[Federal Register Volume 87, Number 140 (Friday, July 22, 2022)]
[Notices]
[Pages 43808-43837]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-15726]


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DEPARTMENT OF ENERGY

[Case Number 2022-004; EERE-2022-BT-WAV-0010]


Energy Conservation Program: Notification of Petition for Waiver 
of Norlake, Inc., dba Refrigerated Solutions Group, From the Department 
of Energy Walk-In Coolers and Walk-In Freezers Test Procedure and 
Notification of Grant of Interim Waiver

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

ACTION: Notification of petition for waiver and grant of an interim 
waiver; request for comments.

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SUMMARY: This notification announces receipt of and publishes a 
petition for waiver and interim waiver from Norlake, Inc., dba 
Refrigerated Solutions Group (``RSG''), which seeks a waiver for 
specified walk-in cooler and walk-in freezer (``walk-in'') 
refrigeration system basic models from the U.S. Department of Energy 
(``DOE'') test procedure used for determining the efficiency of walk-in 
refrigeration systems. DOE also gives notification of an Interim Waiver 
Order that requires RSG to test and rate the specified walk-in basic 
models in accordance with the alternate test procedure set forth in the 
Interim Waiver Order. DOE solicits comments, data, and information 
concerning RSG's petition and its suggested alternate test procedure so 
as to inform DOE's final decision on RSG's waiver request.

DATES: Written comments and information are requested and will be 
accepted on or before August 22, 2022.

ADDRESSES: Interested persons are encouraged to submit comments using 
the Federal eRulemaking Portal at www.regulations.gov under docket 
number EERE-2022-BT-WAV-0010. Alternatively, interested persons may 
submit comments, identified by docket number EERE-2022-BT-WAV-0010, by 
any of the following methods:
    1. Email: to [email protected]. Include docket number 
EERE-2022-BT-WAV-0010 in the subject line of the message.
    2. Postal Mail: Appliance and Equipment Standards Program, U.S. 
Department of Energy, Building Technologies Office, Mailstop EE-5B, 
1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone: 
(202) 287-1445. If possible, please submit all items on a compact disc 
(``CD''), in which case it is not necessary to include printed copies.
    3. Hand Delivery/Courier: Appliance and Equipment Standards 
Program, U.S.

[[Page 43809]]

Department of Energy, Building Technologies Office, 950 L'Enfant Plaza 
SW, 6th Floor, Washington, DC 20024. Telephone: (202) 287-1445. If 
possible, please submit all items on a CD, in which case it is not 
necessary to include printed copies.
    No telefacsimiles (``faxes'') will be accepted. For detailed 
instructions on submitting comments and additional information on this 
process, see the SUPPLEMENTARY INFORMATION section of this document.
    Docket: The docket, which includes Federal Register notices, 
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, some documents listed in the 
index, such as those containing information that is exempt from public 
disclosure, may not be publicly available.
    The docket web page can be found at www.regulations.gov/document/EERE-2022-BT-WAV-0010-0001. The docket web page contains instruction on 
how to access all documents, including public comments, in the docket. 
See the SUPPLEMENTARY INFORMATION section for information on how to 
submit comments through www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: 
    Ms. Julia Hegarty, U.S. Department of Energy, Office of Energy 
Efficiency and Renewable Energy, Building Technologies Office, Mailstop 
EE-5B, 1000 Independence Avenue SW, Washington, DC 20585-0121. 
Telephone: (240) 597-6737. Email: [email protected].
    Mr. Michael Kido, U.S. Department of Energy, Office of the General 
Counsel, Mail Stop GC-33, Forrestal Building, 1000 Independence Avenue 
SW, Washington, DC 20585-0103. Telephone: (202) 586-8145. Email: 
[email protected].

