the current
Federal test procedure does not fully specify the allowable fan
adjustments, leaving open the possibility for clarification.
In response to Rheem's comment regarding clarifying language, DOE
notes that the proposed additions indicate that the final indoor fan
speed or control settings of the unit under test must be used for all
tests that use the same nominal air volume rate (e.g., cooling full-
load air volume rate), and that the fan of the airflow measurement
apparatus should be adjusted if needed to obtain the same air volume
rate (in scfm), unless the system modulates the indoor blower speed for
different outdoor conditions or to adjust the sensible to total heat
ratio. DOE considers this text is sufficiently clear that the
instructions apply to systems that do not modulate indoor blower
capacity. Further, DOE points out that adjustment of the airflow
measurement apparatus would very likely be required for systems that do
modulate the indoor blower capacity, to maintain the relationship
between air volume rate and external static pressure, as required by
section 3.1.4.2 of appendix M1.
Hence, DOE is finalizing the changes to step 7 of the requirements
for setting air volume rate as proposed.
5. Revision of Equations Representing Full-Speed Variable-Speed Heat
Pump Operation at and Above 45 [deg]F Ambient Temperature
In a variable speed system, the compressor's actual speed at its
full-load condition may change as the outdoor temperature changes.
While the compressor speed at full speed may differ at different
outdoor temperatures, accuracy of predictions using the test results
from two temperature conditions to calculate the performance for a
third temperature condition is maximized when the same compressor speed
is used for the tests at the two different ambient temperature
conditions (see, e.g., 81 FR 58164, 58178 (August 24, 2016)).
For calculation of full-speed compressor heating mode performance
in the temperature ranges less than 17 [deg]F and greater than or equal
to 45 [deg]F, the test procedure determines performance based on the
H32 and H12 tests, which are conducted at 17
[deg]F and 47 [deg]F, respectively (see appendix M1, sections 4.2.4.c,
which refers to equations 4.2.2-3 and 4.2.2-4 in Section 4.2.2). As
indicated in appendix M1 in the Table 14 footnotes, the H12
test is run with the compressor speed that represents normal operation
at 17 [deg]F conditions. However, for many variable-speed heat pumps,
this is a higher compressor speed than would be normal for operation at
47 [deg]F conditions.
The H1N test represents normal 47 [deg]F operation, as
indicated in the Table 14 footnotes. For heat pumps with different
normal speeds for 17 [deg]F and 47 [deg]F conditions, the full-speed
compressor performance equation is not appropriately representative for
temperatures greater than or equal to 45 [deg]F. For example, at 47
[deg]F, the equation would indicate that the capacity is equal to the
H12 capacity, even though the H1N test is
specifically intended to represent capacity at 47 [deg]F. To rectify
[[Page 64572]]
this issue, DOE proposed in the March 2022 CAC TP NOPR to amend the
portion of the equations representing performance in conditions warmer
than 45 [deg]F. 87 FR 16830, 16843. Specifically, DOE proposed that the
capacity equation for this temperature range would be multiplied by the
ratio of the capacities of the H1N and H12 tests.
Id. Similarly, DOE proposed that the power input equation for this
range would be multiplied by the ratio of the power inputs measured in
the H1N and H12 tests. Id. DOE noted that this
would change the calculated capacity and power input for the range of
temperature above 45 [deg]F to be consistent with the compressor speed
of the H1N test (which is intended to represent performance
in this range), rather than with the compressor speed of the
H32 test, which is conducted in a 17 [deg]F ambient
temperature. Id.
In response, Lennox supported DOE's proposed change to the full-
capacity performance equations for variable speed heat pumps in the
ambient temperature range above 45 [deg]F. (Lennox, No. 19 at p. 5)
Rheem recommended that DOE does not make the proposed changes. (Rheem,
No. 21 at p. 4) Rheem contended that the proposal to modify the
capacity and power equations above 45 [deg]F would not have significant
effect on heat pump HSPF2 calculations, since variable speed
applications would likely operate in low stage during low building load
conditions. Rheem questioned the value of adding complexity to variable
speed HSPF2 calculations if the change will not have meaningful effect
on the results and recommends that DOE not change the current
calculation method for HSPF2 of variable speed heat pumps. (Rheem, No.
21 at pp. 3-4) DOE considers that the proposed calculation changes
(i.e., applying a simple ratio coefficient) does not represent any
significant increase in complexity compared to the overall scale of
test procedure calculations and that it is important to provide for a
more accurate calculation of HSPF2, even if the impact on the
calculated HSPF2 value is minimal. Therefore, DOE is finalizing its
proposed approach in this final rule.
6. Calculations for Triple-Capacity Northern Heat Pumps
Section 4.2.6 of appendix M1 includes additional steps for
calculating HSPF2 of a heat pump having a triple-capacity compressor.
Heat pumps with triple-capacity compressors respond to building heating
load by operating at low (k=1), high (k=2), or booster (k=3) capacity
or by cycling on and off at one or more of those stages. Section
4.2.6.5 covers the scenario where the heat pump alternates between high
(k=2) and booster (k=3) compressor capacity to satisfy the building
load. In this scenario, the total electrical power consumption is
determined by calculating the fraction of time the system spends
operating in the high and booster stage, respectively, and then
weighting the steady-state power consumption at each operating state
accordingly. Section 4.2.6.5 gives equations for calculating the
fraction of load addressed by the high compressor stage, denoted as
``X\k=2\(Tj)'', as well as the fraction of load addressed by
the booster compressor stage ``X\k=3\(Tj)''. These
proportions should, by definition, be complementary because the system
is either operating in high compressor stage or boost compressor stage.
However, the equation for the booster capacity load factor
``X\k=3\(Tj)'' is erroneously set equal to the high-capacity
load factor ``X\k=2\(Tj)'' as opposed to the complementary
value ``1 X\k=2\(Tj).'' Therefore, DOE proposed to correct
the booster capacity load factor equation to be defined as
X\k=3\(Tj) = 1-X\k=2\(Tj). DOE did not receive
any comments in response to its proposal, and is therefore finalizing
its proposed approach in this final rule.
7. Heating Nominal Air Volume Rate for Variable-Speed Heat Pumps
Appendix M1 includes procedures for calculating the heating
capacity and power input for variable-speed heat pumps at various test
conditions. The H1N test is used to calculate the nominal
heating capacity of the system at 47 [deg]F ambient temperature,
whereas the H12 test is used to calculate maximum heating
capacity at 47 [deg]F and the H11 test is used to calculate
minimum heating capacity at 47 [deg]F. Section 3.1.4.7 of appendix M1
requires that manufacturers must specify a heating nominal air volume
rate for each variable-speed heat pump system and must provide
instructions for setting the fan speed or controls. The heating full-
load air volume rate is defined in section 3.1.4.4 of appendix M1,
which ties the heating full-load air volume rate to the cooling full-
load air volume rate and denotes static pressure requirements. However,
in Table 14 to appendix M1 (which specifies heating mode test
conditions for units having a variable-speed compressor), the
H1N test (used for calculating nominal heating capacity at
47 [deg]F) is erroneously specified as using the ``Heating Full-load''
air volume rate instead of the heating nominal air volume rate. Because
the H1N test is intended to represent nominal heating
capacity, DOE is amending Table 14 to specify the ``heating nominal air
volume rate'' as defined in section 3.1.4.7 of appendix M1 as opposed
to the ``heating full-load air volume rate''. As discussed in section
III.C.2 of this final rule, DOE is also amending the test provisions
for variable-speed compressor systems with coil-only indoor units. The
amendments mentioned in this section only apply to variable-speed
systems equipped with blower-coil indoor units, while variable-speed
coil-only systems would be required to test using the heating full-load
air volume rate at the H1N test condition.
DOE did not receive any comments in response to this issue in the
March 2022 CAC TP NOPR and is finalizing its proposal to specify
heating nominal air volume rate as the air volume rate to be used for
the H1N heating test for variable-speed heat pumps.
8. Clarifications for HSPF2 Calculation
Section 4.2 of appendix M1 contains methodologies for calculating
HSPF2 for all heat pumps. DOE has identified an instance where
additional instruction may be warranted to make clear the calculation
procedures across different types of heat pump systems. In the March
2022 CAC TP NOPR, DOE proposed to clarify the appropriate slope
adjustment factor to be used in the calculation for building heating
load (Equation 4.2-2). 87 FR 16830, 16844.
As written, Equation 4.2-2 refers to the heating load line slope
adjustment factor ``C'', which varies by climate region according to
Table 20. However, Table 20 includes both the ``C'' factor as well as a
factor denoted ``CVS''--the variable-speed slope factor,
which includes different coefficients that impact calculation of HSPF2.
CVS is not explicitly referenced in the definitions
surrounding Equation 4.2-2, therefore DOE proposed to amend the
language of that paragraph to indicate that the slope adjustment factor
``C'' should be used when calculating building heating load except for
variable-speed compressor systems, where the variable-speed slope
adjustment factor ``CVS'' should be used instead. Id.
DOE did not receive any comments regarding this proposal and is
thus adopting its proposal to clarify the calculation process for
heating load line slope factor as it pertains to variable-speed heat
pumps.
9. Distinguishing Central Air Conditioners and Heat Pumps From
Commercial Equipment
EPCA defines ``industrial equipment'' as equipment of a type which,
among other requirements, is not a covered product under section
6291(a)(2), i.e.,
[[Page 64573]]
not a covered consumer product. (42 U.S.C.6311(2)(A)) Small, large, and
very large commercial package air conditioning and heating equipment
are included as types of covered industrial equipment. (42
U.S.C.6311(1)(B,C,D))
EPCA defines ``central air conditioner'' as a product, other than a
packaged terminal air conditioner, which is powered by single phase
electric current, is air-cooled, is rated below 65,000 Btu per hour, is
not contained within the same cabinet as a furnace the rated capacity
of which is above 225,000 Btu per hour and is a heat pump or a cooling
only unit. (42 U.S.C. 6291(21)) DOE understands that there are basic
models on the market that meet the central air conditioner definition
but are exclusively distributed in commerce for commercial and
industrial applications. In DOE's view, there are certain types of
equipment that meet the EPCA definition of CAC but that EPCA did not
intend for DOE to regulate as consumer products. To clarify that any
such model is not a central air conditioner, DOE proposed in the March
2022 CAC TP NOPR to revise the central air conditioner definition so
that it explicitly excludes these equipment categories, similar to the
way the original EPCA definition excludes packaged terminal air
conditioners and packaged terminal heat pumps. The exclusion for
single-package vertical air-conditioners and heat pumps would refer
specifically to those models that could be confused with central air
conditioners, i.e., those that are single-phase with capacity less than
65,000 Btu/h, for which the test procedure notice of proposed
rulemaking for single-package vertical air conditioners and heat pumps
has proposed new definitions. 87 FR 2490, 2518 (January 14, 2022).
DOE emphasizes that the exclusion from the central air conditioner
definition for a given model depends on whether it meets the definition
for one of the excluded categories. For example, a model must meet the
packaged terminal air conditioner definition in 10 CFR 431.92 to be
considered to be a packaged terminal air conditioner. If such a model
had both characteristics listed in the central air conditioner
definition and similarities to packaged terminal air conditioners, but
was not ``intended for mounting through the wall,'' it would be missing
a key characteristic of the packaged terminal air conditioner
definition. Unless it met the definition for one of the other
categories proposed to be excluded, it would be considered a central
air conditioner and covered under the applicable standards and test
procedures in part 430 irrespective of whether it gets installed in a
consumer or commercial building.
DOE did not receive any comments in response to its proposed
clarification of the definition of central air conditioners and heat
pumps at 10 CFR 430.2 to exclude other similar product categories for
consideration of coverage. Therefore, DOE is finalizing its proposals
from the NOPR without amendment in this final rule.
10. Additional Test Procedure Revisions
On May 8, 2019, AHRI submitted a comment responding to the notice
of proposed rulemaking to revise and adopt procedures, interpretations,
and policies for consideration of new or revised energy conservation
standards (2020 Process Rule NOPR, 84 FR 3910, Feb. 13, 2019). The
comment included as Exhibit 2 a ``List of Errors Found in appendix M
and appendix M1'' (``AHRI Exhibit 2''). (EERE-2017-BT-STD-0062-0117 at
pp. 23-24) Many of the errors pointed out by AHRI regard typographical
errors in appendices M and M1. DOE published a correcting amendment to
appendices M and M1 on December 2, 2021 (``December 2021 Correcting
Amendment''). 86 FR 68389. The December 2021 Correcting Amendment
addressed some of the ``Errors'' identified in AHRI Exhibit 2, but not
all of them. In the March 2022 CAC TP NOPR, DOE proposed to address
additional ``Errors'' identified in AHRI Exhibit 2, discussed in the
following sections to improve accuracy and representativeness of the
test procedures. 87 FR 16830, 16845.
a. Revisions Specific to Appendix M
AHRI's comment identified three areas of appendix M where they
requested changes. (AHRI Exhibit 2, EERE-2017-BT-STD-0062-0117 at pp.
23-24) These are detailed in Table III-4. Additionally, DOE identified
one transcription error in the December 2021 Correcting Amendment
related to changes made in section 3.6.4 of appendix M. DOE is making
corresponding revisions in this final rule to correct that
transcription error.
Table III-4--AHRI-Identified Errors to Appendix M
----------------------------------------------------------------------------------------------------------------
Original appendix M Proposed change in the
Section language AHRI comment summary March 2022 CAC TP NOPR
----------------------------------------------------------------------------------------------------------------
1.2.............................. Nominal cooling capacity The H1N test is required Remove the ``Optional
is approximate to the in section 3.6.4, and H1N test'' and replace
air conditioner cooling section 3.6.4 the ``H12'' with
capacity tested at A or designates the H1N ``H1N''
A2 condition. Nominal test--not the H12 test.
heating capacity is
approximate to the heat
pump heating capacity
tested in H12 test (or
the optional H1N test).
4.1.4.2.......................... A = EER \k=1\(T) - B * T - The EER\k=1\(Tj) should Revise the formula to
C * T2\2\. be EER\k=2\(Tj) because implement this change
the coefficient ``A'' to EER\k=2\(Tj).
only utilizes the
maximum speed
temperature, T2.
4.2.c............................ For a variable-speed heat 2017 and later versions Accurately implement the
pump, Qh\k\(47) = of appendix M use change intended by the
Qh\k=N\(47), the space H\k=2\calc for all December 2021
heating capacity conditions, as Correcting Amendment.
determined from the H1N explained in 3.6.4.
test. This should not be an
exception for the rest
of the calculations.
----------------------------------------------------------------------------------------------------------------
The following sections discuss changes to the language of appendix
M that DOE believes will improve clarity regarding how tests and
calculations are to be conducted to determine capacity levels and
efficiency metrics to address the topics identified in AHRI's comment.
i. Definition of Nominal Capacity
AHRI commented that the description of nominal heating capacity
within the definition for ``nominal capacity'' in
[[Page 64574]]
section 1.2 of appendix M incorrectly references the H1N
test as ``optional.'' AHRI claimed that, on the contrary, the
H1N test is required for heat pumps. (AHRI Exhibit 2, EERE-
2017-BT-STD-0062-0117 at pp. 23-24) DOE agrees with the AHRI comment,
since section 3.6.4, ``Tests for a Heat Pump Having a Variable-Speed
Compressor,'' requires the H1N test. Therefore, DOE proposed
in the March 2022 CAC TP NOPR to revise the definition of ``nominal
capacity'' to remove the references to the H12 test in its
entirety to avoid confusion. 87 FR 16830, 16845.
In response to the NOPR proposal, the CA IOUs commented that by
making this reference to the H1N test, DOE is making the
definition inapplicable to systems with single-speed and two-capacity
compressors. (CA IOUs, No. 20 at pp.1-2) The CA IOUs proposed the
following definition, so that it may be applicable to single-stage and
two-stage heat pumps (additions in italics, deletions in [brackets]):
Nominal capacity means ``the capacity that is claimed by the
manufacturer on the product name plate. Nominal cooling capacity is
approximate to the air conditioner cooling capacity tested at A or
A2 condition. Nominal heating capacity is approximate to the
heat pump heating capacity tested in the H1 or H12 test for
units that have a single-speed compressor, the H12 test for units that
have a two-capacity compressor or are a triple-capacity northern heat
pump,\43\ or [(or the optional H1N test).] the H1N test for
units that have a variable-speed compressor.'' Id.
---------------------------------------------------------------------------
\43\ Appendix M1, section 1.2, defines ``triple-capacity,
northern heat pump'' as a heat pump that provides two stages of
cooling and three stages of heating. The two common stages for both
the cooling and heating modes are the low-capacity stage and the
high-capacity stage. The additional heating mode stage is the
booster capacity stage, which offers the highest heating capacity
output for a given set of ambient operating conditions.
---------------------------------------------------------------------------
DOE notes that the term nominal heating capacity is only used to
specify the heating capacity for the H1N test for variable-
speed systems. Additionally, the term nominal capacity is not required
for certification of CAC/HPs. Hence, DOE is not revising the definition
as suggested by the CA IOUs and DOE is instead finalizing the
definition as proposed in the March 2022 CAC TP NOPR.
ii. Revising Energy Efficiency Ratio Equation at Intermediate
Compressor Speed
In section 4.1.4.2 of appendix M, there are a series of equations
used to calculate EERk=i(Tj), the steady-state
energy efficiency ratio of the test unit when operating at an
intermediate compressor speed (k=i) for outdoor temperature
Tj. This value is calculated using a quadratic equation:
EERk=i(Tj) = A + B*Tj +
C*Tj\2\. These coefficients (A, B and C) are calculated by
their own respective formulae.
AHRI commented that the formula for the ``A'' coefficient has an
error. Specifically, EERk=1(T2) in the equation
should be EERk=2(T2) because the coefficient
``A'' only utilizes maximum-speed temperature T2. (AHRI
Exhibit 2, EERE-2017-BT-STD-0062-0117 at pp. 23-24) In the March 2022
CAC TP NOPR, DOE proposed to revise this calculation such that it uses
the intended ``k=2''. 87 FR 16830, 16845. The use of ``k=2'' is
supported both by its appearance in ASHRAE 116-2010, ``Methods for
Testing for Rating Seasonal Efficiency of Unitary Air Conditioners and
Heat Pumps'' (see page 25), and also in the DOE test procedure final
rule that first established test methods for variable-speed systems. 49
FR 8304, 8316 (March 14, 1987).
DOE did not receive any comments in response to this proposed
correction and is therefore finalizing its proposed approach in this
final rule.
iii. Clarification of Compressor Speed Limits in Heating Tests for Heat
Pumps Having a Variable-Speed Compressor
In the December 2021 Correcting Amendment, DOE discussed
corrections to the compressor speed limitations for the H1N
heating mode test for both appendices M and M1. 86 FR 68389, 68390.
However, when setting out the correcting language in the amendatory
instruction for appendix M, the instructions erroneously directed to
revise the fifth sentence of paragraph a. to section 3.6.4, when the
instructions were intended to revise the seventh sentence of the same
paragraph. As currently printed, the text in paragraph a. of section
3.6.4 to appendix M includes two sentences starting with ``for a
cooling/heating heat pump . . .'' that give conflicting instructions.
Accordingly, DOE proposed in the March 2022 CAC TP NOPR to revise this
paragraph to reflect the intent of the December 2021 Correcting
Amendment and, by extension, the January 2017 CAC TP Final Rule. 87 FR
16830, 16845. DOE did not receive any comments and is therefore
finalizing as proposed.
b. Revisions Specific to Appendix M1
AHRI's comment identified one area of appendix M1 where they
requested a change. (``AHRI Exhibit 2,'' EERE-2017-BT-STD-0062-0117 at
p. 23) This requested change is detailed in Table III-5.
Table III-5--AHRI-Identified Errors to Appendix M1
----------------------------------------------------------------------------------------------------------------
Proposed change in the March
Section Original appendix M1 language AHRI comment summary 2022 CAC TP NOPR
----------------------------------------------------------------------------------------------------------------
4.2............... Qh(47 [deg]F): the heating For variable speed heat Revise the language to be
capacity at 47 [deg]F pumps, the language should clearer about what capacity
determined from the H2 H12or be clarified to H\k=2\calc. to use for different types
H1N test, Btu/h. of heating-only heat pumps.