SUPPLEMENTARY INFORMATION: DOE is publishing RSG's petition for waiver 
in its entirety, pursuant to 10 CFR 431.401(b)(1)(iv).\1\ DOE is also 
publishing the Interim Waiver Order granted RSG, which serves as 
notification of DOE's determination regarding RSG's petition for an 
interim waiver, pursuant to 10 CFR 431.401(e)(3). DOE invites all 
interested parties to submit in writing by August 22, 2022, comments 
and information on all aspects of the petition, including the alternate 
test procedure. Pursuant to 10 CFR 431.401(d), any person submitting 
written comments to DOE must also send a copy of such comments to the 
petitioner. The contact information for the petitioner is Mr. Bill 
Larson, [email protected].
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    \1\ The petition did not identify any of the information 
contained therein as confidential business information.
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    Submitting comments via www.regulations.gov. The 
www.regulations.gov web page will require you to provide your name and 
contact information. Your contact information will be viewable to DOE 
Building Technologies staff only. Your contact information will not be 
publicly viewable except for your first and last names, organization 
name (if any), and submitter representative name (if any). If your 
comment is not processed properly because of technical difficulties, 
DOE will use this information to contact you. If DOE cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, DOE may not be able to consider your comment.
    However, your contact information will be publicly viewable if you 
include it in the comment or in any documents attached to your comment. 
Any information that you do not want to be publicly viewable should not 
be included in your comment, nor in any document attached to your 
comment. If this instruction is followed, persons viewing comments will 
see only first and last names, organization names, correspondence 
containing comments, and any documents submitted with the comments.
    Do not submit to www.regulations.gov information for which 
disclosure is restricted by statute, such as trade secrets and 
commercial or financial information (hereinafter referred to as 
Confidential Business Information (``CBI'')). Comments submitted 
through www.regulations.gov cannot be claimed as CBI. Comments received 
through the website will waive any CBI claims for the information 
submitted. For information on submitting CBI, see the Confidential 
Business Information section.
    DOE processes submissions made through www.regulations.gov before 
posting. Normally, comments will be posted within a few days of being 
submitted. However, if large volumes of comments are being processed 
simultaneously, your comment may not be viewable for up to several 
weeks. Please keep the comment tracking number that www.regulations.gov 
provides after you have successfully uploaded your comment.
    Submitting comments via email, hand delivery/courier, or postal 
mail. Comments and documents submitted via email, hand delivery/
courier, or postal mail also will be posted to www.regulations.gov. If 
you do not want your personal contact information to be publicly 
viewable, do not include it in your comment or any accompanying 
documents. Instead, provide your contact information on a cover letter. 
Include your first and last names, email address, telephone number, and 
optional mailing address. The cover letter will not be publicly 
viewable as long as it does not include any comments.
    Include contact information each time you submit comments, data, 
documents, and other information to DOE. If you submit via postal mail 
or hand delivery/courier, please provide all items on a CD, if 
feasible, in which case it is not necessary to submit printed copies. 
Faxes will not be accepted.
    Comments, data, and other information submitted to DOE 
electronically should be provided in PDF (preferred), Microsoft Word or 
Excel, WordPerfect, or text (ASCII) file format. Provide documents that 
are not secured, written in English and free of any defects or viruses. 
Documents should not contain special characters or any form of 
encryption and, if possible, they should carry the electronic signature 
of the author.
    Campaign form letters. Please submit campaign form letters by the 
originating organization in batches of between 50 to 500 form letters 
per PDF or as one form letter with a list of supporters' names compiled 
into one or more PDFs. This reduces comment processing and posting 
time.
    Confidential Business Information. According to 10 CFR 1004.11, any 
person submitting information that he or she believes to be 
confidential and exempt by law from public disclosure should submit via 
email two well-marked copies: one copy of the document marked 
confidential including all the information believed to be confidential, 
and one copy of the document marked ``non-confidential'' with the 
information believed to be confidential deleted. Submit these documents 
via email. DOE will make its own determination about the confidential 
status of the information and treat it according to its determination.
    It is DOE's policy that all comments may be included in the public 
docket, without change and as received, including any personal 
information provided in the comments (except information deemed to be 
exempt from public disclosure).

[[Page 43810]]