----------------------------------------------------------------------------------------------------------------
The following sections discuss amendments to the language of
appendix M1 that DOE believes will improve clarity regarding how tests
and calculations are to be conducted to determine capacity levels and
efficiency metrics to address the topic identified in AHRI's comment,
additional topics in comments from interested parties, and other areas
for improvement identified by DOE.
i. Detailed Descriptions of Capacity for Different Subcategories
AHRI commented that in Section 4.2 of appendix M1, which describes
the calculation for HSPF2 for different subcategories of heat pumps,
there is a lack of clarity in the term for heating capacity measured at
47 [deg]F, ``Qh(47 [deg]F),'' in Equation 2-2, the building
load, ``BL(Tj),'' equation. (``AHRI Exhibit 2,'' EERE-2017-
BT-STD-0062-0117 at p. 23) Currently, the description of
Qh(47 [deg]F) says that it is ``determined from the H,
H12 or H1N test.'' Additionally, the first ``H''
is missing an additional character to specify the appropriate test
point. DOE agrees with
[[Page 64575]]
AHRI's assessment of this description, and DOE proposed in the March
2022 CAC TP NOPR to revise this description to include specific
instructions for which test point is appropriate for different heat
pump subcategories. DOE proposed to specify that the H1 test is for a
heat pump with a single-speed compressor, the H12 test is
for a heat pump with a two-speed compressor, and the H1N
test is for a heat pump with a variable-speed compressor. 87 FR 16830,
16846.
DOE did not receive any comments in response to its proposed
clarifications and is thus finalizing as proposed in this rule. DOE
notes that AHRI Exhibit 2 used a ``H\k=2\calc'' term that
does not exist in the referenced section of appendix M1. While DOE is
revising this section to add clarity in light of AHRI's general
comment, DOE will not be proposing to make the exact edit proposed by
AHRI.
ii. Heating Building Load Line for Regions Other Than IV
Trane commented that the denominator in equation 4.2-2, the
building heating load, ``BL(Tj),'' equation, the expression
``Tzl-5 [deg]F'' should be replaced with ``Tzl-
TOD''. (Trane, No. 10 at p. 2) Trane asserted that they made
this recommendation based on previous DOE rulemakings, including the
August 2016 SNOPR for the 2017 appendix M1 rule (81 FR 58164 and 82 FR
1426, respectively). They stated that when the building load is
calculated for regions other than Region IV, then using 5 [deg]F
instead of the specific region's TOD would result in
incorrect calculation of HSPF2. Id.
In the January 2017 CAC TP Final Rule, DOE stated that the
appearance of TOD instead of 5 [deg]F in the denominator of
equation 4.2-2 was a mistake, that first appeared in the November 2015
SNOPR.\44\ 82 FR 1426, 1454. Therefore, DOE will not be making the
change to equation 4.2-2 as suggested by Trane, and the denominator
shall remain as ``Tzl-5 [deg]F''.
---------------------------------------------------------------------------
\44\ Bruce Harley Energy Consulting (BHEC) provided some field
monitoring data and analysis of heating loads conducted at the
request of PG&E, for seven homes covering regions I/II, IV and V.
The initial comparison of regional heating load lines with the load
lines determined for the seven monitored locations led to the
conclusion that equation 4.2.2 in the August 2016 SNOPR incorrectly
included the term TOD. (BHEC, No. 28 at pp. 3-6)
---------------------------------------------------------------------------
iv. Low-Static Ducted Blower-Coil Test Procedures
In response to the March 2022 CAC TP NOPR, AHRI and Samsung
commented that currently, appendix M1 does not allow testing of Low
Static Single Zone units, and requested that the definition of a low-
static blower-coil system be expanded to include some products that
cannot accommodate the 0.5 inches w.c. necessary for testing. (AHRI,
No. 25 at p. 7, Samsung, No. 22 at pp. 2-3) They suggested the
following revised version of the current definition in section 1.2 of
10 CFR part 430, appendix M1 (commenters' additions in italics):
Low static blower-coil system means, (a) A ducted multi split or
multi head mini split system for which the indoor unit produce greater
than 0.01 inches w.c. and a maximum of 0.35 inches w.c. external static
pressure when operated at the cooling full load air volume rate not
exceeding 400 cfm per rated ton of cooling, or (b) A ducted single zone
mini split for which the indoor unit produces a maximum of 0.25 inches
w.c. external static pressure not exceeding 350 cfm/ton when operated
at the highest possible air flow rate and has a rated heating or
cooling capacity less than 24,500 Btu/h. Id.
Samsung specifically pointed out that many of their Low Static
Ducted Variable-Speed Mini-Split Heat Pumps (``Low Static VSMSHP'')
were previously covered by appendix M (Table 4 of Section 3.1.4.1), but
cannot be tested according to appendix M1, because these products have
a maximum operating ESP of 0.24 inches w.c. and cannot operate at the
0.5 inches w.c. set as the minimum ESP in appendix M1. (Samsung, No.22
at pp.2-3) They further asserted that their Low Static VSMSHPs \45\
were designed to be installed in tight locations, that they can be
installed with or without ducts, and that there are other manufacturers
that Samsung is aware of that currently manufacture and sell similar
products. (Samsung, No.22 at p.3)
---------------------------------------------------------------------------
\45\ Samsung provided information about their Low Static VSMSHP,
which is available online at: https://www.samsunghvac.com/light-commercial/slim-duct.
---------------------------------------------------------------------------
DOE has received no petitions for waiver of the CAC test procedure
from any manufacturers requesting relief from the ESP conditions set in
appendix M1. Additionally, in the November 2015 SNOPR, DOE did propose
to establish a ``short-ducted'' product class with lower ESP testing
requirements (80 FR 74020, 69355) but stakeholders ultimately rejected
this proposal, as reflected by the 2016 CAC Term Sheet recommending ESP
levels for various types of CAC systems. Notably, ``short-duct''
configurations were not included in that list, so short-duct systems
would be considered ``conventional'' single-split ducted systems. Also,
recommendation #2 of the 2016 CAC Term Sheet states that the minimum
required ESP for CAC/HP blower coil systems other than mobile home
systems, ceiling-mount and wall-mount systems, low and mid-static
multi-split systems, space-constrained systems, and small-duct, high-
velocity systems should be 0.50 inches w.c. for all capacities. (See
2016 CAC Term Sheet: Docket No. EERE-2014-BT-STD-0048, No. 76) During
the August 2016 SNOPR public meeting and in written comments, many
stakeholders expressed support for the new minimum external static
requirements that DOE proposed. JCI, Goodman, Unico, AHRI, NEEA,
Carrier/UTC, Lennox, Ingersoll Rand, and Nortek expressed support for
DOE's proposal to require conventional systems to be tested at a
minimum external static pressure of 0.5 inches w.c. consistent with
Recommendation #2 of the 2016 CAC Term Sheet. (JCI, No. 24 at p. 15;
Goodman, No. 39 at p. 13; Unico, No. 30 at p. 6; AHRI, No. 27 at p. 16;
NEEA, No. 35 at p. 3; Carrier/UTC, No. 36 at p. 9; Lennox, No. 25 at p.
10; Ingersoll Rand, No. 38 at p. 5; Nortek, No. 22 at p. 11)
Based on the evidence presented in the previous paragraph, DOE
believes that revising the definition of low-static blower coil
systems, as suggested by AHRI and Samsung, would conflict with the
intent of stakeholders' comments when establishing appendix M1, and
could potentially create an unfair competitive advantage for such
systems by allowing more lenient testing conditions (and thus
comparatively higher ratings) as compared to conventional centrally-
ducted systems tested at minimum ESPs exceeding 0.50 inches w.c.
Therefore, DOE is not revising the definition for low-static blower
coil systems in this final rule, nor is it including any new test
provisions to accommodate these system types. DOE notes that there is
no restriction in the definition for non-ducted indoor units that would
preclude these systems from being tested and certified as non-ducted
systems, comparable to 1-to-1 mini-splits. See section 1.2 of appendix
M1. DOE also notes that its regulations at 10 CFR 430.27 provide that
any interested person may seek a waiver from the test procedure
requirements if certain conditions are met. A waiver allows
manufacturers to use an alternate test procedure upon the grounds that
the basic model contains one or more design characteristics which
either prevent testing of the basic model according to the prescribed
test procedures or cause the prescribed test
[[Page 64576]]
procedures to evaluate the basic model in a manner so unrepresentative
of its true energy and/or water consumption characteristics as to
provide materially inaccurate comparative data. 10 CFR 430.27(a)(1).
c. Revisions to Both Appendices M and M1
AHRI Exhibit 2 claimed that there are two sections in both
appendices M and M1 that contain similar errors. 87 FR 16830, 16846-
16847. These errors are detailed below in Table III-6. DOE is
finalizing these revisions as proposed by AHRI and indicated in the
table.
[GRAPHIC] [TIFF OMITTED] TR25OC22.012
The following sections discuss changes to the language of both
appendices M and M1 that DOE believes will improve clarity regarding
how tests and calculations are to be conducted to determine capacity
levels and efficiency metrics.
i. Revising Part Load Factor Equation for Heat Pumps in Section 4.2.3.3
AHRI's comment claims that the part load factor (PLF) equation in
section 4.2.3.3 of both appendices M and M1 contain two errors. (``AHRI
Exhibit 2,'' EERE-2017-BT-STD-0062-0117 at p. 23) The first error is
that the equation is missing a closing square bracket, and the second
is that the heating mode low-capacity load factor,
``X\k=1\(Tj),'' is incorrectly referenced instead of the
high-capacity load factor, ``X\k=2\(Tj).'' Id. DOE notes
that this equation is actually correct in appendix M1. The high-
capacity load factor is appropriate in this equation because section
4.2.3.3 applies to heat pumps that only operate at high (k=2)
compressor capacity. Therefore, the high-capacity load factor should be
used in this case for the part load factor. In the March 2022 CAC TP
NOPR, DOE proposed to revise this formula in appendix M to include the
closing square bracket and to use the high-capacity load factor. 87 FR
16830, 16846. DOE did not receive any comments in response to its
proposal and is therefore finalizing as proposed in this rule.
ii. Revising the Ratio of Electrical Energy Used for Resistive
Space Heating Equation in Section 4.2.3.4
AHRI has identified an error in the equation for electrical energy
consumed by the heat pump for electric resistance auxiliary heating for
bin temperature, Tj divided by the total number of hours in
the heating season, ``RH(Tj)/N,'' used in section 4.2.3.4 of
both appendices M and M1. AHRI indicated that the equation used in
section 4.2.3.4 includes a multiplication operator where it should have
subtraction. 87 FR 16830, 16846-16847. The subtraction operator is
consistent with all other instances of RH(Tj)/N in both
appendices M and M1. DOE agrees that the equation for
RH(Tj)/N in section 4.2.3.4 of both appendices M and M1 is
incorrect, and therefore DOE is revising this equation to include the
subtraction operator rather than a multiplication operator.
E. Other Revisions Regarding Representations
Manufacturers, including importers, must use product-specific
certification templates to certify compliance to DOE. For CAC/HPs, the
certification template reflects the general certification requirements
specified at 10 CFR 429.12 and the product-specific requirements
specified at 10 CFR 429.16. As discussed in the previous paragraphs,
DOE is not making any amendments related to certification requirements
in this rulemaking and any such changes may be addressed in a future
rulemaking.
1. Required Represented Values for Models Certified Compliant With
Regional Standards
DOE's standards for CAC at 10 CFR 430.32(c) include both amended
national standards with which compliance is required for models
manufactured on or after January 1, 2023, and amended regional
standards with which compliance is required for units installed on or
after January 1, 2023. See 10 CFR 430.32(c)(5) and (6). In addition, as
discussed in section III.B.3, DOE's regulations at 10 CFR 429.16
describe certification requirements for central air conditioners
[[Page 64577]]
and central air conditioning heat pumps, and paragraph (a)(1) of the
section requires single-split CACs with single-stage or two-stage
compressors, at a minimum, to rate each outdoor model as part of a
coil-only combination representative of the least efficient combination
distributed in commerce with that particular outdoor unit.
On December 16, 2021, DOE issued final guidance regarding whether a
model of outdoor unit for a single-split-system AC with single-stage or
two-stage compressor whose coil-only rating under M1 does not meet
regional standards, but where certain blower-coil combinations that
include the outdoor model do meet regional standards, can be installed
in the SE or SW region (referred to in this final rule as the ``CAC
Regional Guidance'').\46\ DOE's guidance states that ``In order to be
installed in the SE or SW region, the outdoor unit must have at least
one coil-only combination that is compliant with the regional standard
applicable at the time of installation.''
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\46\ The CAC Regional Guidance is available online at https://www.energy.gov/sites/default/files/2021-12/cac-regional-guidance.pdf.
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As background, DOE finalized provisions related to this issue in
the June 2016 CAC TP Final Rule (81 FR 36992, 37001) with subsequent
minor revisions via the January 2017 CAC TP Final Rule (82 FR 1426); a
July 2016 final rule regarding enforcement (81 FR 45387, July 14, 2016)
(``July 2016 Enforcement Final Rule''); and the January 2017 CAC ECS
Direct Final Rule (82 FR 1786, January 6, 2017). These provisions were
based on consensus recommendations by two ASRAC Working Groups--a
Regional Standards Enforcement Working Group (``Enforcement WG'') that
concluded on October 24, 2014 (see final report: Docket No. EERE-2011-
BT-CE-0077, No. 70), and a Central Air Conditioner and Heat Pump Energy
Conservation Standards Working Group (``ECS WG'') that concluded on
January 19, 2016 (see 2016 CAC Term Sheet: Docket No. EERE-2014-BT-STD-
0048, No. 76).
The July 2016 Enforcement Final Rule adopted several provisions of
relevance here, with a focus on enforcement of the existing energy
conservation standards:
10 CFR 429.102(c)(4) contains provisions regarding what a
``product installed in violation'' includes, specifying, among other
things: (1) A complete central air conditioning system that is not
certified as a complete system that meets the applicable standard; (2)
combinations that were previously validly certified may be installed
after the manufacturer has discontinued the combination, provided the
combination meets the currently applicable standard; and (3) an outdoor
unit that is part of a certified combination rated less than the
standard applicable in the region in which it is installed. 81 FR
45387, 45393-45394.
10 CFR 429.158(a) specifies that if DOE determines a model
of outdoor unit fails to meet the applicable regional standard(s) when
tested in a combination certified by the same manufacturer, then the
outdoor unit basic model will be deemed noncompliant with the regional
standard(s). 81 FR 45387, 45397.
10 CFR 430.32(c)(3) and (4) provides that any outdoor unit
model that has a certified combination with a rating below 14 SEER
cannot be installed in either the southern or southwest region. 81 FR
45387, 45391.
The June 2016 CAC TP Final Rule adopted several certification
provisions of relevance here, with a focus on the amended energy
conservation standards recommended by the ECS WG. In particular, the
June 2016 CAC TP Final Rule noted that the ECS WG recommended energy
conservation standards for central air conditioners based on coil-only
ratings. 81 FR 36992, 37002 (June 8, 2016). The recommended standard
levels for split system air conditioners may very well have been higher
if they had been based on blower-coil ratings. For example, the
recommended standard levels for split system heat pumps, which are
based on blower-coil ratings, are approximately one point higher than
those for split system air conditioners.
In addition, the ECS WG recommended that DOE implement the
requirement that every single-split air conditioner combination
distributed in commerce must be rated, and that every single-stage and
two-stage condensing (outdoor) unit distributed in commerce (other than
a condensing unit for a 1-to-1 mini split) must have at least 1 coil-
only rating that is representative of the least efficient coil
distributed in commerce with a particular condensing unit. Every
condensing unit distributed in commerce must have at least 1 tested
combination, and for single-stage and two-stage condensing units (other
than condensing units for a 1-to-1 mini split) this must be a coil-only
combination. (Docket No. EERE-2014-BT-STD-0048, No. 76, Recommendation
#7) In the June 2016 CAC TP Final Rule, DOE adopted these
recommendations along with regional limitations for represented values
of individual combinations:
10 CFR 429.16(a)(1) contains provisions for required
represented values, stating that for single-split system AC with
single-stage or two-stage compressor, every individual combination
distributed in commerce must be rated as a coil-only combination. For
each model of outdoor unit, this must include at least one coil-only
value that is representative of the least efficient combination
distributed in commerce with that particular model of outdoor unit.
Additional blower-coil representations are allowed for any applicable
individual combinations, if distributed in commerce. 81 FR 36992,
37002.
10 CFR 429.16(b)(2)(i) specifies that for each basic model
of single-split system AC with single-stage or two-stage compressor,
the model of outdoor unit must be tested with a model of coil-only
indoor unit. 81 FR 36992, 37002.
10 CFR 429.16(a)(4)(i) [as modified in the January 2017
CAC TP Final Rule] states that a basic model may only be certified as
compliant with a regional standard if all individual combinations
within that basic model meet the regional standard for which it is
certified, and that a model of outdoor unit that is certified below a
regional standard can only be rated and certified as compliant with a
regional standard if the model of outdoor unit has a unique model
number and has been certified as a different basic model for
distribution in each region. 81 FR 36992, 37012 [as 10 CFR
429.16(a)(3)(i)]; 82 FR 1426.
DOE notes that the July 2016 Enforcement Final Rule stated that the
adopted provisions in 10 CFR 430.32(c)(3) and (4) were meant to be
complementary to the regional limitations adopted in the June 2016 CAC
TP Final Rule at 10 CFR 429.16(a)(3)(i) [now 10 CFR 429.16(a)(4)(i)].
81 FR 45387, 45391. In the January 2017 CAC ECS Direct Final Rule, DOE
adopted additional language in 10 CFR 430.32 relevant to the amended
standards:
10 CFR 430.32(c)(6)(ii) provides that any outdoor unit
model that has a certified combination with a rating below the
applicable standard level(s) for a region cannot be installed in that
region. The least-efficient combination of each basic model must comply
with this standard. 82 FR 1786, 1857.
Finally, DOE notes that the general enforcement provisions in
subpart C to part 429 also apply to CAC standards (both national and
regional), including:
10 CFR 429.102(a)(1), specifying that the failure of a
manufacturer to properly certify covered products in accordance with 10
CFR 429.12 and 429.14 through 429.62 is a prohibited act subject to
enforcement action.
[[Page 64578]]
Taken together, the regional standards, certification, and
enforcement provisions require that, in order to comply with a regional
standard, the least efficient combination of each basic model must
comply. 10 CFR 430.32(c)(6)(ii). Further, each basic model of single-
split system AC with single-stage or two-stage compressor must include
a represented value for a coil-only combination representative of the
least efficient combination distributed in commerce with the model of
outdoor unit, and each model of outdoor unit must be tested with a
model of coil-only indoor unit. (10 CFR 429.16(a)(1) and (b)(2)(i))
While manufacturers can create a regional-specific basic model under 10
CFR 429.16(a)(4)(i), such a basic model must still be certified
properly according to the other provisions in that section. As such, in
order to comply with a regional standard, a regional-specific basic
model of single-split system AC with single-stage or two-stage
compressor must include at least one coil-only combination that
complies with the regional standard. Failure to certify a regional-
specific basic model according to the provisions in 10 CFR 429.16(a)(1)
and (b)(2)(i) is a prohibited act under 10 CFR 429.102(a)(1).
Similarly, 10 CFR 429.102(c)(4)(i) states that combinations that
were previously validly certified may be installed after the
manufacturer has discontinued the combination, provided the combination
meets the currently applicable standard. The provision at 10 CFR
429.102(c)(4)(i) was designed to allow sell-through of inventory that
manufacturers had discontinued for reasons other than non-compliance
with a regional standard. 81 FR 45387, 45393. It was not intended, nor
in the light of all other provisions can it be read, as allowing
installation of models of outdoor unit that do not comply with the
applicable regional standard at the time of installation (i.e., have no
combinations of coil-only units that comply with the amended regional
standards, which, as stated previously, were developed based on coil-
only ratings). Based on this background, the CAC regional guidance
states in part:
In general, a basic model may be certified as compliant with a
regional standard (and, as of January 1, 2023, meets the applicable
amended regional standard) only if all individual combinations within
that basic model meet the regional standard for which it is certified.
All individual model combinations within a basic model must include,
for single-split-system AC with single-stage or two-stage compressor
(including space-constrained and small-duct, high velocity (SDHV)
systems), a coil-only combination representative of the least-efficient
combination in which the specific outdoor unit is distributed in
commerce. See 10 CFR 429.16(a)(1) and (a)(4)(i); 430.32(c)(6).
A manufacturer may sell an outdoor unit of identical design in the
SE and SW regions, if the manufacturer separates the basic model (i.e.,
outdoor unit model) into different basic models with unique model
numbers for distribution in each region, provided that the basic models
for the SE and SW regions: (1) do not include any individual
combinations that are not compliant with the regional standard
applicable at the time of installation; and (2) include at least one
coil-only combination that is representative of the least-efficient
combination in which the specific outdoor unit is distributed in
commerce. Id.