Case Number 2022-004

Interim Waiver Order

I. Background and Authority

    The Energy Policy and Conservation Act, as amended (``EPCA''),\2\ 
authorizes the U.S. Department of Energy (``DOE'') to regulate the 
energy efficiency of a number of consumer products and certain 
industrial equipment. (42 U.S.C. 6291-6317) Title III, Part C \3\ of 
EPCA established the Energy Conservation Program for Certain Industrial 
Equipment, which sets forth a variety of provisions designed to improve 
energy efficiency for certain types of industrial equipment. This 
equipment includes walk-in coolers and walk-in freezers (``walk-ins''), 
the focus of this document. (42 U.S.C. 6311(1)(G))
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    \2\ All references to EPCA in this document refer to the statute 
as amended through the Energy Act of 2020, Public Law 116-260 (Dec. 
27, 2020), which reflect the last statutory amendments that impact 
Parts A and A-1 of EPCA.
    \3\ For editorial reasons, upon codification in the U.S. Code, 
Part C was redesignated as Part A-1.
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    The energy conservation program under EPCA consists essentially of 
four parts: (1) testing, (2) labeling, (3) Federal energy conservation 
standards, and (4) certification and enforcement procedures. Relevant 
provisions of EPCA include definitions (42 U.S.C. 6311), energy 
conservation standards (42 U.S.C. 6313), test procedures (42 U.S.C. 
6314), labeling provisions (42 U.S.C. 6315), and the authority to 
require information and reports from manufacturers (42 U.S.C. 6316).
    The Federal testing requirements consist of test procedures that 
manufacturers of covered equipment must use as the basis for: (1) 
certifying to DOE that their equipment complies with the applicable 
energy conservation standards adopted pursuant to EPCA (42 U.S.C. 
6316(a); 42 U.S.C. 6295(s)), and (2) making representations about the 
efficiency of that equipment (42 U.S.C. 6314(d)). Similarly, DOE must 
use these test procedures to determine whether the equipment complies 
with relevant standards promulgated under EPCA. (42 U.S.C. 6316(a); 42 
U.S.C. 6295(s))
    Under 42 U.S.C. 6314, EPCA sets forth the criteria and procedures 
DOE is required to follow when prescribing or amending test procedures 
for covered equipment. EPCA requires that any test procedures 
prescribed or amended under this section must be reasonably designed to 
produce test results which reflect the energy efficiency, energy use or 
estimated annual operating cost of covered equipment during a 
representative average use cycle and requires that test procedures not 
be unduly burdensome to conduct. (42 U.S.C. 6314(a)(2)) The test 
procedure used to determine the net capacity and annual walk-in energy 
factor (``AWEF'') of walk-in refrigeration systems is contained in the 
Code of Federal Regulations (``CFR'') at 10 CFR part 431, subpart R, 
appendix C, Uniform Test Method for the Measurement of Net Capacity and 
AWEF of Walk-in Cooler and Walk-in Freezer Refrigeration Systems'' 
(``appendix C to subpart R'').
    Under 10 CFR 431.401, any interested person may submit a petition 
for waiver from DOE's test procedure requirements. DOE will grant a 
waiver from the test procedure requirements if DOE determines either 
that the basic model(s) for which the waiver was requested contains a 
design characteristic that prevents testing of the basic model 
according to the prescribed test procedures, or that the prescribed 
test procedures evaluate the basic model in a manner so 
unrepresentative of its true energy or water consumption 
characteristics as to provide materially inaccurate comparative data. 
10 CFR 431.401(f)(2). A petitioner must include in its petition any 
alternate test procedures known to the petitioner to evaluate the 
performance of the equipment type in a manner representative of the 
energy and/or water consumption characteristics of the basic model. 10 
CFR 431.401(b)(1)(iii). DOE may grant the waiver subject to conditions, 
including adherence to alternate test procedures. 10 CFR 431.401(f)(2).
    As soon as practicable after the granting of any waiver, DOE will 
publish in the Federal Register a notice of proposed rulemaking to 
amend its regulations so as to eliminate any need for the continuation 
of such waiver. 10 CFR 431.401(l) As soon thereafter as practicable, 
DOE will publish in the Federal Register a final rule to that effect. 
Id.
    The waiver process also provides that DOE may grant an interim 
waiver if it appears likely that the underlying petition for waiver 
will be granted and/or if DOE determines that it would be desirable for 
public policy reasons to grant immediate relief pending a determination 
on the petition for waiver. 10 CFR 431.401(e)(3). Within one year of 
issuance of an interim waiver, DOE will either: (i) publish in the 
Federal Register a determination on the petition for waiver; or (ii) 
publish in the Federal Register a new or amended test procedure that 
addresses the issues presented in the waiver. 10 CFR 431.401(h)(1).
    If the interim waiver test procedure methodology is different than 
the decision and order test procedure methodology, certification 
reports to DOE required under 10 CFR 429.12 and any representations 
must be based on either of the two methodologies until 180-360 days 
after the publication date of the decision and order, as specified by 
DOE in the decision and order. Thereafter, certification reports and 
any representations must be based on the decision and order test 
procedure methodology, unless otherwise specified by DOE. 10 CFR 
431.401(i). When DOE amends the test procedure to address the issues 
presented in a waiver, the waiver will automatically terminate on the 
date on which use of that test procedure is required to demonstrate 
compliance. 10 CFR 431.401(h)(2).