DOE notes that the install-through provisions in 10 CFR
429.102(c)(4)(i) allows existing stock of discontinued basic model
combinations to be installed in the SE or SW regions as long as they
were previously validly certified as compliant to the regional
standards applicable at the time of installation. DOE further notes
that the term ``previously validly certified'' means that all
combinations within the basic model must show compliance with the
regional standard applicable at the time of installation, including,
for single-split-system AC with single-stage or two-stage compressor
(including space-constrained and SDHV systems), a coil-only combination
representative of the least-efficient combination in which the specific
outdoor unit is distributed in commerce, in order for the install-
through provisions to apply.
In the March 2022 CAC TP NOPR, DOE proposed to add direction to the
regulatory text in 10 CFR 429.16(a)(1) and (a)(4)(i), 429.102(c)(4)(i)
and (iii), and 430.32(c)(6)(ii) to more explicitly cross-reference the
existing regulatory text to clarify the interplay of the existing
requirements and reinforce the guidance. 87 FR 16830, 16848.
In addition, DOE notes that the table in 10 CFR 429.16(a)(1) states
that the required coil-only value must be ``representative of the least
efficient combination distributed in commerce with that particular
model of outdoor unit'' (emphasis added). Sections 429.140 through
429.158 provide enforcement procedures specific to regional standards,
10 CFR 429.142 includes records retention of information regarding
sales of outdoor units, indoor units, and single-package units, and 10
CFR 429.144 specifies requirements for records requests. When
determining if a model of indoor unit is distributed in commerce with a
particular model of outdoor unit, DOE may review catalogs, product
literature, installation instructions, and advertisements, and may also
request sales records.
Finally, 10 CFR 429.158 discusses products determined noncompliant
with regional standards. Paragraphs (a) and (b) cross-reference 10 CFR
429.102(c), stating that the certifying manufacturer is liable for
distribution of noncompliant units in commerce. DOE notes that 10 CFR
429.102(c) refers to distributors, contractors, and dealers, while 10
CFR 429.102(a)(10) states that it is prohibited ``for any manufacturer
or private labeler to knowingly sell a product to a distributor,
contractor, or dealer with knowledge that the entity routinely violates
any regional standard applicable to the product.'' Therefore, DOE
proposed in the March 2022 CAC TP NOPR that 10 CFR 429.158(a) and (b)
cross-reference 10 CFR 429.102(a)(10) rather than 10 CFR
429.102(c).\47\ 87 FR 16830, 16848.
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\47\ In the March 2022 CAC TP NOPR, DOE had mistakenly modified
10 CFR 429.102(c) to 10 CFR 429.102(b) in the regulatory text.
Daikin has pointed this out (Daikin, No. 24 at p. 2), and the
corrections have been made in the regulatory text for the final
rule.
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In response, the Joint Advocates and Lennox declared that they
supported DOE's proposed regulatory text in 10 CFR part 429 that
clarified the requirements regarding required represented values for
models certified compliant with regional standards. (Joint Advocates,
No. 18 at p. 3, Lennox, No. 19 at p. 5) DOE is therefore finalizing its
proposals from the March 2022 CAC TP NOPR to amend Sec. Sec. 429.16,
429.102, 429.158, and 430.32 to clarify the interaction of the existing
requirements and reinforce the guidance.
Additionally, Rheem commented that DOE should provide additional
clarity on the efficiency cross references between appendices M and M1
for products installed on or after January 1, 2023. (Rheem, No. 21 at
p. 4) Because Rheem did not identify any specific issues regarding the
clarity of DOE's proposed provisions, DOE cannot further clarify them
at this time.
F. Test Procedure Costs and Impact
As discussed, DOE's existing test procedures for CAC/HPs appear at
appendices M and M1 (both titled ``Uniform Test Method for Measuring
the Energy Consumption of Central Air Conditioners and Heat Pumps'').
In this final rule, DOE is amending the existing test procedure for
CACs and HPs to
[[Page 64579]]
provide additional detail and instruction to ensure the
representativeness of the test procedure and to reduce potential
burden. DOE is making amendments in appendix M that do not impact
testing procedures and solely provide additional clarity. DOE is also
making limited amendments to appendix M1, which is the required test
procedure beginning January 1, 2023. For each amendment described in
this final rule, DOE considered the potential for changes to test
procedure costs.
Regarding the test procedure for variable speed coil-only central
air conditioners and heat pumps (described in III.C.2), DOE's
amendments provide new instructions for testing VSCO systems which are
not currently prescribed in the DOE test procedure, despite the fact
that these products are currently subject to energy conservation
standards. Because the current test provisions are insufficient for
testing VSCO, the relative cost of the amended provisions cannot be
compared. Regarding the amendments to introduce a low-stage default
coil-only fan power coefficient (described in III.C.1) and to revise
the equations for full-capacity operation of variable-speed heat pumps
at and above 45 [deg]F (described in III.D.5), DOE finds that these
amendments would only impact calculation methods and would have no
impact on test costs.
There are several other test procedure amendments which DOE
similarly does not believe will cause manufacturers to incur any
additional test procedure costs. Specifically, the amendments described
in section III.D.1 revise text regarding variation of fan speed with
ambient temperature; the amendments described in section III.D.4
explicitly indicate that the airflow measurement apparatus fan should
be adjusted to maintain constant airflow for certain models, and the
amendments described in section III.D.3 clarify that the instructions
on a label affixed to the unit take precedence over the instructions
shipped with the unit. DOE finds that these revisions each provide
additional instruction to improve consistency of testing but do not
increase either the number of tests or the duration of tests. The
amendment to the wet bulb temperature maximum for the 5 [deg]F ambient
temperature condition, discussed in section III.D.2, adjusts the
required test condition from 3 [deg]F to 4 [deg]F. DOE proposed this
change in part based on feedback from manufacturers that the proposed
change to 4 [deg]F wet bulb temperature maximum would be easier to
achieve than 3 [deg]F and would require less time spent trying to
achieve conditions. As such, DOE does not anticipate that this
provision would increase the burden of conducting testing under
appendix M1.
Finally, the amendments in 10 CFR part 429 neither modify the test
procedure nor increase the number of units that would be required to be
tested. Thus, DOE does not anticipate these additional procedures will
cause any increased test procedure costs.
DOE has, therefore, determined that the test procedures as amended
by this final rule would improve the representativeness, accuracy, and
reproducibility of the test results, and would not be unduly burdensome
for manufacturers to conduct or result in increased testing cost as
compared to the current test procedure.
G. Compliance Date and Waivers
The effective date for the adopted test procedure amendment will be
30 days after publication of this final rule in the Federal Register.
EPCA prescribes that, beginning 180 days after publication of the final
rule in the Federal Register, all representations of energy efficiency
and energy use, including those made on marketing materials and product
labels, must be made in accordance with an amended test procedure. (42
U.S.C. 6293(c)(2)) EPCA provides an allowance for individual
manufacturers to petition DOE for an extension of the 180-day period if
the manufacturer may experience undue hardship in meeting the deadline.
(42 U.S.C. 6293(c)(3)) To receive such an extension, petitions must be
filed with DOE no later than 60 days before the end of the 180-day
period and must detail how the manufacturer will experience undue
hardship. Id. To the extent the modified test procedure adopted in this
final rule is required only for the evaluation and issuance of updated
efficiency standards, compliance with the amended test procedure does
not require use of such modified test procedure provisions until the
compliance date of updated standards.
Upon the compliance date of test procedure provisions in this final
rule any waivers that had been previously issued and are in effect that
pertain to issues addressed by such provisions are terminated. 10 CFR
430.27(h)(3). Recipients of any such waivers are required to test the
products subject to the waiver according to the amended test procedure
as of the compliance date of the amended test procedure. The amendments
adopted in this document pertain to issues addressed by waivers granted
to GD Midea Heating and Ventilating Equipment Co. (83 FR 56065, Case
No. 2017-013) and TCL AC (84 FR 11941, Case No. 2018-009); and interim
waivers granted to National Comfort Products (83 FR 24754, Case No.
2017-008), Aerosys (83 FR 24762, Case No. 2017-008), LG Electronics (85
FR 40272, Case No. 2019-008), and Goodman (86 FR 40534, Case No. 2021-
001). To the extent such waivers and interim waivers permit the
petitioner to test according to an alternate test procedure to appendix
M, such waivers and interim waivers will terminate on the date testing
is required according to appendix M1 (i.e., January 1, 2023),
independent of this rulemaking. To the extent such waivers and interim
waivers permit the petitioner to test according to an alternate test
procedure to appendix M1 at such time as testing is required according
to appendix M1, such waivers and interim waivers will terminate on
January 1, 2023. DOE notes that the waiver issued to Johnson Controls
(83 FR 12735, Case No. CAC-051; 84 FR 52489, Case No. CAC-050) will
terminate on January 1, 2023, the date beginning which testing
according to appendix M1 is required, independent of this final rule.
H. Requests for Standards Relief
DOE understands that changes to testing requirements may create
additional burdens for ensuring compliance with the amended energy
conservations that take effect on January 1, 2023, and those effects
may not be realized equally across different types and sizes of
manufacturers. In response to the March 2022 CAC TP NOPR, DOE received
a comment from at interested party (LBA, No. 3) requesting relief from
standards, which is discussed.
As previously introduced, LBA also commented on the March 2022 CAC
TP NOPR requesting relief from energy conservations standards.
Specifically, LBA requested DOE to delay the installation deadline for
products that will be compliant with the new Regional Standards, citing
the issues in unprecedented delays of products due to the current state
of the global supply chain. (LBA, No.3 at p.1) LBA requested DOE to
delay the installation of new CAC/HPs compliant with appendix M1 in the
Southeast and Southwest Regions to July 1, 2023. Id. LBA stated that
for constructions of new homes, the air handler unit, furnace and fans
(i.e., the indoor components) are installed during the ``rough-in''
phase, while the outdoor condensing unit is installed several months
later during ``closing''. Id. Hence, LBA believes that a delay in the
deadlines of enforcement of Regional Standards would allow pairing of
equipment compliant with the SEER1 rating (appendix M) with that
complaint with SEER2 (appendix M1). Id.
[[Page 64580]]
In response to the LBA request for relief, while DOE recognizes
that manufacturers across various industries are facing unique and
unforeseeable circumstances in light of the global effects of the
pandemic, and that the scope of those impacts will vary by company, by
product, and possibly even by model, DOE is not at this time extending
this type of relief from compliance with the 2023 energy conservation
standards. In consideration of these requests, DOE takes into account
the full range of these circumstances and their impacts, including any
factors that may be unique to particular products or equipment,
including the lead time in advance of the relevant compliance date. In
this regard, DOE notes that the regional standards applicable to
central air conditioners installed on or after January 1, 2023, were
adopted in a direct final rule more than five years ago, in January
2017. Moreover, the rule was a product of negotiated rulemaking that
included various manufacturers and trade representatives.
Although no manufacturers specifically requested relief from
standards, DOE notes that standards compliance is a factor in specific
issues raised by certain commenters, specifically the case of NCP's
space-constrained products. In its waiver request, NCP requested that
if DOE does not incorporate provisions from the previously granted
interim test procedure waiver into the amended Federal test procedure
in appendix M1, then DOE must allow for NCP to continue testing and
certifying its space-constrained CACs in a manner consistent with the
granted test procedure waivers until 2025, noting the time needed to
modify its condensing units and certify them as compliant with the
amended standards, and asserted that because their space-constrained
condensing units represent less than 0.1 percent of the overall CAC
market, the requested delay in test procedure effective date would not
have a significant impact on overall energy efficiency.\48\ (NCP, No 16
at pp. 9-10) While the specific request in NCP's comments pertain to
the testing and certification requirements, an extension of these
provisions would effectively provide NCP with a less burdensome near-
term pathway to compliance with the 2023 standards relative to other
manufacturers who are subject to the existing provisions. For reasons
stated previously in this rule, DOE takes the view that, based on the
considerations given in prior energy conservation standards and test
procedure rulemakings, NCP and other space-constrained product
manufacturers have had sufficient time to adjust their product designs
to ensure compliance with the energy conservation standards.
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\48\ DOE is interpreting NCP's statement to mean ``overall
energy use'', which would be the relevant metric impacted by changes
in composition of the CAC market.
---------------------------------------------------------------------------
However, in acknowledgement of the potential inequities in
compliance burdens as described by NCP and LBA, DOE notes that
additional compliance flexibilities for small business manufacturers
may be available through other means. For example, EPCA provides that a
manufacturer whose annual gross revenue from all of its operations does
not exceed $8 million may apply for an exemption from all or part of an
energy conservation standard for a period not longer than 24 months
after the effective date of the final rule establishing the standard.
Additionally, section 504 of the Department of Energy Organization Act
(42 U.S.C. 7194, as codified), provides authority for the Secretary to
adjust a rule issued under EPCA in order to prevent ``special hardship,
inequity, or unfair distribution of burdens'' that may be imposed on
that manufacturer as a result of such rule. Manufacturers should refer
to 10 CFR part 430, subpart E, and 10 CFR part 1003 for additional
details.
With respect to representations, DOE notes that under 42 U.S.C.
6293(c)(2), effective 180 days after an amended test procedure is
prescribed or established, no manufacturer, distributor, retailer, or
private labeler of a covered product may make any representation with
respect to energy use or efficiency unless such product has been tested
in accordance with such amended test procedures and such representation
fairly discloses the results of such testing. Additionally, under 42
U.S.C. 6293(c)(3), on the petition of any manufacturer, distributor,
retailer, or private labeler, filed not later than the 60th day before
the expiration of the period involved, the aforementioned 180-day
period may be extended by the Secretary with respect to the petitioner
(but in no event for more than an additional 180 days) if the Secretary
determines that the requirements of paragraph (c)(2) would impose undue
hardship on such petitioner.
IV. Procedural Issues and Regulatory Review
A. Review Under Executive Orders 12866 and 13563
Executive Order (``E.O.'') 12866, ``Regulatory Planning and
Review,'' as supplemented and reaffirmed by E.O. 13563, ``Improving
Regulation and Regulatory Review,'' 76 FR 3821 (Jan. 21, 2011),
requires agencies, to the extent permitted by law, to (1) propose or
adopt a regulation only upon a reasoned determination that its benefits
justify its costs (recognizing that some benefits and costs are
difficult to quantify); (2) tailor regulations to impose the least
burden on society, consistent with obtaining regulatory objectives,
taking into account, among other things, and to the extent practicable,
the costs of cumulative regulations; (3) select, in choosing among
alternative regulatory approaches, those approaches that maximize net
benefits (including potential economic, environmental, public health
and safety, and other advantages; distributive impacts; and equity);
(4) to the extent feasible, specify performance objectives, rather than
specifying the behavior or manner of compliance that regulated entities
must adopt; and (5) identify and assess available alternatives to
direct regulation, including providing economic incentives to encourage
the desired behavior, such as user fees or marketable permits, or
providing information upon which choices can be made by the public. DOE
emphasizes as well that E.O. 13563 requires agencies to use the best
available techniques to quantify anticipated present and future
benefits and costs as accurately as possible. In its guidance, the
Office of Information and Regulatory Affairs (``OIRA'') in the Office
of Management and Budget (``OMB'') has emphasized that such techniques
may include identifying changing future compliance costs that might
result from technological innovation or anticipated behavioral changes.
For the reasons stated in the preamble, this final regulatory action is
consistent with these principles.
Section 6(a) of E.O. 12866 also requires agencies to submit
``significant regulatory actions'' to OIRA for review. OIRA has
determined that this final regulatory action does not constitute a
``significant regulatory action'' under section 3(f) of E.O. 12866.
Accordingly, this action was not submitted to OIRA for review under
E.O. 12866.
B. Review Under the Regulatory Flexibility Act
The Regulatory Flexibility Act (5 U.S.C. 601 et seq.) requires
preparation of a final regulatory flexibility analysis (FRFA) for any
final rule where the agency was first required by law to publish a
proposed rule for public comment, unless the agency certifies
[[Page 64581]]
that the rule, if promulgated, will not have a significant economic
impact on a substantial number of small entities. As required by
Executive Order 13272, ``Proper Consideration of Small Entities in
Agency Rulemaking,'' 67 FR 53461 (August 16, 2002), DOE published
procedures and policies on February 19, 2003, to ensure that the
potential impacts of its rules on small entities are properly
considered during the DOE rulemaking process. 68 FR 7990. DOE has made
its procedures and policies available on the Office of the General
Counsel's website: www.energy.gov/gc/office-general-counsel.
DOE is establishing a limited number of amendments to the test
procedure for central air conditioners and heat pumps (``CAC/HPs'') to
address specific issues that have been raised in test procedure waivers
regarding appendix M1 to subpart B of 10 CFR part 430. In this final
rule, DOE is adopting the following updates to the test procedure for
CACs/HPs:
1. Update default fan power coefficients and default fan heat
coefficients for coil-only CACs and HPs that can utilize part-load air
volume rates.
2. Define ``variable-speed communicating coil-only central air
conditioner or heat pump'' and prescribe an appropriate test procedure.
3. Add the control system capability to adjust air volume rate as a
function of outdoor air temperature for blower-coil systems with
multiple-speed or variable-speed indoor fans.
4. Amend the wet bulb test condition for the 5 [deg]F dry bulb,
outdoor ambient test to have a 4 [deg]F maximum wet bulb temperature.
5. Add direction to prioritize the instructions presented in the
label attached to the unit over the instructions included in the
installation instructions shipped with the unit.
6. Add specific instruction to adjust the exhaust fan speed to
achieve a constant cooling full-load air volume rate through the
airflow measurement apparatus.
7. Revise the equations representing full-capacity performance of
variable-speed heat pumps for the temperature range above 45 [deg]F to
be more consistent with field operation.
8. Provide additional direction regarding the regional standard
requirements in 10 CFR part 429.
For manufacturers of CACs/HPs, the Small Business Administration
(``SBA'') has set a size threshold, which defines those entities
classified as ``small businesses'' for the purposes of the statute. DOE
used the SBA's small business size standards to determine whether any
small entities would be subject to the requirements of the rule. See 13
CFR part 121. The equipment covered by this rule is classified under
North American Industry Classification System (``NAICS'') code
333415,\49\ ``Air-Conditioning and Warm Air Heating Equipment and
Commercial and Industrial Refrigeration Equipment Manufacturing.'' In
13 CFR 121.201, the SBA sets a threshold of 1,250 employees or fewer
for an entity to be considered as a small business for this category.
DOE identified manufacturers using DOE's Compliance Certification
Database (``CCD''),\50\ the AHRI database,\51\ the California Energy
Commission's Modernized Appliance Efficiency Database System
(``MAEDbS''),\52\ the ENERGY STAR Product Finder database,\53\ and
prior CAC/HP rulemakings. DOE used the publicly available information
and subscription-based market research tools (e.g., reports from Dun &
Bradstreet) \54\ to identify 33 original equipment manufacturers
(``OEMs'') of the covered equipment. Of the 33 OEMs, DOE identified
eight domestic manufacturers of CACs/HPs that meet the SBA definition
of a ``small business.''
---------------------------------------------------------------------------
\49\ The size standards are listed by NAICS code and industry
description and are available at: www.sba.gov/document/support--table-size-standards (last accessed on June 20, 2022).
\50\ DOE's Compliance Certification Database is available at:
www.regulations.doe.gov/ccms (last accessed June 20, 2022).
\51\ The AHRI Database is available at: www.ahridirectory.org/
(last accessed June 20, 2022).
\52\ California Energy Commission's MAEDbS is available at
cacertappliances.energy.ca.gov/Pages/ApplianceSearch.aspx (last
accessed June 20, 2022).
\53\ The ENERGY STAR Product Finder database is available at
energystar.gov/productfinder/ (last accessed June 20, 2022).
\54\ app.dnbhoovers.com.
---------------------------------------------------------------------------
As discussed in more detail in section III.F of this document, DOE
has determined that the amendments to the test procedure would not
require retesting or re-rating. For variable-speed coil-only units, DOE
notes that the test procedure adopted in this final rule provides new
instructions for testing VSCO systems that are not currently prescribed
in the DOE test procedure, despite the fact that these products are
currently subject to energy conservation standards. Because the current
test provisions are insufficient for testing VSCO, the relative cost of
the amended provisions cannot be compared. While DOE believes the
variable-speed coil-only units will be isolated to a very small
fraction of models distributed in commerce (i.e., less than 1 percent
based on manufacturer representations in DOE's current Compliance
Management Database), a manufacturer will need to ensure their
representations are made in accordance with these amendments. DOE notes
that none of the variable-speed coil-only basic models certified
currently with DOE are manufactured by small manufacturers.
Additionally, the test procedure amendments would not result in any
change in burden associated with the DOE test procedure for CACs/HP.
Therefore, DOE concludes that the test procedure amendments in this
final rule would not have a ``significant economic impact on a
substantial number of small entities,'' and that the preparation of a
FRFA is not warranted. DOE will transmit the certification and
supporting statement of factual basis to the Chief Counsel for Advocacy
of the Small Business Administration for review under 5 U.S.C. 605(b).
C. Review Under the Paperwork Reduction Act of 1995
Manufacturers of central air conditioners and heat pumps must
certify to DOE that their products comply with any applicable energy
conservation standards. To certify compliance, manufacturers must first
obtain test data for their products according to the DOE test
procedures, including any amendments adopted for those test procedures.
DOE has established regulations for the certification and recordkeeping
requirements for all covered consumer products and commercial
equipment, including central air conditioners and heat pumps. (See
generally 10 CFR part 429) The collection-of-information requirement
for the certification and recordkeeping is subject to review and
approval by OMB under the Paperwork Reduction Act (PRA). This
requirement has been approved by OMB under OMB control number 1910-
1400. Public reporting burden for the certification is estimated to
average 35 hours per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information.
DOE is not amending the certification or reporting requirements for
central air conditioners and heat pumps in this final rule. Instead,
DOE may consider proposals to amend the certification requirements and
reporting central air conditioners and heat pumps under a separate
rulemaking regarding appliance and equipment certification. DOE will
address changes to OMB Control Number 1910-1400 at that time, as
necessary.
[[Page 64582]]
Notwithstanding any other provision of the law, no person is
required to respond to, nor shall any person be subject to a penalty
for failure to comply with, a collection of information subject to the
requirements of the PRA, unless that collection of information displays
a currently valid OMB Control Number.
D. Review Under the National Environmental Policy Act of 1969
In this final rule, DOE establishes test procedure amendments that
it expects will be used to develop and implement future energy
conservation standards for central air conditioners and heat pumps. DOE
has determined that this rule falls into a class of actions that are
categorically excluded from review under the National Environmental
Policy Act of 1969 (42 U.S.C. 4321 et seq.) and DOE's implementing
regulations at 10 CFR part 1021. Specifically, DOE has determined that
adopting test procedures for measuring energy efficiency of consumer
products and industrial equipment is consistent with activities
identified in 10 CFR part 1021, appendix A to subpart D, A5 and A6.
Accordingly, neither an environmental assessment nor an environmental
impact statement is required.
E. Review Under Executive Order 13132
Executive Order 13132, ``Federalism,'' 64 FR 43255 (August 4,
1999), imposes certain requirements on agencies formulating and
implementing policies or regulations that preempt State law or that
have federalism implications. The Executive order requires agencies to
examine the constitutional and statutory authority supporting any
action that would limit the policymaking discretion of the States and
to carefully assess the necessity for such actions. The Executive order
also requires agencies to have an accountable process to ensure
meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.
On March 14, 2000, DOE published a statement of policy describing the
intergovernmental consultation process it will follow in the
development of such regulations. 65 FR 13735. DOE examined this final
rule and determined that it will not have a substantial direct effect
on the States, on the relationship between the National Government and
the States, or on the distribution of power and responsibilities among
the various levels of government. EPCA governs and prescribes Federal
preemption of State regulations as to energy conservation for the
products that are the subject of this final rule. States can petition
DOE for exemption from such preemption to the extent, and based on
criteria, set forth in EPCA. (42 U.S.C. 6297(d)) No further action is
required by Executive Order 13132.
F. Review Under Executive Order 12988
Regarding the review of existing regulations and the promulgation
of new regulations, section 3(a) of Executive Order 12988, ``Civil
Justice Reform,'' 61 FR 4729 (Feb. 7, 1996), imposes on Federal
agencies the general duty to adhere to the following requirements: (1)
eliminate drafting errors and ambiguity; (2) write regulations to
minimize litigation; (3) provide a clear legal standard for affected
conduct rather than a general standard; and (4) promote simplification
and burden reduction. Section 3(b) of Executive Order 12988
specifically requires that Executive agencies make every reasonable
effort to ensure that the regulation (1) clearly specifies the
preemptive effect, if any; (2) clearly specifies any effect on existing
Federal law or regulation; (3) provides a clear legal standard for
affected conduct while promoting simplification and burden reduction;
(4) specifies the retroactive effect, if any; (5) adequately defines
key terms; and (6) addresses other important issues affecting clarity
and general draftsmanship under any guidelines issued by the Attorney
General. Section 3(c) of Executive Order 12988 requires Executive
agencies to review regulations in light of applicable standards in
sections 3(a) and 3(b) to determine whether they are met or it is
unreasonable to meet one or more of them. DOE has completed the
required review and determined that, to the extent permitted by law,
this final rule meets the relevant standards of Executive Order 12988.
G. Review Under the Unfunded Mandates Reform Act of 1995
Title II of the Unfunded Mandates Reform Act of 1995 (``UMRA'')
requires each Federal agency to assess the effects of Federal
regulatory actions on State, local, and Tribal governments and the
private sector. Public Law 104-4, sec. 201 (codified at 2 U.S.C. 1531).
For a regulatory action resulting in a rule that may cause the
expenditure by State, local, and Tribal governments, in the aggregate,
or by the private sector of $100 million or more in any one year
(adjusted annually for inflation), section 202 of UMRA requires a
Federal agency to publish a written statement that estimates the
resulting costs, benefits, and other effects on the national economy.
(2 U.S.C. 1532(a), (b)) The UMRA also requires a Federal agency to
develop an effective process to permit timely input by elected officers
of State, local, and Tribal governments on a proposed ``significant
intergovernmental mandate,'' and requires an agency plan for giving
notice and opportunity for timely input to potentially affected small
governments before establishing any requirements that might
significantly or uniquely affect small governments. On March 18, 1997,
DOE published a statement of policy on its process for
intergovernmental consultation under UMRA. 62 FR 12820; also available
at www.energy.gov/gc/office-general-counsel. DOE examined this final
rule according to UMRA and its statement of policy and determined that
the rule contains neither an intergovernmental mandate, nor a mandate
that may result in the expenditure of $100 million or more in any year,
so these requirements do not apply.
H. Review Under the Treasury and General Government Appropriations Act,
1999
Section 654 of the Treasury and General Government Appropriations
Act, 1999 (Pub. L. 105-277) requires Federal agencies to issue a Family
Policymaking Assessment for any rule that may affect family well-being.
This final rule will not have any impact on the autonomy or integrity
of the family as an institution. Accordingly, DOE has concluded that it
is not necessary to prepare a Family Policymaking Assessment.
I. Review Under Executive Order 12630
DOE has determined, under Executive Order 12630, ``Governmental
Actions and Interference with Constitutionally Protected Property
Rights,'' 53 FR 8859 (March 18, 1988), that this regulation will not
result in any takings that might require compensation under the Fifth
Amendment to the U.S. Constitution.
J. Review Under Treasury and General Government Appropriations Act,
2001
Section 515 of the Treasury and General Government Appropriations
Act, 2001 (44 U.S.C. 3516 note) provides for agencies to review most
disseminations of information to the public under guidelines
established by each agency pursuant to general guidelines issued by
OMB. OMB's guidelines were published at 67 FR 8452 (Feb. 22, 2002), and
DOE's guidelines were published at 67 FR 62446 (Oct. 7, 2002). Pursuant
to OMB Memorandum M-19-15, Improving Implementation of the Information
Quality Act (April 24, 2019), DOE published updated guidelines which
are
[[Page 64583]]
available at www.energy.gov/sites/prod/files/2019/12/f70/DOE%20Final%20Updated%20IQA%20Guidelines%20Dec%202019.pdf. DOE has
reviewed this final rule under the OMB and DOE guidelines and has
concluded that it is consistent with applicable policies in those
guidelines.
K. Review Under Executive Order 13211
Executive Order 13211, ``Actions Concerning Regulations That
Significantly Affect Energy Supply, Distribution, or Use,'' 66 FR 28355
(May 22, 2001), requires Federal agencies to prepare and submit to OMB,
a Statement of Energy Effects for any significant energy action. A
``significant energy action'' is defined as any action by an agency
that promulgated or is expected to lead to promulgation of a final
rule, and that (1) is a significant regulatory action under Executive
Order 12866, or any successor order; and (2) is likely to have a
significant adverse effect on the supply, distribution, or use of
energy; or (3) is designated by the Administrator of OIRA as a
significant energy action. For any significant energy action, the
agency must give a detailed statement of any adverse effects on energy
supply, distribution, or use if the regulation is implemented, and of
reasonable alternatives to the action and their expected benefits on
energy supply, distribution, and use.
This regulatory action is not a significant regulatory action under
Executive Order 12866. Moreover, it would not have a significant
adverse effect on the supply, distribution, or use of energy, nor has
it been designated as a significant energy action by the Administrator
of OIRA. Therefore, it is not a significant energy action, and,
accordingly, DOE has not prepared a Statement of Energy Effects.
L. Review Under Section 32 of the Federal Energy Administration Act of
1974
Under section 301 of the Department of Energy Organization Act
(Pub. L. 95-91; 42 U.S.C. 7101), DOE must comply with section 32 of the
Federal Energy Administration Act of 1974, as amended by the Federal
Energy Administration Authorization Act of 1977. (15 U.S.C. 788;
``FEAA'') Section 32 essentially provides in relevant part that, where
a proposed rule authorizes or requires use of commercial standards, the
notice of proposed rulemaking must inform the public of the use and
background of such standards. In addition, section 32(c) requires DOE
to consult with the Attorney General and the Chairman of the Federal
Trade Commission (``FTC'') concerning the impact of the commercial or
industry standards on competition.
The modifications to the test procedure for central air
conditioners and heat pumps adopted in this final rule do not
incorporate any new commercial standards or test procedures that are
not already incorporated by reference \55\ at 10 CFR 430.3 and
therefore DOE has not re-assessed such standards as part of this final
rule.
---------------------------------------------------------------------------
\55\ The June 2016 CAC TP Final Rule incorporated by reference
into appendix M several commercial standards and test procedures. 81
FR 36992, 37056-37057. In the January 2017 CAC TP Final Rule, DOE
incorporated by reference in appendix M1 the same set of standards
and test procedures. 82 FR 1426, 1467.
---------------------------------------------------------------------------
M. Description of Materials Incorporated by Reference.
The following standard was previously approved for incorporation by
reference in appendix M1 where it appears, and no change is being made:
ANSI/ASHRAE Standard 37-2009, Methods of Testing for Rating
Electrically Driven Unitary Air-Conditioning and Heat Pump Equipment,
ANSI approved June 25, 2009;
N. Congressional Notification
As required by 5 U.S.C. 801, DOE will report to Congress on the
promulgation of this rule before its effective date. The report will
state that it has been determined that the rule is not a ``major rule''
as defined by 5 U.S.C. 804(2).
V. Approval of the Office of the Secretary
The Secretary of Energy has approved publication of this final
rule.
List of Subjects
10 CFR Part 429
Administrative practice and procedure, Confidential business
information, Energy conservation, Household appliances, Imports,
Intergovernmental relations, Reporting and recordkeeping requirements,
Small businesses.
10 CFR Part 430
Administrative practice and procedure, Confidential business
information, Energy conservation, Household appliances, Imports,
Incorporation by reference, Intergovernmental relations, Small
businesses.
Signing Authority
This document of the Department of Energy was signed on October 5,
2022, by Francisco Alejandro Moreno, Acting Assistant Secretary for
Energy Efficiency and Renewable Energy, pursuant to delegated authority
from the Secretary of Energy. That document with the original signature
and date is maintained by DOE. For administrative purposes only, and in
compliance with requirements of the Office of the Federal Register, the
undersigned DOE Federal Register Liaison Officer has been authorized to
sign and submit the document in electronic format for publication, as
an official document of the Department of Energy. This administrative
process in no way alters the legal effect of this document upon
publication in the Federal Register.
Signed in Washington, DC, on October 7, 2022.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
For the reasons stated in the preamble, DOE amends parts 429 and
430 of chapter II of title 10, Code of Federal Regulations as set forth
below:
PART 429--CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER
PRODUCTS AND COMMERCIAL AND INDUSTRIAL EQUIPMENT
0
1. The authority citation for part 429 continues to read as follows:
Authority: 42 U.S.C. 6291-6317; 28 U.S.C. 2461 note.
0
2. Section 429.16 is amended by:
0
a. Revising table 1 to paragraph (a)(1);
0
b. Revising paragraph (a)(4)(i); and
0
c. Revising the table in paragraph (b)(2)(i).
The revisions read as follows:
Sec. 429.16 Central air conditioners and central air conditioning
heat pumps.
(a) * * *
(1) * * *
[[Page 64584]]
Table 1 to Paragraph (a)(1)
------------------------------------------------------------------------
Equipment Required represented
Category subcategory values
------------------------------------------------------------------------
Single-Package Unit......... Single-Package Air Every individual
Conditioner (AC) model distributed
(including space- in commerce.
constrained).
Single-Package Heat
Pump (HP)
(including space-
constrained).
Outdoor Unit and Indoor Unit Single-Split-System Every individual
(Distributed in Commerce by AC with Single- combination
Outdoor Unit Manufacturer Stage or Two-Stage distributed in
(OUM)). Compressor commerce. Each
(including Space- model of outdoor
Constrained and unit must include a
Small-Duct, High represented value
Velocity Systems for at least one
(SDHV)). coil-only
individual
combination that is
distributed in
commerce and which
is representative
of the least
efficient
combination
distributed in
commerce with that
particular model of
outdoor unit. For
that particular
model of outdoor
unit, additional
represented values
for coil-only and
blower-coil
individual
combinations are
allowed, if
distributed in
commerce.
Single-Split System Every individual
AC with Other Than combination
Single-Stage or Two- distributed in
Stage Compressor commerce, including
(including Space- all coil-only and
Constrained and blower-coil
SDHV). combinations.
Single-Split-System Every individual
HP (including Space- combination
Constrained and distributed in
SDHV). commerce.
Multi-Split, Multi- For each model of
Circuit, or Multi- outdoor unit, at a
Head Mini-Split minimum, a non-
Split System--non- ducted ``tested
SDHV (including combination.'' For
Space-Constrained). any model of
outdoor unit also
sold with models of
ducted indoor
units, a ducted
``tested
combination.'' When
determining
represented values
on or after January
1, 2023, the ducted
``tested
combination'' must
comprise the
highest static
variety of ducted
indoor unit
distributed in
commerce (i.e.,
conventional, mid-
static, or low-
static). Additional
representations are
allowed, as
described in
paragraphs
(c)(3)(i) and (ii)
of this section,
respectively.
Multi-Split, Multi- For each model of
Circuit, or Multi- outdoor unit, an
Head Mini-Split SDHV ``tested
Split System--SDHV. combination.''
Additional
representations are
allowed, as
described in
paragraph
(c)(3)(iii) of this
section.
Indoor Unit Only Distributed Single-Split-System Every individual
in Commerce by Independent Air Conditioner combination
Coil Manufacturer (ICM). (including Space- distributed in
Constrained and commerce.
SDHV).
Single-Split-System
Heat Pump
(including Space-
Constrained and
SDHV).
Multi-Split, Multi- For a model of
Circuit, or Multi- indoor unit within
Head Mini-Split each basic model,
Split System--SDHV. an SDHV ``tested
combination.''
Additional
representations are
allowed, as
described in
paragraph
(c)(3)(iii) of this
section.
------------------------------------------------------------------------
Outdoor Unit with no Match Every model of
outdoor unit
distributed in
commerce (tested
with a model of
coil-only indoor
unit as specified
in paragraph
(b)(2)(i) of this
section).
------------------------------------------------------------------------
* * * * *
(4) * * *
(i) Regional. A basic model (model of outdoor unit) may only be
certified as compliant with a regional standard if all individual
combinations within that basic model meet the regional standard for
which it is certified, including the coil-only combination as specified
in paragraph (a)(1) of this section, as applicable. A model of outdoor
unit that is certified below a regional standard can only be rated and
certified as compliant with a regional standard if the model of outdoor
unit has a unique model number and has been certified as a different
basic model for distribution in each region, where the basic model(s)
certified as compliant with a regional standard meet the requirements
of the first sentence. An ICM cannot certify an individual combination
with a rating that is compliant with a regional standard if the
individual combination includes a model of outdoor unit that the OUM
has certified with a rating that is not compliant with a regional
standard. Conversely, an ICM cannot certify an individual combination
with a rating that is not compliant with a regional standard if the
individual combination includes a model of outdoor unit that an OUM has
certified with a rating that is compliant with a regional standard.
* * * * *
(b) * * *
(2) * * *
(i) * * *
[[Page 64585]]
Table 2 to Paragraph (b)(2)(i)
----------------------------------------------------------------------------------------------------------------
Category Equipment subcategory Must test: With:
----------------------------------------------------------------------------------------------------------------
Single-Package Unit................ Single-Package AC The individual model N/A.
(including Space- with the lowest
Constrained). seasonal energy
Single-Package HP efficiency ratio
(including Space- (SEER) (when testing
Constrained). in accordance with
appendix M to subpart
B of 10 CFR part 430)
or SEER2 (when
testing in accordance
with appendix M1 to
subpart B of 10 CFR
part 430).
Outdoor Unit and Indoor Unit Single-Split-System AC The model of outdoor A model of coil-only indoor
(Distributed in Commerce by OUM). with Single-Stage or unit. unit.
Two-Stage Compressor
(including Space-
Constrained and Small-
Duct, High Velocity
Systems (SDHV)).
Single-Split-System HP The model of outdoor A model of indoor unit.
with Single-Stage or unit.
Two-Stage Compressor
(including Space-
Constrained and SDHV).
Single-Split System AC The model of outdoor A model of non-
or HP with Other Than unit. communicating coil-only
Single-Stage or Two- indoor unit.
Stage Compressor
having a non-
communicating coil-
only individual
combination
(including Space-
Constrained and SDHV).
Single-Split System AC The model of outdoor A model of indoor unit.
or HP with Other Than unit.
Single-Stage or Two-
Stage Compressor
without a non-
communicating coil-
only individual
combination
(including Space-
Constrained and SDHV).
Multi-Split, Multi- The model of outdoor At a minimum, a ``tested
Circuit, or Multi- unit. combination'' composed
Head Mini-Split Split entirely of non-ducted
System--non-SDHV indoor units. For any
(including Space- models of outdoor units
Constrained). also sold with models of
ducted indoor units, test
a second ``tested
combination'' composed
entirely of ducted indoor
units (in addition to the
non-ducted combination).
If testing under appendix
M1 to subpart B of 10 CFR
part 430, the ducted
``tested combination''
must comprise the highest
static variety of ducted
indoor unit distributed in
commerce (i.e.,
conventional, mid-static,
or low-static).
Multi-Split, Multi- The model of outdoor A ``tested combination''
Circuit, or Multi- unit. composed entirely of SDHV
Head Mini-Split Split indoor units.
System--SDHV.
Indoor Unit Only (Distributed in Single-Split-System A model of indoor unit The least efficient model
Commerce by ICM). Air Conditioner of outdoor unit with which
(including Space- it will be paired where
Constrained and SDHV). the least efficient model
of outdoor unit is the
model of outdoor unit in
the lowest SEER
combination (when testing
under appendix M to
subpart B of 10 CFR part
430) or SEER2 combination
(when testing under
appendix M1 to subpart B
of 10 CFR part 430) as
certified by the OUM. If
there are multiple models
of outdoor unit with the
same lowest SEER (when
testing under appendix M
to subpart B of 10 CFR
part 430) or SEER2 (when
testing under appendix M1
to subpart B of 10 CFR
part 430) represented
value, the ICM may select
one for testing purposes.
Single-Split-System Nothing, as long as an ...........................
Heat Pump (including equivalent air
Space-Constrained and conditioner basic
SDHV). model has been tested
If an equivalent air
conditioner basic
model has not been
tested, must test a
model of indoor unit.
Multi-Split, Multi- A model of indoor unit A ``tested combination''
Circuit, or Multi- composed entirely of SDHV
Head Mini-Split Split indoor units, where the
System--SDHV. outdoor unit is the least
efficient model of outdoor
unit with which the SDHV
indoor unit will be
paired. The least
efficient model of outdoor
unit is the model of
outdoor unit in the lowest
SEER combination (when
testing under appendix M
to subpart B of 10 CFR
part 430) or SEER2
combination (when testing
under appendix M1 to
subpart B of 10 CFR part
430) as certified by the
OUM. If there are multiple
models of outdoor unit
with the same lowest SEER
represented value (when
testing under appendix M
to subpart B of 10 CFR
part 430) or SEER2
represented value (when
testing under appendix M1
to subpart B of 10 CFR
part 430), the ICM may
select one for testing
purposes.
Outdoor Unit with No Match......... ...................... The model of outdoor A model of coil-only indoor
unit. unit meeting the
requirements of section
2.2e of appendix M or M1
to subpart B of 10 CFR
part 430.