II. RSG's Petition for Waiver and Interim Waiver

    On February 17, 2022, DOE received from RSG a petition for waiver 
and interim waiver from the test procedure for walk-in refrigeration 
systems set forth at 10 CFR part 431 subpart R appendix C. (RSG, No. 1, 
attachment 1, at pp. 1-3 \4\) Pursuant to 10 CFR 431.401(e)(i), DOE 
posted the petition on the DOE website. The petition did not identify 
any of the information contained therein as confidential business 
information.
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    \4\ A notation in this form provides a reference for information 
that is in the docket for this test procedure waiver (Docket No. 
EERE-2022-BT-WAV-0010-0001) (available at www.regulations.gov/document/EERE-2022-BT-WAV-0010-0001). This notation indicates that 
the statement preceding the reference is from document number 1 in 
the docket and appears at pages 1-3 of attachment 1 of that 
document. There are two attachments to document 1 of this docket. 
Attachment 1 is titled ``DOE Waiver 021722.'' Attachment 2 is titled 
``RSG DOE Single Package System Alternate Test Procedure 021522''.
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    DOE's current test procedure for walk-in refrigeration systems is 
codified in appendix C to subpart R of part 431 and incorporates by 
reference Air-Conditioning, Heating, and Refrigeration Institute 
(``AHRI'') Standard 1250-2009 (2009 Standard for Performance Rating of 
Walk-In Coolers and Freezers, ``AHRI 1250-2009''), AHRI Standard 420-
2008 (Performance Rating of Forced-Circulation Free-Delivery Unit 
Coolers for Refrigeration, ``AHRI 420-2008''), and American Society of 
Heating, Refrigerating, and Air-Conditioning Engineers (``ASHRAE'') 
Standard 23.1-2010 (Methods of Testing for Rating the Performance of 
Positive Displacement Refrigerant Compressors and Condensing Units that 
Operate at Subcritical Temperatures of the Refrigerant, ``ASHRAE 23.1-
2010''). AHRI 1250-2009 is the industry test standard for refrigeration 
systems for

[[Page 43811]]