----------------------------------------------------------------------------------------------------------------
[[Page 64586]]
* * * * *
0
3. Section 429.102 is amended by revising paragraphs (c)(4)(i) and
(iii) to read as follows:
Sec. 429.102 Prohibited acts subjecting persons to enforcement
action.
* * * * *
(c) * * *
(4) * * *
(i) A complete central air conditioning system that is not
certified as a complete system that meets the applicable standard.
Combinations that were previously validly certified may be installed
after the manufacturer has discontinued the combination, provided all
combinations within the basic model, including for single-split-system
AC with single-stage or two-stage compressor at least one coil-only
combination as specified in paragraph (a)(1) of this section, comply
with the regional standard applicable at the time of installation.
* * * * *
(iii) An outdoor unit that is part of a certified combination rated
less than the standard applicable in the region in which it is
installed or, where applicable, an outdoor unit with no certified coil-
only combination as specified in paragraph (a)(1) of this section that
meets the standard applicable in the region in which it is installed.
Sec. 429.158 [Amended]
0
4. Section 429.158 is amended by removing ``Sec. 429.102(c)'' in
paragraphs (a) and (b) and adding in its place ``Sec.
429.102(a)(10)''.
PART 430--ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS
0
5. The authority citation for part 430 continues to read as follows:
Authority: 42 U.S.C. 6291-6309; 28 U.S.C. 2461 note.
0
6. Section 430.2 is amended by revising the definition for ``Central
air conditioner or central air conditioning heat pump'' to read as
follows:
Sec. 430.2 Definitions.
* * * * *
Central air conditioner or central air conditioning heat pump means
a product, other than a packaged terminal air conditioner, packaged
terminal heat pump, single-phase single-package vertical air
conditioner with cooling capacity less than 65,000 Btu/h, single-phase
single-package vertical heat pump with cooling capacity less than
65,000 Btu/h, computer room air conditioner, or unitary dedicated
outdoor air system as these equipment categories are defined at 10 CFR
431.92, which is powered by single phase electric current, air cooled,
rated below 65,000 Btu per hour, not contained within the same cabinet
as a furnace, the rated capacity of which is above 225,000 Btu per
hour, and is a heat pump or a cooling unit only. A central air
conditioner or central air conditioning heat pump may consist of: A
single-package unit; an outdoor unit and one or more indoor units; an
indoor unit only; or an outdoor unit with no match. In the case of an
indoor unit only or an outdoor unit with no match, the unit must be
tested and rated as a system (combination of both an indoor and an
outdoor unit). For all central air conditioner and central air
conditioning heat pump-related definitions, see appendix M or M1 of
subpart B of this part.
* * * * *
0
7. Section 430.32 is amended by revising paragraph (c)(6)(ii) to read
as follows:
Sec. 430.32 Energy and water conservation standards and their
compliance dates.
* * * * *
(c) * * *
(6) * * *
(ii) Any model of outdoor unit that has a certified combination
with a rating below the applicable standard level(s) for a region
cannot be installed in that region. The least-efficient combination of
each basic model, which for single-split-system air conditioner (AC)
with single-stage or two-stage compressor (including space-constrained
and small-duct high velocity systems (SDHV)) must be a coil-only
combination, must comply with the applicable standard. See 10 CFR
429.16(a)(1) and (a)(4)(i).
* * * * *
0
8. Appendix M to subpart B of part 430 is amended by:
0
a. Revising the Note;
0
b. Revising the definition of ``nominal capacity'' in section 1.2;
0
c. Revising paragraph a. in section 3.6.4;
0
d. Revising section 4.1.4.2;
0
e. Revising the introductory text to section 4.2.3;
0
f. Revising the equations following the word ``Where:'' in section
4.2.3.3; and
0
g. Revising section 4.2.3.4.
The revisions read as follows:
Appendix M to Subpart B of Part 430--Uniform Test Method for Measuring
the Energy Consumption of Central Air Conditioners and Heat Pumps
Note: Prior to January 1, 2023, if using the appendix M test
procedure for representations, including compliance certifications,
with respect to the energy use, power, or efficiency of central air
conditioners and central air conditioning heat pumps, any such
representations must be based on the results of testing pursuant to
either this appendix or the procedures in appendix M as it appeared
at 10 CFR part 430, subpart B, in the 10 CFR parts 200 to 499
edition revised as of January 1, 2022. Any representations made with
respect to the energy use or efficiency of such central air
conditioners and central air conditioning heat pumps must be in
accordance with whichever version is selected. Any representations,
including compliance certifications, made with respect to the energy
use, power, or efficiency of central air conditioners and central
air conditioning heat pumps made on or after January 1, 2023, must
be based on the results of testing pursuant the procedures in
appendix M1 to this subpart.
* * * * *
1. * * *
1.2 Definitions
* * * * *
Nominal capacity means the capacity that is claimed by the
manufacturer on the product name plate. Nominal cooling capacity is
approximate to the air conditioner cooling capacity tested at A or
A2 condition. Nominal heating capacity is approximate to
the heat pump heating capacity tested in H1N test.
* * * * *
3. * * *
3.6.4 Tests for a Heat Pump Having a Variable-Speed Compressor
a. Conduct one maximum temperature test (H01), two
high temperature tests (H1N and H11), one
frost accumulation test (H2V), and one low temperature
test (H32). Conducting one or both of the following tests
is optional: An additional high temperature test (H12)
and an additional frost accumulation test (H22). If
desired, conduct the optional maximum temperature cyclic
(H0C1) test to determine the heating mode cyclic-
degradation coefficient, CD\h\. If this optional test is
conducted but yields a tested CD\h\ that exceeds the
default CD\h\ or if the optional test is not conducted,
assign CD\h\ the default value of 0.25. Test conditions
for the eight tests are specified in Table 14 to this appendix. The
compressor shall operate at the same heating full speed, measured by
RPM or power input frequency (Hz), for the H12,
H22 and H32 tests. For a cooling/heating heat
pump, the compressor shall operate for the H1N test at a
speed, measured by RPM or power input frequency (Hz), no lower than
the speed used in the A2 test if the tested
H1N heating capacity is less than the tested
A2 cooling capacity. The compressor shall operate at the
same heating minimum speed, measured by RPM or power input frequency
(Hz), for the H01, H1C1, and H11
tests. Determine the heating intermediate compressor speed cited in
Table 14 using the heating mode full and minimum compressors speeds
and:
[[Page 64587]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.013
Where a tolerance on speed of plus 5 percent or the next higher
inverter frequency step from the calculated value is allowed.
* * * * *
4. * * *
4.1.4.2 Unit Operates at an Intermediate Compressor Speed (k=i) In
Order To Match the Building Cooling Load at Temperature Tj,
Qc\k=1\(Tj) < BL(Tj) <
Qc\k=2\(Tj)
[GRAPHIC] [TIFF OMITTED] TR25OC22.014
[GRAPHIC] [TIFF OMITTED] TR25OC22.015
Where:
Qc\k=i\(Tj) = BL(Tj), the space
cooling capacity delivered by the unit in matching the building load
at temperature Tj, Btu/h. The matching occurs with the
unit operating at compressor speed k=i.
[GRAPHIC] [TIFF OMITTED] TR25OC22.016
EER\k=i\(Tj) = the steady-state energy efficiency ratio
of the test unit when operating at a compressor speed of k=i and
temperature Tj, Btu/h per W.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 19 to this appendix. For each
temperature bin where the unit operates at an intermediate
compressor speed, determine the energy efficiency ratio
EER\k=i\(Tj) using, EERk=i(Tj) = A + B Tj + C * T2j.
For each unit, determine the coefficients A, B, and C by
conducting the following calculations once:
[GRAPHIC] [TIFF OMITTED] TR25OC22.017
Where:
T1 = the outdoor temperature at which the unit, when
operating at minimum compressor speed, provides a space cooling
capacity that is equal to the building load
(Qc\k=l\(Tl) = BL(T1)), [deg]F.
Determine T1 by equating Equations 4.1.3-1 and 4.1-2 to
this appendix and solving for outdoor temperature.
Tv = the outdoor temperature at which the unit, when
operating at the intermediate compressor speed used during the
section 3.2.4 Ev test of this appendix, provides a space
cooling capacity that is equal to the building load
(Qc\k=v\(Tv) = BL(Tv)), [deg]F.
Determine Tv by equating Equations 4.1.4-3 and 4.1-2 to
this appendix and solving for outdoor temperature.
T2 = the outdoor temperature at which the unit, when
operating at full compressor speed, provides a space cooling
capacity that is equal to the building load
(Qc\k=2\(T2) = BL(T2)), [deg]F.
Determine T2 by equating Equations 4.1.3-3 and 4.1-2 to
this appendix and solving for outdoor temperature.
[GRAPHIC] [TIFF OMITTED] TR25OC22.018
[[Page 64588]]
* * * * *
4.2.3 Additional Steps for Calculating the HSPF of a Heat Pump Having a
Two-Capacity Compressor
The calculation of the Equation 4.2-1 to this appendix
quantities differ depending upon whether the heat pump would operate
at low capacity (section 4.2.3.1 of this appendix), cycle between
low and high capacity (section 4.2.3.2 of this appendix), or operate
at high capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in
responding to the building load. For heat pumps that lock out low
capacity operation at low outdoor temperatures, the outdoor
temperature at which the unit locks out must be that specified by
the manufacturer in the certification report so that the appropriate
equations can be selected.
* * * * *
4.2.3.3 Heat Pump Only Operates at High (k=2) Compressor Capacity at
Temperature Tj and Its Capacity Is Greater Than the Building
Heating Load, BL(Tj) < Qh\k=2\(Tj)
* * * * *
XK=2(TJ) = BL(Tj/Qk=2h(Tj); and
PLFj = 1-ChD (k = 2) * [1-Xk=2(Tj)].
* * * * *
4.2.3.4 Heat Pump Must Operate Continuously at High (k=2) Compressor
Capacity at Temperature Tj, BL(Tj) =
Qh\k=2\(Tj)
[GRAPHIC] [TIFF OMITTED] TR25OC22.019
Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.020
* * * * *
0
9. Appendix M1 to subpart B of part 430 is amended by:
0
a. Adding a Note;
0
b. Adding in alphabetical order definitions for ``Variable-speed
communicating coil-only central air conditioner or heat pump'' and
``Variable-speed non-communicating coil-only central air conditioner or
heat pump'' in section 1.2;
0
c. Revising paragraph (B) and the undesignated paragraph following it
and adding a second undesignated paragraph in section 2;
0
d. Revising section 3.1.2;
0
e. Revising paragraphs a. and b. in section 3.1.4.1.1;
0
f. Revising paragraphs a. and b. and adding paragraph f. in section
3.1.4.2:
0
g. Revising paragraph b. and adding paragraph d. in section 3.1.4.3;
0
h. Revising paragraph a. in section 3.1.4.4.3;
0
i. Adding paragraph d. in section 3.1.4.6;
0
j. Revising section 3.1.4.7;
0
k. Revising paragraph a., adding paragraph d. immediately following
paragraph c., and revising Table 8 in section 3.2.4;
0
l. Revising paragraph d., redesignating paragraph e. as paragraph f.,
and adding a new paragraph e. in section 3.3;
0
m. Revising the introductory text, redesignating paragraphs a. and b.
as paragraphs c. and d., respectively, adding new paragraphs a. and b.,
and revising newly redesignated paragraph c. in section 3.5.1;
0
n. Revising Table 11 in section 3.6.1;
0
o. Revising Table 12 in section 3.6.2;
0
p. Revising Table 13 in section 3.6.3;
0
q. Revising section 3.6.4 and adding sections 3.6.4.1 and 3.6.4.2;
0
r. Revising Table 15 in section 3.6.6;
0
s. Revising paragraph c., redesignating paragraphs d. and e. as
paragraphs e. and f., respectively, and adding new paragraph d. in
section 3.7;
0
t. Revising paragraph b. in section 3.8;
0
u. Revising paragraph b. in section 3.9.1;
0
v. Revising section 4.1.4;
0
w. Adding sections 4.1.4.2.1 and 4.1.4.2.2;
0
x. Revising the undesignated text after Table 20 and before paragraph
a., including Equation 4.2-2, in section 4.2;
0
y. Revising the introductory text for section 4.2.3;
0
z. Revising section 4.2.3.4;
0
aa. Revising paragraphs a., b., c., and e., in section 4.2.4;
0
bb. Revising sections 4.2.4.1 and 4.2.4.2; and
0
cc. Removing the language ``and X\k=3\(Tj) =
X\k=2\(Tj)'' and adding in its place ``and
X\k=3\(Tj) = 1-X\k=2\(Tj)'' in section 4.2.6.5.
The revisions and additions read as follows:
Appendix M1 to Subpart B of Part 430--Uniform Test Method for Measuring
the Energy Consumption of Central Air Conditioners and Heat Pumps
Note: On or after January 1, 2023, and prior to April 24, 2023,
any representations, including compliance certifications, made with
respect to the energy use, power, or efficiency of central air
conditioners and central air conditioning heat pumps must be based
on the results of testing pursuant to either this appendix or the
procedures in appendix M1 as it appeared at 10 CFR part 430, subpart
B, in the 10 CFR parts 200 to 499 edition revised as of January 1,
2022.
[[Page 64589]]
Any representations made with respect to the energy use or
efficiency of such central air conditioners and central air
conditioning heat pumps must be in accordance with whichever version
is selected.
On or after April 24, 2023, any representations, including
compliance certifications, made with respect to the energy use,
power, or efficiency of central air conditioners and central air
conditioning heat pumps must be based on the results of testing
pursuant to this appendix.
* * * * *
1.2 Definitions
* * * * *
Variable-speed communicating coil-only central air conditioner
or heat pump means a variable-speed compressor system having a coil-
only indoor unit that is installed with a control system that:
(a) Communicates the difference in space temperature and space
setpoint temperature (not a setpoint value inferred from on/off
thermostat signals) to the control that sets compressor speed;
(b) Provides a signal to the indoor fan to set fan speed
appropriate for compressor staging; and
(c) Has installation instructions indicating that the control
system having these capabilities must be installed.
* * * * *
Variable-speed non-communicating coil-only central air
conditioner or heat pump means a variable-speed compressor system
having a coil-only indoor unit that is does not meet the definition
of variable-speed communicating coil-only central air conditioner or
heat pump.
* * * * *
2 Testing Overview and Conditions
* * * * *
(B) For systems other than VRF, only a subset of the sections
listed in this test procedure apply when testing and determining
represented values for a particular unit. Table 1 to this appendix
shows the sections of the test procedure that apply to each system.
Table 1 is meant to assist manufacturers in finding the appropriate
sections of the test procedure. Manufacturers are responsible for
determining which sections apply to each unit tested based on the
model characteristics. The appendix sections provide the specific
requirements for testing. To use Table 1, first refer to the
sections listed under ``all units''. Then refer to additional
requirements based on:
(1) System configuration(s),
(2) The compressor staging or modulation capability, and
(3) Any special features.
Testing requirements for space-constrained products do not
differ from similar products that are not space-constrained, and
thus space-constrained products are not listed separately in Table
1. Air conditioners and heat pumps are not listed separately in
Table 1, but heating procedures and calculations apply only to heat
pumps.
The ``manufacturer's published instructions,'' as stated in
Section 8.2 of ANSI/ASHRAE Standard 37-2009 (incorporated by
reference, see Sec. 430.3) and ``manufacturer's installation
instructions'' discussed in this appendix mean the manufacturer's
installation instructions that come packaged with the unit or appear
in the labels applied to the unit. Manufacturer's installation
instructions do not include online manuals. Installation
instructions that appear in the labels applied to the unit shall
take precedence over installation instructions that come packaged
with the unit.
* * * * *
3.1.2 Manufacturer-Provided Equipment Overrides
Where needed, the manufacturer must provide a means for
overriding the controls of the test unit so that the compressor(s)
operates at the specified speed or capacity and the indoor blower
operates at the specified speed or delivers the specified air volume
rate. For variable-speed non-communicating coil-only air
conditioners and heat pumps, the control system shall be provided
with a control signal indicating operation at high or low stage,
rather than testing with the compressor speed fixed at specific
speeds, with the exception that compressor speed override may be
used for heating mode test H12.
* * * * *
3.1.4.1.1 Cooling Full-Load Air Volume Rate for Ducted Units
* * * * *
a. For all ducted blower-coil systems, except those having a
constant-air-volume-rate indoor blower:
Step (1) Operate the unit under conditions specified for the A
test (for single-stage units) or A2 test (for non-single-
stage units) using the certified fan speed or controls settings, and
adjust the exhaust fan of the airflow measuring apparatus to achieve
the certified cooling full-load air volume rate;
Step (2) Measure the external static pressure;
Step (3) If this external static pressure is equal to or greater
than the applicable minimum external static pressure cited in Table
4 to this appendix, the pressure requirement is satisfied; proceed
to step 7 of this section. If this external static pressure is not
equal to or greater than the applicable minimum external static
pressure cited in Table 4, proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until the first to
occur of:
(i) The applicable Table 4 to this appendix minimum is equaled
or
(ii) The measured air volume rate equals 90 percent or less of
the cooling full-load air volume rate;
Step (5) If the conditions of step 4 (i) of this section occur
first, the pressure requirement is satisfied; proceed to step 7 of
this section. If the conditions of step 4 (ii) of this section occur
first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor
blower (e.g., next highest fan motor pin setting, next highest fan
motor speed) and repeat the evaluation process beginning at step 1
of this section. If the indoor blower setup cannot be further
changed, increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until the applicable
Table 4 to this appendix minimum is equaled; proceed to step 7 of
this section;
Step (7) The airflow constraints have been satisfied. Use the
measured air volume rate as the cooling full-load air volume rate.
Use the final indoor fan speed or control settings of the unit under
test for all tests that use the cooling full-load air volume rate.
Adjust the fan of the airflow measurement apparatus if needed to
obtain the same full-load air volume rate (in scfm) for all such
tests, unless the system modulates indoor blower speed with outdoor
dry bulb temperature or to adjust the sensible to total cooling
capacity ratio--in this case, use an air volume rate that represents
a normal installation and calculate the target external static
pressure as described in section 3.1.4.2 of this appendix.
b. For ducted blower-coil systems with a constant-air-volume-
rate indoor blower. For all tests that specify the cooling full-load
air volume rate, obtain an external static pressure as close to (but
not less than) the applicable Table 4 to this appendix value that
does not cause either automatic shutdown of the indoor blower or a
value of air volume rate variation QVar, defined as
follows, that is greater than 10 percent.
[GRAPHIC] [TIFF OMITTED] TR25OC22.021
Where:
Qmax = maximum measured airflow value
Qmin = minimum measured airflow value
QVar = airflow variance, percent
Additional test steps as described in section 3.3.f of this
appendix are required if the measured external static pressure
exceeds the target value by more than 0.03 inches of water.
* * * * *
3.1.4.2 Cooling Minimum Air Volume Rate
* * * * *
a. For a ducted blower-coil system without a constant-air-volume
indoor blower, adjust for external static pressure as follows:
Step (1) Operate the unit under conditions specified for the
B1 test using the certified fan speed or controls
settings, and adjust the exhaust fan of the airflow measuring
apparatus to achieve the certified cooling minimum air volume rate;
Step (2) Measure the external static pressure;
Step (3) If this pressure is equal to or greater than the
minimum external static pressure computed in step 2 of this section,
the pressure requirement is satisfied; proceed to step 7 of this
section. If this pressure is not equal to or greater than the
minimum external static pressure computed in step 2 of this section,
proceed to step 4 of this section;
Step (4) Increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until either:
[[Page 64590]]
(i) The pressure is equal to the target minimum external static
pressure, [Delta]Pst_i, computed in step 1 of this
section; or
(ii) The measured air volume rate equals 90 percent or less of
the cooling minimum air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur
first, the pressure requirement is satisfied; proceed to step 7 of
this section. If the conditions of step 4 (ii) of this section occur
first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor
blower (e.g., next highest fan motor pin setting, next highest fan
motor speed) and repeat the evaluation process beginning at step 1
of this section. If the indoor blower setup cannot be further
changed, increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until it equals the
minimum external static pressure computed in step 2 of this section;
proceed to step 7 of this section;
Step (7) The airflow constraints have been satisfied. Use the
measured air volume rate as the cooling minimum air volume rate. Use
the final indoor fan speed or control settings of the unit under
test for all tests that use the cooling minimum air volume rate.
Adjust the fan of the airflow measurement apparatus if needed to
obtain the same cooling minimum air volume rate (in scfm) for all
such tests, unless the system modulates the indoor blower speed with
outdoor dry bulb temperature or to adjust the sensible to total
cooling capacity ratio--in this case, use an air volume rate that
represents a normal installation and calculate the target minimum
external static pressure as described in this section.
b. For ducted units with constant-air-volume indoor blowers,
conduct all tests that specify the cooling minimum air volume rate--
(i.e., the A1, B1, C1,
F1, and G1 Tests)--at an external static
pressure that does not cause either an automatic shutdown of the
indoor blower or a value of air volume rate variation
QVar, defined in section 3.1.4.1.1.b of this appendix,
that is greater than 10 percent, while being as close to, but not
less than the target minimum external static pressure. Additional
test steps as described in section 3.3.f of this appendix are
required if the measured external static pressure exceeds the target
value by more than 0.03 inches of water.
* * * * *
f. For ducted variable-speed compressor systems tested with a
coil-only indoor unit, the cooling minimum air volume rate is the
higher of:
(1) The rate specified by the installation instructions included
with the unit by the manufacturer; or
(2) 75 percent of the cooling full-load air volume rate. During
the laboratory tests on a coil-only (fanless) system, obtain this
cooling minimum air volume rate regardless of the pressure drop
across the indoor coil assembly.
3.1.4.3 Cooling Intermediate Air Volume Rate
* * * * *
b. For a ducted blower-coil system with a constant-air-volume
indoor blower, conduct the EV Test at an external static
pressure that does not cause either an automatic shutdown of the
indoor blower or a value of air volume rate variation
QVar, defined in section 3.1.4.1.1.b of this appendix,
that is greater than 10 percent, while being as close to, but not
less than the target minimum external static pressure. Additional
test steps as described in section 3.3.f of this appendix are
required if the measured external static pressure exceeds the target
value by more than 0.03 inches of water.
* * * * *
d. For ducted variable-speed compressor systems tested with a
coil-only indoor unit, use the cooling minimum air volume rate as
determined in section 3.1.4.2(f) of this appendix, without regard to
the pressure drop across the indoor coil assembly.
* * * * *
3.1.4.4.3 Ducted Heating-Only Heat Pumps
* * * * *
a. For all ducted heating-only blower-coil system heat pumps,
except those having a constant-air-volume-rate indoor blower:
conduct the following steps only during the first test, the H1 or
H12 test:
Step (1) Adjust the exhaust fan of the airflow measuring
apparatus to achieve the certified heating full-load air volume
rate.
Step (2) Measure the external static pressure.
Step (3) If this pressure is equal to or greater than the Table
4 to this appendix minimum external static pressure that applies
given the heating-only heat pump's rated heating capacity, the
pressure requirement is satisfied; proceed to step 7 of this
section. If this pressure is not equal to or greater than the
applicable Table 4 minimum external static pressure, proceed to step
4 of this section;
Step (4) Increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until either:
(i) The pressure is equal to the applicable Table 4 to this
appendix minimum external static pressure; or
(ii) The measured air volume rate equals 90 percent or less of
the heating full-load air volume rate, whichever occurs first;
Step (5) If the conditions of step 4 (i) of this section occur
first, the pressure requirement is satisfied; proceed to step 7 of
this section. If the conditions of step 4 (ii) of this section occur
first, proceed to step 6 of this section;
Step (6) Make an incremental change to the setup of the indoor
blower (e.g., next highest fan motor pin setting, next highest fan
motor speed) and repeat the evaluation process beginning at step 1
of this section. If the indoor blower setup cannot be further
changed, increase the external static pressure by adjusting the
exhaust fan of the airflow measuring apparatus until it equals the
applicable Table 4 to this appendix minimum external static
pressure; proceed to step 7 of this section;
Step (7) The airflow constraints have been satisfied. Use the
measured air volume rate as the heating full-load air volume rate.
Use the final indoor fan speed or control settings of the unit under
test for all tests that use the heating full-load air volume rate.
Adjust the fan of the airflow measurement apparatus if needed to
obtain the same heating full-load air volume rate (in scfm) for all
such tests, unless the system modulates indoor blower speed with
outdoor dry bulb temperature--in this case, use an air volume rate
that represents a normal installation and calculate the target
minimum external static pressure as described in section 3.1.4.2 of
this appendix.
* * * * *
3.1.4.6 Heating Intermediate Air Volume Rate
* * * * *
d. For ducted variable-speed compressor systems tested with a
coil-only indoor unit, use the heating minimum air volume rate,
which (as specified in section 3.1.4.5.1.a.(3) of this appendix) is
equal to the cooling minimum air volume rate, without regard to the
pressure drop across the indoor coil assembly.
3.1.4.7 Heating Nominal Air Volume Rate
The manufacturer must specify the heating nominal air volume
rate and the instructions for setting fan speed or controls.
Calculate target minimum external static pressure as described in
section 3.1.4.2 of this appendix. Make adjustments as described in
section 3.1.4.6 of this appendix for heating intermediate air volume
rate so that the target minimum external static pressure is met or
exceeded. For ducted variable-speed compressor systems tested with a
coil-only indoor unit, use the heating full-load air volume rate as
the heating nominal air volume rate.
* * * * *
3.2.4 Tests for a Unit Having a Variable-Speed Compressor
a. Conduct five steady-state wet coil tests: the A2,
EV, B2, B1, and F1 Tests
(the EV test is not applicable for variable speed non-
communicating coil-only air conditioners and heat pumps). Use the
two optional dry-coil tests, the steady-state G1 Test and
the cyclic I1 Test, to determine the cooling mode cyclic
degradation coefficient, CD\c\. If the two optional tests
are conducted and yield a tested CD\c\ that exceeds the
default CD\c\ or if the two optional tests are not
conducted, assign CD\c\ the default value of 0.25. Table
8 specifies test conditions for these seven tests. The compressor
shall operate at the same cooling full speed, measured by RPM or
power input frequency (Hz), for both the A2 and
B2 tests. The compressor shall operate at the same
cooling minimum speed, measured by RPM or power input frequency
(Hz), for the B1, F1, G1, and
I1 tests. Determine the cooling intermediate compressor
speed cited in Table 8 to this appendix, as required, using:
[[Page 64591]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.022
Where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed.
* * * * *
d. For variable-speed non-communicating coil-only air
conditioners and heat pumps, the manufacturer-provided equipment
overrides for full and minimum compressor speed described in section
3.1.2 of this appendix shall be limited to two stages of digital on/
off control.
Table 8--Cooling Mode Test Condition for Units Having a Variable-Speed Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F)
Test description ---------------------------------------------------------------- Compressor speed Cooling air volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
A2 Test--required (steady, wet coil). 80 67 95 \1\75 Cooling Full............ Cooling Full-Load.\2\
B2 Test--required (steady, wet coil). 80 67 82 \1\65 Cooling Full............ Cooling Full-Load.\2\
EV Test--required \7\ (steady, wet 80 67 87 \1\69 Cooling Intermediate.... Cooling
coil). Intermediate.\3\
B1 Test--required (steady, wet coil). 80 67 82 \1\65 Cooling Minimum......... Cooling Minimum.\4\
F1 Test--required (steady, wet coil). 80 67 67 \1\53.5 Cooling Minimum......... Cooling Minimum.\4\
G1 Test \5\--optional (steady, dry- 80 (\6\) 67 .............. Cooling Minimum......... Cooling Minimum.\4\
coil).
I1 Test \5\--optional (cyclic, dry- 80 (\6\) 67 .............. Cooling Minimum......... (\6\)
coil).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ The specified test condition only applies if the unit rejects condensate to the outdoor coil.
\2\ Defined in section 3.1.4.1 of this appendix.
\3\ Defined in section 3.1.4.3 of this appendix.
\4\ Defined in section 3.1.4.2 of this appendix.
\5\ The entering air must have a low enough moisture content so no condensate forms on the indoor coil. DOE recommends using an indoor air wet bulb
temperature of 57 [deg]F or less.
\6\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure difference or velocity
pressure as measured during the G1 Test.
\7\ The EV test is not applicable for variable-speed non-communicating coil-only air conditioners and heat pumps.
* * * * *
3.3 Test Procedures for Steady-State Wet Coil Cooling Mode Tests (the
A, A2, A1, B, B2, B1,
EV, and F1 Tests)
* * * * *
d. For mobile home and space-constrained ducted coil-only system
tests,
(1) For two-stage or variable-speed systems, for all steady-
state wet coil tests (i.e., the A1, A2,
B1, B2, EV, and F1
tests), decrease by the quantity calculated in Equation 3.3-1 to
this appendix and increase by the quantity calculated in Equation
3.3-2 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.023
Where:
DFPCMHSC is the default fan power coefficient (watts) for
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.024
[[Page 64592]]
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the A2
and B2 tests), set %FLAVR to 100%. For tests that specify
the cooling minimum air volume rate or cooling intermediate air
volume rate (i.e., the A1, B1, EV,
and F1 tests) and for which the specified minimum or
intermediate air volume rate is greater than or equal to 75 percent
of the cooling full-load air volume rate and less than the cooling
full-load air volume rate, set %FLAVR to the ratio of the specified
air volume rate and the cooling full-load air volume rate, expressed
as a percentage.
(2) For single-stage systems, for all steady-state wet coil
tests (i.e., the A and B tests), decrease Qc\k\(T) by the
quantity calculated in Equation 3.3-3 to this appendix and increase
Ec\k\(T) by the quantity calculated in Equation 3.3-4 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.025
Where VS is the average measured indoor air volume rate
expressed in units of cubic feet per minute of standard air (scfm).
e. For non-mobile, non-space-constrained home ducted coil-only
system tests,
(1) For two-stage or variable-speed systems, for all steady-
state wet coil tests (i.e., the A1, A2,
B1, B2, EV, and F1
tests), decrease Qc\k\(T) by the quantity calculated in
Equation 3.3-5 to this appendix and increase Ec\k\(T) by
the quantity calculated in Equation 3.3-6 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.026
[GRAPHIC] [TIFF OMITTED] TR25OC22.027
Where:
DFPCC is the default fan power coefficient (watts) for
non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.028
And %FLAVR is the air volume rate used for the test, expressed
as a percentage of the cooling full load air volume rate. For all
tests specifying the full-load air volume rate (e.g., the
A2 and B2 tests), set %FLAVR to 100%. For
tests that specify the cooling minimum air volume rate or cooling
intermediate air volume rate (i.e., the A1,
B1, EV, and F1 tests) and for which
the specified minimum or intermediate air volume rate is greater
than or equal to 75 percent of the cooling full-load air volume rate
and less than the cooling full-load air volume rate, set %FLAVR to
the ratio of the specified air volume rate and the cooling full-load
air volume rate, expressed as a percentage.
(2) For single-stage systems, for all steady-state wet coil
tests (i.e., the A and B tests), decrease Qc\k\(T) by the
quantity calculated in Equation 3.3-7 to this appendix and increase
Ec\k\(T) by the quantity calculated in Equation 3.3-8 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.029
[GRAPHIC] [TIFF OMITTED] TR25OC22.030
Where is the average measured indoor air volume rate expressed in
units of cubic feet per minute of standard air (scfm).
[[Page 64593]]
Table 9--Test Operating and Test Condition Tolerances for Section 3.3
Steady-State Wet Coil Cooling Mode Tests and Section 3.4 Dry Coil
Cooling Mode Tests
------------------------------------------------------------------------
Test operating Test condition
tolerance \1\ tolerance \1\
------------------------------------------------------------------------
Indoor dry-bulb, [deg]F
Entering temperature................ 2.0 0.5
Leaving temperature................. 2.0 ..............
Indoor wet-bulb, [deg]F .............. ..............
Entering temperature................ 1.0 \2\ 0.3
Leaving temperature................. \2\ 1.0 ..............
Outdoor dry-bulb, [deg]F
Entering temperature................ 2.0 0.5
Leaving temperature................. \3\ 2.0 ..............
Outdoor wet-bulb, [deg]F
Entering temperature................ 1.0 \4\ 0.3
Leaving temperature................. \3\ 1.0 ..............
External resistance to airflow, inches 0.05 \5\ 0.02
of water...............................
Electrical voltage, % of reading........ 2.0 1.5
Nozzle pressure drop, % of reading...... 2.0 ..............
------------------------------------------------------------------------
\1\ See section 1.2 of this appendix, Definitions.
\2\ Only applies during wet coil tests; does not apply during steady-
state, dry coil cooling mode tests.
\3\ Only applies when using the outdoor air enthalpy method.
\4\ Only applies during wet coil cooling mode tests where the unit
rejects condensate to the outdoor coil.
\5\ Only applies when testing non-ducted units.
* * * * *
3.5.1 Procedures When Testing Ducted Systems
The automatic controls that are installed in the test unit must
govern the OFF/ON cycling of the air moving equipment on the indoor
side (i.e., the exhaust fan of the airflow measuring apparatus and
the indoor blower of the test unit). For ducted coil-only systems
rated based on using a fan time-delay relay, control the indoor coil
airflow according to the OFF delay listed by the manufacturer in the
certification report. For ducted units having a variable-speed
indoor blower that has been disabled (and possibly removed), start
and stop the indoor airflow at the same instances as if the fan were
enabled. For all other ducted coil-only systems, cycle the indoor
coil airflow in unison with the cycling of the compressor. If air
damper boxes are used, close them on the inlet and outlet side
during the OFF period. Airflow through the indoor coil should stop
within 3 seconds after the automatic controls of the test unit de-
energize (or if the airflow system has been disabled (and possibly
removed), within 3 seconds after the automatic controls of the test
unit would have de-energized) the indoor blower.
a. For mobile home and space-constrained ducted coil-only
systems,
(1) For two-stage or variable-speed systems, for all cyclic dry-
coil tests (i.e., the D1, D2, and
I1 tests) decrease qcyc,dry by the quantity
calculated in Equation 3.5-2 to this appendix and increase
ecyc,dry by the quantity calculated in Equation 3.5-3 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.031
[GRAPHIC] [TIFF OMITTED] TR25OC22.032
Where:
VS is the average indoor air volume rate from the section
3.4 dry coil steady-state test and is expressed in units of cubic
feet per minute of standard air (scfm),
DFPCMHSC is the default fan power coefficient (watts) for
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.033
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the D2
test), set %FLAVR to 100%. For tests that specify the cooling
minimum air volume rate or cooling intermediate air volume rate
(i.e., the D1 and I1 tests) and for which the
specified minimum or intermediate air volume rate is greater than or
equal to 75 percent of the cooling full-load air volume rate and
less than the cooling full-load air volume rate, set %FLAVR to the
ratio of the specified air volume rate and the cooling full-load air
volume rate, expressed as a percentage.
(2) For single-stage systems, for all cyclic dry-coil tests
(i.e., the D test), decrease qcyc,dry by the quantity
calculated in Equation 3.5-4 to this appendix and increase
ecyc,dry by the quantity calculated in Equation 3.5-5 to
this appendix.
[[Page 64594]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.034
[GRAPHIC] [TIFF OMITTED] TR25OC22.035
b. For ducted, non-mobile, non-space-constrained home coil-only
units,
(1) For two-stage or variable-speed systems, for all cyclic dry-
coil tests (i.e., the D1, D2, and
I1 tests) decrease qcyc,dry by the quantity
calculated in Equation 3.5-6 to this appendix and increase
ecyc,dry by the quantity calculated in Equation 3.5-7 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.036
Where:
VS is the average indoor air volume rate from the section
3.4 dry coil steady-state test and is expressed in units of cubic
feet per minute of standard air (scfm),
DFPCC is the default fan power coefficient (watts) for
non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.037
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the D2
test), set %FLAVR to 100%. For tests that specify the cooling
minimum air volume rate or cooling intermediate air volume rate
(i.e., the D1, and I1 tests) and for which the
specified minimum or intermediate air volume rate is greater than or
equal to 75 percent of the cooling full-load air volume rate and
less than the cooling full-load air volume rate, set %FLAVR to the
ratio of the specified air volume rate and the cooling full-load air
volume rate, expressed as a percentage.
(2) For single-stage systems, for all cyclic dry-coil tests
(i.e., the D test) decrease qcyc,dry by the quantity
calculated in Equation 3.5-8 to this appendix and increase
ecyc,dry by the quantity calculated in Equation 3.5-9 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.038
[GRAPHIC] [TIFF OMITTED] TR25OC22.039
c. For units having a variable-speed indoor blower that is
disabled during the cyclic test, decrease qcyc,dry and
increase ecyc,dry based on: The product of
[[tau]2 - [tau]1] and the indoor blower power
(in W) measured during or following the dry coil steady-state test;
or,
* * * * *
3.6.1 Tests for a Heat Pump Having a Single-Speed Compressor and Fixed
Heating Air Volume Rate
* * * * *
Table 11--Heating Mode Test Conditions for Units Having a Single-Speed Compressor and a Fixed-Speed Indoor
Blower, a Constant Air Volume Rate Indoor Blower, or Coil-Only
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F) Heating air
Test description ------------------------------------------------------------------ volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
H1 test (required, steady)... 70 60\(max)\...... 47 43............. Heating Full-
Load.\1\
H1C test (optional, cyclic).. 70 60\(max)\...... 47 43............. (\2\)
H2 test (required)........... 70 60\(max)\...... 35 33............. Heating Full-
Load.\1\
H3 test (required, steady)... 70 60\(max)\...... 17 15............. Heating Full-
Load.\1\
H4 test (optional, steady)... 70 60\(max)\...... 5 4\(max)\....... Heating Full-
Load.\1\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the
same pressure or velocity as measured during the H1 test.
[[Page 64595]]
* * * * *
3.6.2 Tests for a Heat Pump Having a Single-Speed Compressor and a
Single Indoor Unit Having Either (1) a Variable-Speed, Variable-Air-
Rate Indoor Blower Whose Capacity Modulation Correlates With Outdoor
Dry Bulb Temperature or (2) Multiple Indoor Blowers
* * * * *
Table 12--Heating Mode Test Conditions for Units With a Single-Speed Compressor That Meet the Section 3.6.2
Indoor Unit Requirements
----------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F) Heating air
Test description ------------------------------------------------------------------ volume rate
Dry bulb Wet bulb Dry bulb Wet bulb
----------------------------------------------------------------------------------------------------------------
H12 test (required, steady).. 70 60\(max)\...... 47 43............. Heating Full-
Load.\1\
H11 test (required, steady).. 70 60\(max)\...... 47 43............. Heating
Minimum.\2\
H1C1 test (optional, cyclic). 70 60\(max)\...... 47 43............. (\3\)
H22 test (required).......... 70 60\(max)\...... 35 33............. Heating Full-
Load.\1\
H21 test (optional).......... 70 60\(max)\...... 35 33............. Heating
Minimum.\2\
H32 test (required, steady).. 70 60\(max)\...... 17 15............. Heating Full-
Load.\1\
H31 test (required, steady).. 70 60\(max)\...... 17 15............. Heating
Minimum.\2\
H42 test (optional, steady).. 70 60\(max)\...... 5 4\(max)\....... Heating Full-
Load.\1\
----------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.4 of this appendix.
\2\ Defined in section 3.1.4.5 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the
same pressure or velocity as measured during the H11 test.
* * * * *
3.6.3 Tests for a Heat Pump Having a Two-Capacity Compressor (see
Section 1.2 of This Appendix, Definitions), Including Two-Capacity,
Northern Heat Pumps (see Section 1.2 of This Appendix, Definitions)
* * * * *
Table 13--Heating Mode Test Conditions for Units Having a Two-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit Air entering outdoor unit
temperature ([deg]F) temperature ([deg]F) Heating air volume
Test description ------------------------------------------------------------------------ Compressor capacity rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady)....... 70 60\(max)\............ 62 56.5................. Low.................. Heating Minimum.\1\
H12 test (required, steady)....... 70 60\(max)\............ 47 43................... High................. Heating Full-Load.\2\
H1C2 test (optional,\7\ cyclic)... 70 60\(max)\............ 47 43................... High................. (\3\)
H11 test (required, steady)....... 70 60\(max)\............ 47 43................... Low.................. Heating Minimum.\1\
H1C1 test (optional, cyclic)...... 70 60\(max)\............ 47 43................... Low.................. (\4\)
H22 test (required)............... 70 60\(max)\............ 35 33................... High................. Heating Full-Load.\2\
H21 test 5 6 (required)........... 70 60\(max)\............ 35 33................... Low.................. Heating Minimum.\1\
H32 test (required, steady)....... 70 60\(max)\............ 17 15................... High................. Heating Full-Load.\2\
H31 test \5\ (required, steady)... 70 60\(max)\............ 17 15................... Low.................. Heating Minimum.\1\
H42 test (optional, steady)....... 70 60\(max)\............ 5 4\(max)\............. High................. Heating Full-Load.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Defined in section 3.1.4.4 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
during the H12 test.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
during the H11 test.
\5\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37[deg]F is needed to
complete HSPF2 calculations in section 4.2.3 of this appendix.
\6\ If note #5 to this table applies, the equations for Q h\k=1\ (35) and E h\k=1\ (17) in section 3.6.3 of this appendix may be used in lieu of
conducting the H21 test.
\7\ Required only if the heat pump locks out low-capacity operation at lower outdoor temperatures.
[[Page 64596]]
* * * * *
3.6.4 Tests for a Heat Pump Having a Variable-Speed Compressor
3.6.4.1 Variable-Speed Compressor Other Than Non-Communicating Coil-
Only Heat Pumps
a. Conduct one maximum temperature test (H01), two
high temperature tests (H1N and H11), one
frost accumulation test (H2V), and one low temperature
test (H32). Conducting one or more of the following tests
is optional: an additional high temperature test (H12),
an additional frost accumulation test (H22), and a very
low temperature test (H42). Conduct the optional high
temperature cyclic (H1C1) test to determine the heating
mode cyclic-degradation coefficient, CD\h\. If this
optional test is conducted and yields a tested CD\h\ that
exceeds the default CD\h\ or if the optional test is not
conducted, assign CD\h\ the default value of 0.25. Test
conditions for the nine tests are specified in Table 14A to this
appendix. The compressor shall operate for the H12,
H22 and H32 Tests at the same heating full
speed, measured by RPM or power input frequency (Hz), as the maximum
speed at which the system controls would operate the compressor in
normal operation in 17[deg]F ambient temperature. The compressor
shall operate for the H1N test at the maximum speed at
which the system controls would operate the compressor in normal
operation in 47[deg]F ambient temperature. Additionally, for a
cooling/heating heat pump, the compressor shall operate for the
H1N test at a speed, measured by RPM or power input
frequency (Hz), no lower than the speed used in the A2
test if the tested H1N heating capacity is less than the
tested A2 cooling capacity. The compressor shall operate
at the same heating minimum speed, measured by RPM or power input
frequency (Hz), for the H01, H1C1, and
H11 Tests. Determine the heating intermediate compressor
speed cited in Table 14A using the heating mode full and minimum
compressors speeds and:
[GRAPHIC] [TIFF OMITTED] TR25OC22.040
Where a tolerance of plus 5 percent or the next higher inverter
frequency step from that calculated is allowed.
b. If one of the high temperature tests (H12 or
H1N) is conducted using the same compressor speed (RPM or
power input frequency) as the H32 test, set the 47[deg]F
capacity and power input values used for calculation of HSPF2 equal
to the measured values for that test:
Qk=2hcalc(47) = Qk=2h(47);
Ek=2hcalc(47) = E\k=2\h(47)
Where:
Q\k=2\hcalc(47) and E\k=2\hcalc(47) are the capacity and power
input, respectively, representing full-speed operation at 47 [deg]F
for the HSPF2 calculations,
Q\k=2\h(47) is the capacity measured in the high temperature test
(H12 or H1N) that used the same compressor
speed as the H32 test, and
E\k=2\h(47) is the power input measured in the high temperature test
(H12 or H1N) which used the same compressor
speed as the H32 test.
Evaluate the quantities Q\h\k=2(47) and Ehk=2(47)
according to section 3.7 of this appendix.
Otherwise (if no high temperature test is conducted using the
same speed (RPM or power input frequency) as the H32
test), calculate the 47 [deg]F capacity and power input values used
for calculation of HSPF2 as follows:
Q\k=2\hcalc(47) = Q\k=2\h(17) * (1 + 30[deg]F * CSF);
E\k=2\hcalc(47) = E\k=2\h(17) * (1 + 30[deg]F * PSF);
Where:
Q\k=2\hcalc(47) and E\k=2\hcalc(47) are the capacity and power
input, respectively, representing full-speed operation at 47 [deg]F
for the HSPF2 calculations,
Q\k=2\h(17) is the capacity measured in the H32 test,
E\k=2\h(17) is the power input measured in the H32 test,
CSF is the capacity slope factor, equal to 0.0204/[deg]F for split
systems and 0.0262/[deg]F for single-package systems, and
PSF is the Power Slope Factor, equal to 0.00455/[deg]F.
c. If the H22 test is not done, use the following
equations to approximate the capacity and electrical power at the
H22 test conditions:
Q\k=2\h(35) = 0.90*{Q\k=2\h(17) +
0.6*[Q\k=2\hcalc(47) - Q\k=2\h(17)]{time}
E\k=2\h(35) = 0.985*{E\k=2\h(17) +
0.6*[E\k=2\hcalc(47) - E\k=2\h(17)]{time}
Where:
Q\k=2\hcalc(47) and E\k=2\hcalc(47) are the
capacity and power input, respectively, representing full-speed
operation at 47 [deg]F for the HSPF2 calculations, calculated as
described in paragraph b. of this section, and
Q\k=2\h(17) and E\k=2\h(17) are the capacity
and power input measured in the H32 test.
d. Determine the quantities Qh\k=2\(17) and
Eh\k=2\(17) from the H32 test, determine the
quantities Qh\k=2\(5) and Eh\k=2\(5) from the
H42 test, and evaluate all four according to section 3.10
of this appendix.
e. For multiple-split heat pumps (only), the following
procedures supersede the above requirements. For all Table 14A of
this appendix tests specified for a minimum compressor speed, turn
off at least one indoor unit. The manufacturer shall designate the
particular indoor unit(s) to be turned off. The manufacturer must
also specify the compressor speed used for the Table 14A
H2V test, a heating mode intermediate compressor speed
that falls within \1/4\ and \3/4\ of the difference between the full
and minimum heating mode speeds. The manufacturer should prescribe
an intermediate speed that is expected to yield the highest COP for
the given H2V test conditions and bracketed compressor
speed range. The manufacturer can designate that one or more
specific indoor units are turned off for the H2V test.
Table 14A--Heating Mode Test Conditions for Units Having a Variable-Speed Compressor Other Than Variable-Speed Non-Communicating Coil-Only Heat Pumps
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit temperature Air entering outdoor unit
([deg]F) temperature ([deg]F) Heating air volume
Test description ---------------------------------------------------------------------------- Compressor speed rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady)...... 70 60\(max)\........... 62 56.5................ Heating Minimum..... Heating Minimum.\1\
H12 test (optional, steady)...... 70 60\(max)\........... 47 43.................. Heating Full \4\.... Heating Full-
Load.\3\
H11 test (required, steady)...... 70 60\(max)\........... 47 43.................. Heating Minimum..... Heating Minimum.\1\
H1N test (required, steady)...... 70 60\(max)\........... 47 43.................. Heating Full \5\.... Heating Nominal.\7\
H1C1 test (optional, cyclic)..... 70 60\(max)\........... 47 43.................. Heating Minimum..... (\2\)
H22 test (optional).............. 70 60\(max)\........... 35 33.................. Heating Full \4\.... Heating Full-
Load.\3\
H2V test (required).............. 70 60\(max)\........... 35 33.................. Heating Intermediate Heating
Intermediate.\6\
[[Page 64597]]
H32 test (required, steady)...... 70 60\(max)\........... 17 15.................. Heating Full \4\.... Heating Full-
Load.\3\
H42 test (optional, steady)...... 70 60\(max)\........... 5 4\(max)\............ Heating Full \8\.... Heating Full-
Load.\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
during the H11 test.
\3\ Defined in section 3.1.4.4 of this appendix.
\4\ Maximum speed that the system controls would operate the compressor in normal operation in 17[deg]F ambient temperature. The H12 test is not needed
if the H1N test uses this same compressor speed.
\5\ Maximum speed that the system controls would operate the compressor in normal operation in 47[deg]F ambient temperature.
\6\ Defined in section 3.1.4.6 of this appendix.
\7\ Defined in section 3.1.4.7 of this appendix.
\8\ Maximum speed that the system controls would operate the compressor in normal operation at 5[deg]F ambient temperature.
3.6.4.2 Variable-Speed Compressor With Non-Communicating Coil-Only Heat
Pumps
a. Conduct one maximum temperature test (H01), two
high temperature tests (H1N and H11), two
frost accumulation test (H22 and H21), and two
low temperature tests (H32 and H31).
Conducting one or both of the following tests is optional: an
additional high temperature test (H12) and a very low
temperature test (H42). Conduct the optional high
temperature cyclic (H1C1) test to determine the heating
mode cyclic-degradation coefficient, CD\h\. If this
optional test is conducted and yields a tested CD\h\ that
exceeds the default CD\h\ or if the optional test is not
conducted, assign CD\h\ the default value of 0.25. Test
conditions for the ten tests are specified in Table 14B to this
appendix. The compressor shall operate for the H12 and
H32 tests at the same heating full speed, measured by RPM
or power input frequency (Hz), as the maximum speed at which the
system controls would operate the compressor in normal operation in
17 [deg]F ambient temperature. The compressor shall operate for the
H1N test at the maximum speed at which the system
controls would operate the compressor in normal operation in 47
[deg]F ambient temperature. Additionally, for a cooling/heating heat
pump, the compressor shall operate for the H1N test at a
speed, measured by RPM or power input frequency (Hz), no lower than
the speed used in the A2 test if the tested
H1N heating capacity is less than the tested
A2 cooling capacity. The compressor shall operate at the
same heating minimum speed, measured by RPM or power input frequency
(Hz), for the H01, H1C1, and H11
tests.
b. If one of the high temperature tests (H12 or
H1N) is conducted using the same compressor speed (RPM or
power input frequency) as the H32 test, set the 47 [deg]F
capacity and power input values used for calculation of HSPF2 equal
to the measured values for that test:
Qk=2hcalc(47) = Qk=2h(47) = Ek=\2\hcalc(47) = Ek=2h(47)
Where:
Qk=\2\hcalc(47) and Ek=\2\hcalc(47) are the
capacity and power input, respectively, representing full-speed
operation at 47 [deg]F for the HSPF2 calculations,
Qk=2h(47) is the capacity measured in the high
temperature test (H12 or H1N) which used the
same compressor speed as the H32 test, and
Ek=2h(47) is the power input measured in the high
temperature test (H12 or H1N) which used the
same compressor speed as the H32 test.
Evaluate the quantities Qh=\2\(47) and
Ek=\2\(47) according to section 3.7 of this appendix.
Otherwise (if no high temperature test is conducted using the
same speed (RPM or power input frequency) as the H32
test), calculate the 47 [deg]F capacity and power input values used
for calculation of HSPF2 as follows:
Qk=2hcalc(47) = Qk=2h(17) * (1 + 30 [deg]F CSF); and
Ek=2hcalc(47) = Ek=2h(17) * (1 + 30 [deg]F PSF); and
Where:
Qk=2hcalc and Ek=2hcalc(47) are the capacity and power input,
respectively, representing full-speed operation at 47 [deg]F for the
HSPF2 calculations,
Qk=2h is the capacity measured in the H32 test,
Ek=2h(47) is the power input measured in the H32 test,
CSF is the capacity slope factor, equal to 0.0204/ [deg]F for
split systems, and
PSF is the Power Slope Factor, equal to 0.00455/ [deg]F.
c. Determine the quantities Qk=\2\h(17) and
Ek=\2\h(5) from the H32 test, determine the
quantities Qk=\2\h(5) and Ek=\2\h(5) from the
H42 test, and evaluate all four according to section 3.10
of this appendix.
Table 14B--Heating Mode Test Conditions for Variable-Speed Non-Communicating Coil-Only Heat Pumps
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit temperature Air entering outdoor unit
( [deg]F) temperature ( [deg]F) Heating air volume
Test description ---------------------------------------------------------------------------- Compressor speed rate
Dry bulb Wet bulb Dry bulb Wet bulb
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 test (required, steady)...... 70 60 (max)............ 62 56.5................ Heating Minimum..... Heating Minimum.\1\
H12 test (optional, steady)...... 70 60 (max)............ 47 43.................. Heating Full \4\.... Heating Full-
Load.\3\
H11 test (required, steady)...... 70 60 (max)............ 47 43.................. Heating Minimum..... Heating Minimum.\1\
H1N test (required, steady)...... 70 60 (max)............ 47 43.................. Heating Full \5\.... Heating Full-
Load.\3\
H1C1 test (optional, cyclic)..... 70 60 (max)............ 47 43.................. Heating Minimum..... (\2\)
H22 test (required).............. 70 60 (max)............ 35 33.................. Heating Full \6\.... Heating Full-
Load.\3\
H21 test (required).............. 70 60 (max)............ 35 33.................. Heating Minimum \7\. Heating Minimum.\1\
H32 test (required, steady)...... 70 60 (max)............ 17 15.................. Heating Full \4\.... Heating Full-
Load.\3\
H31 test (required, steady)...... 70 60 (max)............ 17 15.................. Heating Minimum \8\. Heating Minimum.\1\
H42 test (optional, steady)...... 70 60 (max)............ 5 4 (max)............. Heating Full \9\.... Heating Full-
Load.\3\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during an ON period at the same pressure or velocity as measured
during the H11 test.
\3\ Defined in section 3.1.4.4 of this appendix.
\4\ Maximum speed that the system controls would operate the compressor in normal operation in 17 [deg]F ambient temperature. The H12 test is not needed
if the H1N test uses this same compressor speed.
\5\ Maximum speed that the system controls would operate the compressor in normal operation in 47 [deg]F ambient temperature.
\6\ Maximum speed that the system controls would operate the compressor in normal operation in 35 [deg]F ambient temperature.
\7\ Minimum speed that the system controls would operate the compressor in normal operation in 35 [deg]F ambient temperature.
\8\ Minimum speed that the system controls would operate the compressor in normal operation in 17 [deg]F ambient temperature.
\9\ Maximum speed that the system controls would operate the compressor in normal operation in 5 [deg]F ambient temperature.
[[Page 64598]]
* * * * *
3.6.6 Heating Mode Tests for Northern Heat Pumps With Triple-Capacity
Compressors
* * * * *
Table 15--Heating Mode Test Conditions for Units With a Triple-Capacity Compressor
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air entering indoor unit ([deg]F) Air entering outdoor unit ([deg]F)
Test description ---------------------------------------------------------------------------- Compressor capacity Heating air volume
Dry bulb Wet bulb Dry bulb Wet bulb rate
--------------------------------------------------------------------------------------------------------------------------------------------------------
H01 Test (required, steady)...... 70 60 (max)............ 62 56.5................ Low................. Heating Minimum.\1\
H12 (required, steady)........... 70 60 (max)............ 47 43.................. High................ Heating Full-
Load.\2\
H1C2 Test (optional,\8\ cyclic... 70 60 (max)............ 47 43.................. High................ (\3\)
H11 Test (required, steady)...... 70 60 (max)............ 47 43.................. Low................. Heating Minimum.\1\
H1C1 Test (optional, cyclic)..... 70 60 (max)............ 47 43.................. Low................. (\4\)
H23 Test (optional, steady)...... 70 60 (max)............ 35 33.................. Booster............. Heating Full-
Load.\2\
H22 Test (required).............. 70 60 (max)............ 35 33.................. High................ Heating Full-
Load.\2\
H21 Test (required............... 70 60 (max)............ 35 33.................. Low................. Heating Minimum.\1\
H33 Test (required, steady)...... 70 60 (max)............ 17 15.................. Booster............. Heating Full-
Load.\2\
H3C3 Test 5 6 (optional, cyclic). 70 60 (max)............ 17 15.................. Booster............. (\7\)
H32 Test (required, steady)...... 70 60 (max)............ 17 15.................. High................ Heating Full-
Load.\2\
H31 Test \5\ (required, steady).. 70 60 (max)............ 17 15.................. Low................. Heating Minimum.\1\
H43 Test (required, steady)...... 70 60 (max)............ 5 4 (max)............. Booster............. Heating Full-
Load.\2\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Defined in section 3.1.4.5 of this appendix.
\2\ Defined in section 3.1.4.4 of this appendix.
\3\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H12 test.
\4\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H11 test.
\5\ Required only if the heat pump's performance when operating at low compressor capacity and outdoor temperatures less than 37 [deg]F is needed to
complete the HSPF2 calculations in section 4.2.6 of this appendix.
\6\ If note #5 to this table applies, the equations for Qk=1h(35) and Ek=1h (17) in section 3.6.6 of this appendix may be used in lieu of conducting the
H21 test.
\7\ Maintain the airflow nozzle(s) static pressure difference or velocity pressure during the ON period at the same pressure or velocity as measured
during the H33 test.
\8\ Required only if the heat pump locks out low-capacity operation at lower outdoor temperatures
* * * * *
3.7 Test Procedures for Steady-State Maximum Temperature and High
Temperature Heating Mode Tests (the H01, H1, H12,
H11, and H1N tests)
* * * * *
c. For mobile home and space-constrained ducted coil-only system
tests,
(1) For two-stage or variable-speed systems, for all steady-
state maximum temperature and high temperature tests (i.e., the
H01, H11, H12, and H1N
tests), increase Qck(T) by the quantity calculated in Equation 3.7-1
to this appendix and increase Eick(T) by the quantity calculated in
Equation 3.7-2 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.041
[GRAPHIC] [TIFF OMITTED] TR25OC22.042
Where:
DFPCMHSC is the default fan power coefficient (watts) for
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.043
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the H12
and H1N tests), set %FLAVR to 100%. For tests that
specify the heating minimum air volume rate or heating intermediate
air volume rate (i.e., the H01 and H11 tests)
and for which the specified minimum or intermediate air volume rate
is greater than or equal to 75 percent of the cooling full-load air
volume rate and less than the cooling full-load air volume rate, set
%FLAVR to the ratio of the specified air volume rate and the cooling
full-load air volume rate, expressed as a percentage.
(2) For single-stage systems, for all steady-state maximum
temperature and high temperature tests (i.e., the H1 test), increase
Qck(T) by the quantity calculated in Equation 3.7-3 to this appendix
and increase Eck(T) by the quantity calculated in Equation 3.7-4 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.044
[[Page 64599]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.045
Where VS is the average measured indoor air volume rate expressed in
units of cubic feet per minute of standard air (scfm).
d. For non-mobile, non-space-constrained home ducted coil-only
system tests,
(1) For two-stage or variable-speed systems, for all steady-
state maximum temperature and high temperature tests (i.e., the
H01, H11, H12, and H1N
tests), increase Qck(T) by the quantity calculated in Equation 3.7-5
to this appendix and increase Eck(T) by the quantity calculated in
Equation 3.7-6 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.046
[GRAPHIC] [TIFF OMITTED] TR25OC22.047
Where:
DFPCC is the default fan power coefficient (watts)
for non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.048
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the H12
and H1N tests), set %FLAVR to 100%. For tests that
specify the heating minimum air volume rate or heating intermediate
air volume rate (i.e., the H01 and H11 tests)
and for which the specified minimum or intermediate air volume rate
is greater than or equal to 75 percent of the cooling full-load air
volume rate and less than the cooling full-load air volume rate, set
%FLAVR to the ratio of the specified air volume rate and the cooling
full-load air volume rate, expressed as a percentage.
(2) For single-stage systems, for all steady-state maximum
temperature and high temperature tests (i.e., the H1 test), increase
Qck(T) by the quantity calculated in Equation 3.7-7 to this appendix
and increase Eck(T) by the quantity calculated in Equation 3.7-8 to
this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.049
[GRAPHIC] [TIFF OMITTED] TR25OC22.050
Where VS is the average measured indoor air volume rate
expressed in units of cubic feet per minute of standard air (scfm).
* * * * *
3.8 Test Procedures for the Cyclic Heating Mode Tests (the
H0C1, H1C, H1C1 and H1C2 Tests).
* * * * *
b. For ducted coil-only system heat pumps (excluding the special
case where a variable-speed fan is temporarily removed),
(1) For mobile home and space-constrained ducted coil-only
systems,
(i) For two-stage or variable-speed systems, for all cyclic
heating tests (i.e., the H1C1 and H1C2 tests),
increase qcyc by the amount calculated using Equation
3.5-2 to this appendix. Additionally, increase ecyc by
the amount calculated using Equation 3.5-3 to this appendix.
(ii) For single-stage systems, for all cyclic heating tests
(i.e., the H1C and H1C1 tests), increase qcyc
by the amount calculated using Equation 3.5-4 to this appendix.
Additionally, increase ecyc by the amount calculated
using Equation 3.5-5 to this appendix.
(2) For non-mobile home and non-space-constrained ducted coil-
only systems,
(i) For two-stage or variable-speed systems, for all cyclic
heating tests (i.e., the H1C1 and H1C2 tests),
increase qcyc by the amount calculated using Equation
3.5-6 to this appendix. Additionally, increase ecyc by
the amount calculated using Equation 3.5-7 to this appendix.
(ii) For single-stage systems, for all cyclic heating tests
(i.e., the H1C and H1C1 tests), increase qcyc
by the amount calculated using Equation 3.5-8 to this appendix.
Additionally, increase ecyc by the amount calculated
using Equation 3.5-9 to this appendix.
In making these calculations, use the average indoor air volume
rate (Vs) determined from the section 3.7 of this appendix steady-
state heating mode test conducted at the same test conditions.
* * * * *
3.9.1 Average Space Heating Capacity and Electrical Power Calculations
* * * * *
[[Page 64600]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.051
(1) For mobile home and space-constrained ducted coil-only
system tests,
(i) For two-stage or variable-speed systems, for all frost
accumulation tests (i.e., the H21, H22, and
H2V tests), increase Qhk(35) by the quantity
calculated in Equation 3.9.1-1 to this appendix and increase Ehk
(35) by the quantity calculated in Equation 3.9.1-2 to this
appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.052
[GRAPHIC] [TIFF OMITTED] TR25OC22.053
Where:
DFPCMHSC is the default fan power coefficient (watts) for
mobile-home and space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.054
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the H22
test), set %FLAVR to 100%. For tests that specify the heating
minimum air volume rate or heating intermediate air volume rate
(i.e., the H21 and H2v tests) and for which
the specified minimum or intermediate air volume rate is greater
than or equal to 75 percent of the cooling full-load air volume rate
and less than the cooling full-load air volume rate, set %FLAVR to
the ratio of the specified air volume rate and the cooling full-load
air volume rate, expressed as a percentage.
(ii) For single-stage systems, for all frost accumulation tests
(i.e., the H2 test), increase Qhk(35) by the quantity calculated in
Equation 3.9.1-3 to this appendix and increase Qhk(35) by the
quantity calculated in Equation 3.9.1-4 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.055
[GRAPHIC] [TIFF OMITTED] TR25OC22.056
Where Vs is the average measured indoor air volume rate expressed in
units of cubic feet per minute of standard air (scfm).
(2) For non-mobile home and non-space-constrained ducted coil-
only systems,
(i) For two-stage or variable-speed systems, for all frost
accumulation tests (i.e., the H21, H22, and
H2V tests), increase Qhk(35) by the quantity calculated
in Equation 3.9.1-5 to this appendix and increase Ehk(35) by the
quantity calculated in Equation 3.9.1-6 to this appendix.
[GRAPHIC] [TIFF OMITTED] TR25OC22.057
[GRAPHIC] [TIFF OMITTED] TR25OC22.058
Where:
DFPCC is the default fan power coefficient (watts) for
non-mobile-home and non-space-constrained systems,
[GRAPHIC] [TIFF OMITTED] TR25OC22.059
And %FLAVR is the air volume rate used for the test, expressed as a
percentage of the cooling full load air volume rate. For all tests
specifying the full-load air volume rate (e.g., the H22
test), set %FLAVR to 100%. For tests that specify the heating
minimum air volume rate or heating intermediate air volume rate
(i.e., the H21 and H2v tests) and for which
the specified minimum or intermediate air volume rate is greater
than or equal to 75 percent of the cooling full-load air volume rate
and less than the cooling full-load air volume rate, set %FLAVR to
the ratio of the specified air volume rate and the cooling full-load
air volume rate, expressed as a percentage.
(ii) For single-stage systems, for all frost accumulation tests
(i.e., the H2 test), increase Qhk (35) by the quantity calculated in
Equation 3.9.1-7 to this appendix and increase Ehk (35)
by the quantity calculated in Equation 3.9.1-8 to this appendix.
[[Page 64601]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.060
[GRAPHIC] [TIFF OMITTED] TR25OC22.061
Where Vs is the average measured indoor air volume rate expressed in
units of cubic feet per minute of standard air (scfm).
* * * * *
4.1.4 SEER2 Calculations for an Air Conditioner or Heat Pump Having a
Variable-Speed Compressor
Calculate SEER2 using Equation 4.1-1 to this appendix. Evaluate
the space cooling capacity, Qc\k=1\(Tj), and
electrical power consumption, Ec\k=1\(Tj), of
the test unit when operating at minimum compressor speed and outdoor
temperature Tj.. Use:
[GRAPHIC] [TIFF OMITTED] TR25OC22.062
[GRAPHIC] [TIFF OMITTED] TR25OC22.063
Where Qc\k=1\(82) and [Edot]c\k=1\(82)
are determined from the B1 test, Qc\k=1\(67)
and Ec\k=1\(67) are determined from the F1
test, and all four quantities are calculated as specified in section
3.3 of this appendix. Evaluate the space cooling capacity,
Qc\k=2\(Tj), and electrical power consumption,
[Edot]c\k=2\(Tj), of the test unit when
operating at full compressor speed and outdoor temperature
Tj. Use Equations 4.1.3-3 and 4.1.3-4 to this appendix,
respectively, where Qc\k=2\(95) and
[Edot]ck=2(95) are determined from the A2
test, Qc\k=2\(82) and [Edot]c\k=2\(82) are
determined from the B2 test, and all four quantities are
calculated as specified in section 3.3 of this appendix. For units
other than variable-speed non-communicating coil-only air-
conditioners or heat pumps, calculate the space cooling capacity,
Qc\k=v\(Tj), and electrical power consumption,
[Edot]c\k=v\(Tj), of the test unit when
operating at outdoor temperature Tj and the intermediate
compressor speed used during the section 3.2.4 (and Table 8)
EV test of this appendix using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.064
[GRAPHIC] [TIFF OMITTED] TR25OC22.065
Where Qc\k=v\(87) are determined from the EV
test and calculated as specified in section 3.3 of this appendix.
Approximate the slopes of the k=v intermediate speed cooling
capacity and electrical power input curves, MQ and
ME, as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC22.066
Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.067
Use Equations 4.1.4-1 and 4.1.4-2 to this appendix,
respectively, to calculate Qc\k=1\(87) and
[Edot]c\k=1\(87).
* * * * *
4.1.4.2.1 Units That Are Not Variable-Speed Non-Communicating Coil-Only
Air Conditioners or Heat Pumps
If the unit operates at an intermediate compressor speed (k=i)
in order to match the building cooling load at temperature
Tj, Qc\k=1\(Tj) < BL(Tj)
< Qc\k=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TR25OC22.068
[[Page 64602]]
Where:
Qc\k=i\(Tj) = BL(Tj), the space
cooling capacity delivered by the unit in matching the building load
at temperature Tj, in Btu/h. The matching occurs with the
unit operating at compressor speed k = i.
[GRAPHIC] [TIFF OMITTED] TR25OC22.069
EER\k=i\(Tj) = the steady-state energy efficiency ratio
of the test unit when operating at a compressor speed of k = i and
temperature Tj, Btu/h per W.
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 19 of this section. For each temperature
bin where the unit operates at an intermediate compressor speed,
determine the energy efficiency ratio EER\k=i\(Tj) using
the following equations:
For each temperature bin where Qc\k=1\(Tj)
< BL(Tj) < Qc\k=v\(Tj),
[GRAPHIC] [TIFF OMITTED] TR25OC22.070
For each temperature bin where Qc\k=v\(Tj)
< BL(Tj) < Qc\k=2\(Tj),
[GRAPHIC] [TIFF OMITTED] TR25OC22.071
Where:
EER\k=1\(Tj) is the steady-state energy efficiency ratio
of the test unit when operating at minimum compressor speed and
temperature Tj, in Btu/h per W, calculated using capacity
Qc\k=1\(Tj) calculated using Equation 4.1.4-1
to this appendix and electrical power consumption
[Edot]c\k=1\(Tj) calculated using Equation
4.1.4-2 to this appendix;
EER\k=v\(Tj) is the steady-state energy efficiency ratio
of the test unit when operating at intermediate compressor speed and
temperature Tj, in Btu/h per W, calculated using capacity
Qc\k=v\(Tj) calculated using Equation 4.1.4-3
to this appendix and electrical power consumption
[Edot]c\k=v\(Tj) calculated using Equation
4.1.4-4 to this appendix;
EER\k=2\(Tj) is the steady-state energy efficiency ratio
of the test unit when operating at full compressor speed and
temperature Tj, Btu/h per W, calculated using capacity
Qc\k=2\(Tj) and electrical power consumption
[Edot]c\k=2\(Tj), both calculated as described
in section 4.1.4 of this appendix; and
BL(Tj) is the building cooling load at temperature
Tj, Btu/h.
4.1.4.2.2 Variable-Speed Non-Communicating Coil-Only Air Conditioners
or Heat Pumps
If the unit alternates between high (k=2) and low (k=1)
compressor capacity to satisfy the building cooling load at
temperature Tj, Qc\k=1\(Tj) <
BL(Tj) < Qc\k=2\(Tj).
[GRAPHIC] [TIFF OMITTED] TR25OC22.072
Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.073
the cooling mode, low capacity load factor for temperature bin j
(dimensionless); and X\k=2\ (Tj)= 1 - X\k=1\
(Tj), the cooling mode, high capacity load factor for
temperature bin j (demensionless).
Obtain the fractional bin hours for the cooling season,
nj/N, from Table 19 to this appendix. Obtain
Qc\k=1\(Tj),
[Edot]c\k=1\(Tj),
Qc\k=2\(Tj), and
[Edot]c\k=2\(Tj) as described in section 4.1.4
of this appendix.
* * * * *
4.2 Heating Seasonal Performance Factor 2 (HSPF2) Calculations
* * * * *
Evaluate the building heating load using:
[[Page 64603]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.074
Where:
Tj = the outdoor bin temperature, [deg]F;
Tzl = the zero-load temperature, [deg]F, which varies by
climate region according to Table 20 to this appendix;
C = slope (adjustment) factor, which varies by climate region
according to Table 20 to this appendix. When calculating building
load for a variable-speed compressor system, substitute
CVS for C;
Qc(95 [deg]F) = the cooling capacity at 95 [deg]F
determined from the A or A2 test, Btu/h. For heating-only
heat pump units, replace Qc(95 [deg]F) in Equation 4.2-2
with Qh(47 [deg]F);
Qh(47 [deg]F) = the heating capacity at 47 [deg]F
determined from the H1 test for units having a single-speed
compressor, H12 for units having a two-capacity
compressor, and H1N test for units having a variable-
speed compressor, Btu/h.
* * * * *
4.2.3 Additional Steps for Calculating the HSPF2 of a Heat Pump Having
a Two-Capacity Compressor
The calculation of the Equation 4.2-1 to this appendix
quantities differ depending upon whether the heat pump would operate
at low capacity (section 4.2.3.1 of this appendix), cycle between
low and high capacity (section 4.2.3.2 of this appendix), or operate
at high capacity (sections 4.2.3.3 and 4.2.3.4 of this appendix) in
responding to the building load. For heat pumps that lock out low
capacity operation at low outdoor temperatures, the outdoor
temperature at which the unit locks out must be that specified by
the manufacturer in the certification report so that the appropriate
equations can be selected.
* * * * *
4.2.3.4 Heat Pump Must Operate Continuously at High (k=2) Compressor
Capacity at Temperature Tj, BL(Tj) =
Qh\k=2\(Tj)
[GRAPHIC] [TIFF OMITTED] TR25OC22.075
[GRAPHIC] [TIFF OMITTED] TR25OC22.076
Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.077
4.2.4 Additional Steps for Calculating the HSPF2 of a Heat Pump Having
a Variable-Speed Compressor. Calculate HSPF2 Using Equation 4.2-1
* * * * *
a. Minimum Compressor Speed. For units other than variable-speed
non-communicating coil-only heat pumps, evaluate the space heating
capacity, Qh\k=1\(Tj), and electrical power
consumption, Eh\k=1\(Tj), of the heat pump
when operating at minimum compressor speed and outdoor temperature
Tj using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.078
[GRAPHIC] [TIFF OMITTED] TR25OC22.079
Where Qh\k=1\(62) and Eh\k=1\(62) are
determined from the H01 test, Qh\k=1\(47) and
Eh\k=1\(47) are determined from the H11 test,
and all four quantities are calculated as specified in section 3.7
of this appendix.
For variable-speed non-communicating coil-only heat pumps, when
Tj is greater than or equal to 47 [deg]F, evaluate the
space heating capacity, Qh\k=1\(Tj), and
electrical power consumption,
[Edot]h\k=1\(Tj), of the heat pump when
operating at minimum compressor
[[Page 64604]]
speed as described in Equations 4.2.4-1 and 4.2.4-2 to this
appendix, respectively. When Tj is less than 47 [deg]F,
evaluate the space heating capacity,
Qh\k=1\(Tj), and electrical power consumption,
[Edot]h\k=1\(Tj) using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.080
And
[GRAPHIC] [TIFF OMITTED] TR25OC22.081
Where Qh\k=1\(47) and [Edot]h\k=1\(47) are
determined from the H11 test, and both quantities are
calculated as specified in section 3.7 of this appendix;
Qh\k=1\(35) and [Edot]h\k=1\(35) are
determined from the H21 test, and are calculated as
specified in section 3.9 of this appendix; Qh\k=1\(17)
and [Edot]h\k=1\(17) are determined from the
H31 test, and are calculated as specified in section 3.10
of this appendix; and Qh\k=2\(Tj) and
[Edot]h\k=2\(Tj) are calculated as described
in section 4.2.4.c or 4.2.4.d of this appendix, as appropriate.
b. Minimum Compressor Speed for Minimum-speed-limiting Variable-
speed Heat Pumps. For units other than variable-speed non-
communicating coil-only heat pumps, evaluate the space heating
capacity, Qh\k=1\(Tj), and electrical power
consumption, [Edot]h\k=1\(Tj), of the heat
pump when operating at minimum compressor speed and outdoor
temperature Tj using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.082
And
[[Page 64605]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.083
Where Qh\k=1\(62) and [Edot]h\k=1\(62) are
determined from the H01 test, Qh\k=1\(47) and
[Edot]h\k=1\(47) are determined from the H11
test, and all four quantities are calculated as specified in section
3.7 of this appendix; Qh\k=v\(35) and
[Edot]h\k=v\(35) are determined from the H2v
test and are calculated as specified in section 3.9 of this
appendix; and Qh\k=v\(Tj) and
[Edot]h\k=v\(Tj) are calculated using
Equations 4.2.4-7 and 4.2.4-8 to this appendix, respectively.
For variable-speed non-communicating coil-only heat pumps,
evaluate the space heating capacity,
Qh\k=1\(Tj), and electrical power consumption,
[Edot]h\k=1\(Tj), of the heat pump as
described in section 4.2.4.a of this appendix, using Equations
4.2.4-1, 4.2.4-2, 4.2.4-3, and 4.2.4-4 to this appendix, as
appropriate.
c. Full Compressor Speed for Heat Pumps for which the
H42 test is not conducted. Evaluate the space heating
capacity, Qh\k=2\(Tj), and electrical power
consumption, [Edot]h\k=2\(Tj), of the heat
pump when operating at full compressor speed and outdoor temperature
Tj using:
[GRAPHIC] [TIFF OMITTED] TR25OC22.084
And
[GRAPHIC] [TIFF OMITTED] TR25OC22.085
Determine Qh\k=N\(47) and [Edot]h\k=N\(47)
from the H1N test and the calculations specified in
section 3.7 of this appendix. See section 3.6.4.b of this appendix
regarding determination of the capacity Qhcalc\k=2\(47)
and power input [Edot]hcacl\k=2\(47) used in the HSPF2
calculations to represent the H12 Test. Determine
Qh\k=2\(35) and [Edot]h\k=2\(35) from the
H22 test and the calculations specified in section 3.9 of
this appendix or, if the H22 test is not conducted, by
conducting the calculations specified in section 3.6.4 of this
appendix. Determine Qh\k=2\(17) and
[Edot]h\k=2\(17) from the H32 test and the
methods specified in section 3.10 of this appendix.
* * * * *
e. Intermediate Compressor Speed. For units other than variable-
speed non-communicating coil-only heat pumps, calculate the space
heating capacity, Qh\k=v\(Tj), and electrical
power consumption, [Edot]h\k=v\(Tj), of the
heat pump when operating at outdoor temperature Tj and
the intermediate compressor speed used during the H2V
test in section 3.6.4 of this appendix using:
[[Page 64606]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.086
Where Qh\k=v\(35) and [Edot]h\k=v\(35) are
determined from the H2V test and calculated as specified
in section 3.9 of this appendix. Approximate the slopes of the k=v
intermediate speed heating capacity and electrical power input
curves, MQ and ME, as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC22.087
Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.088
Use Equations 4.2.4-1 and 4.2.4-2 to this appendix,
respectively, to calculate Qh\k=1\(35) and
[Edot]h\k=1\(35), whether or not the heat pump is a
minimum-speed-limiting variable-speed heat pump.
For variable-speed non-communicating coil-only heat pumps, there
is no intermediate speed.
4.2.4.1 Steady-State Space Heating Capacity When Operating at Minimum
Compressor Speed is Greater Than or Equal to the Building Heating Load
at Temperature Tj, Qh\k=1\(Tj
=BL(Tj).
Evaluate the Equation 4.2-1 to this appendix quantities:
[GRAPHIC] [TIFF OMITTED] TR25OC22.089
As specified in section 4.2.3.1 of this appendix. Except now use
Equations 4.2.4-1 and 4.2.4-2 (for heat pumps that are not minimum-
speed-limiting and are not variable-speed non-communicating coil-
only heat pumps), Equations 4.2.4-1, 4.2.4-2, 4.2.4-3, and 4.2.4-4
as appropriate (for variable-speed non-communicating coil-only heat
pumps), or Equations 4.2.4-5 and 4.2.4.-6 (for minimum-speed-
limiting variable-speed heat pumps that are not variable-speed non-
communicating coil-only heat pumps) to this appendix to evaluate
Qh\k=1\(Tj) and
[Edot]h\k=1\(Tj), respectively, and replace
section 4.2.3.1 references to ``low capacity'' and section 3.6.3 of
this appendix with ``minimum speed'' and section 3.6.4 of this
appendix.
4.2.4.2 Heat Pump Operates at an Intermediate Compressor Speed (k = i)
or, for a Variable-Speed Non-Communicating Coil-Only Heat Pump, Cycles
Between High and Low Speeds, in Order to Match the Building Heating
Load at a Temperature Tj, Qh\k=1\(Tj)
< QBL(Tj) < Qh\k=2\(Tj).
For units that are not variable-speed non-communicating coil-
only heat pumps, calculate:
[GRAPHIC] [TIFF OMITTED] TR25OC22.090
Where:
[GRAPHIC] [TIFF OMITTED] TR25OC22.091
And [delta](Tj) is evaluated using Equation 4.2.3-3,
while:
Qh\k=i\(Tj) = BL(Tj), the space
heating capacity delivered by the unit in matching the building load
at temperature (Tj), in Btu/h. The matching occurs with
the heat pump operating at compressor speed k=i, and
COP\k=i\(Tj) = the steady-state coefficient of
performance of the heat pump when operating at compressor speed k=i
and temperature Tj (dimensionless). For each temperature
bin where the heat pump operates at an intermediate compressor
speed, determine COP\k=i\(Tj) using the following
equations,
For each temperature bin where Qh\k=1\(Tj)
< BL(Tj) < Qh\k=v\(Tj),
[[Page 64607]]
[GRAPHIC] [TIFF OMITTED] TR25OC22.092
For each temperature bin where Qh\k=v\(Tj)
<= BL(Tj) < Qh\k=2\(Tj),
[GRAPHIC] [TIFF OMITTED] TR25OC22.093
Where:
COPh\k=1\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at minimum compressor
speed and temperature Tj, dimensionless, calculated using capacity
Qh\k=1\(Tj) calculated using Equation 4.2.4-1
or 4.2.4-3 to this appendix and electrical power consumption
[Edot]h\k=1\(Tj) calculated using Equation
4.2.4-2 or 4.2.4-4 to this appendix;
COPh\k=v\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at intermediate
compressor speed and temperature Tj, dimensionless, calculated using
capacity Qh\k=v\(Tj) calculated using Equation
4.2.4-7 to this appendix and electrical power consumption
[Edot]h\k=v\(Tj) calculated using Equation
4.2.4-8 to this appendix;
COPh\k=2\(Tj) is the steady-state coefficient
of performance of the heat pump when operating at full compressor
speed and temperature Tj (dimensionless), calculated using capacity
Qh\k=2\(Tj) and electrical power consumption
[Edot]h\k=2\(Tj), both calculated as described
in section 4.2.4 of this appendix; and
BL(Tj) is the building heating load at temperature
Tj, in Btu/h.
[GRAPHIC] [TIFF OMITTED] TR25OC22.094
* * * * *
[FR Doc. 2022-22257 Filed 10-24-22; 8:45 am]
BILLING CODE 6450-01-P