walk-in coolers and freezers, including unit coolers and dedicated 
condensing units sold separately, as well as matched pairs. The 
procedure describes the method for measuring the refrigeration capacity 
and the electrical energy consumption for walk-in refrigeration 
systems. Using the refrigeration capacity and electrical energy 
consumption, AHRI 1250-2009 provides a calculation methodology to 
compute AWEF, the applicable energy-performance metric for 
refrigeration systems.
    In its petition for waiver and interim waiver, RSG presents several 
ways in which the currently prescribed test procedure would evaluate 
the specified basic models in a manner so unrepresentative of their 
true energy consumption as to provide materially inaccurate comparative 
data. These issues are summarized below.
    First, as presented in RSG's petition, the specified basic models 
of walk-in refrigeration systems are single-packaged dedicated systems 
that contain multiple refrigeration circuits that operate using a 
single power feed. (RSG, No. 1, attachment 1, at p. 1) RSG claimed that 
the specified basic models meet the definition of a single-packaged 
dedicated system. Id. DOE defines a single-packaged dedicated system as 
``a single-package assembly that includes one or more compressors, a 
condenser, a means for forced circulation of refrigerated air, and 
elements by which heat is transferred from air to refrigerant, without 
any element external to the system imposing resistance to flow of the 
refrigerated air''. See 10 CFR 431.302. As described by RSG, each 
refrigeration circuit in the specified basic models is made up of a 
compressor, expansion device, condenser, and evaporator. (RSG, No. 1, 
attachment 1, at p. 1) The separate refrigeration circuits may share 
condenser fans, evaporator fans and a control system. Id. In its 
request for waiver and interim waiver, RSG stated that neither appendix 
C to subpart R nor AHRI 1250-2009 provide a method for testing a 
single-packaged dedicated system with multiple refrigeration circuits. 
Id.
    Second, RSG stated that the current test procedure requires that 
the unit under test be set up using a 25-foot line set. Id. Section 3.3 
of appendix C to subpart R provides the test method for matched 
systems, single-packaged dedicated systems, and unit coolers tested 
alone, which references AHRI 1250-2009. Section C5 (Methods of Testing 
for Walk-In Cooler and Freezer Systems that Have Matched Unit Coolers 
and Condensing Units) of AHRI 1250-2009 references test setup 
requirements that include the addition of a line set that includes 
either one or two mass flow meters. Under Section C5 of AHRI 1250-2009, 
the gross refrigeration capacity must be determined either by the dual 
instrumentation refrigerant enthalpy method (Section C5.1.1 of AHRI 
1250-2009, Method 1) or by the calibrated box method (Section C5.1.2 of 
AHRI 1250-2009, Method 2). Both methods require installation of a 
refrigerant mass flow meter in the system's liquid line to determine 
the cooling capacity. Section C8.3 and Figure C1 of AHRI 1250-2009 
specify the setup and measurements to be conducted for Method 1, for 
which 25-feet of additional refrigerant line is added to connect the 
condenser to the evaporator (unit cooler). Within this 25-foot line, 
two mass flow meters are incorporated, and the heat balance calculated 
from the two flow measurements must be within 5 percent. 
Section C9.2 and Figure C2 of AHRI 1250-2009 specify the setup and 
measurements for Method 2, in which 26-feet of additional refrigerant 
line is added to connect the condenser to the unit cooler (as for 
Method 1), incorporating one mass flow meter. Air-side gross 
refrigeration capacity and refrigerant-side gross refrigeration 
capacity are determined and must be equal to within 5 
percent for the test to be considered valid. The 25-foot and 26-foot 
\5\ of additional liquid line and suction line piping used to set up 
the test is termed a ``line-set''. In its petition for wavier and 
interim waiver, RSG stated that single-packaged dedicated systems are 
not intended to be remotely split via a line-set. (RSG, No. 1, 
attachment 1, at p. 1)
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    \5\ There is no explanation in AHRI 1250-2009 about why Method 1 
requires 25 feet of refrigeration line and Method 2 requires 26 feet 
of refrigeration line during test set up.
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    In its request for wavier and interim wavier, RSG noted that DOE 
has issued test procedure waivers for single-packaged dedicated 
refrigeration systems using air enthalpy test methods. (RSG, No. 1, 
attachment 1, at p. 2) DOE granted a waiver to Store It Cold for 
single-packaged units on August 9, 2019. 84 FR 39286. Store It Cold 
petitioned for a waiver after determining that the dual instrumentation 
refrigerant enthalpy method specified in AHRI 1250-2009 was not 
providing consistent capacity measurements for its single-packaged 
dedicated systems. 84 FR 39286, 39287. The alternate test procedure 
associated with this prior waiver required that the specified single-
packaged basic models shall be tested using the Indoor Air Enthalpy 
Method and the Outdoor Air Enthalpy Method in accordance with ASHRAE 37 
(Methods of Testing for Rating Electrically Driven Unitary Air-
Conditioning and Heat-Pump Equipment, ``ASHRAE 37''). 84 FR 39286, 
39292. DOE also granted waivers to Air Innovations, CellarPro, 
Vinotemp, and Vinotheque for walk-in refrigeration systems used in wine 
cellar applications, for which some of the basic models included in 
these waivers were single-packaged dedicated systems.\6\ The alternate 
test methods included in these waivers require the specified basic 
models to be tested in accordance with AHRI 1250-2020, which references 
the air enthalpy methods in ASHRAE 37 for testing single-packaged 
dedicated systems.\7\ Use of air enthalpy methods for testing a single-
packaged dedicated system capture the impact of thermal loss and the 
infiltration of warm air into the evaporator portion of these systems, 
which increases the refrigerant load on the system. In its petition for 
waiver and interim waiver, RSG stated that its laboratory is not set up 
to conduct air enthalpy testing, and that it would require substantial 
time and expense to set up its laboratory to conduct air enthalpy 
testing. (RSG, No. 1, attachment 1, at p. 2) Additionally, RSG 
explained that it contacted third-party labs to inquire about testing 
single-packaged dedicated systems using the air enthalpy method, but 
these labs responded that they are not currently able to conduct air 
enthalpy testing. Id.
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    \6\ See Waiver Decision and Orders for Air Innovations (86 FR 
23702 (May 4, 2021)), CellarPro (86 FR 26496 (May 14, 2021)), 
Vinotheque (86 FR 26504 (May 14, 2021)), and Vinotemp (86 FR 36732 
(July 13, 2021)).
    \7\ Subsequent to DOE's grant of waiver to Store It Cold, AHRI 
published an updated version of AHRI 1250 (i.e., AHRI 1250-2020) 
that provides testing provisions for single-packaged dedicated 
systems that incorporate by reference the approach used in ASHRAE 37 
with some modification.
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    Third, in its request for waiver and interim waiver from the DOE 
test procedure, RSG stated that the current tolerance requirement of 
0.5 [deg]F for the on-coil temperature in Section C3.3.3 of AHRI 1250-
2009 is unrealistic. Id. RSG stated that indoor air temperature 
tolerances impact the on-coil temperatures and that the test procedure 
currently prescribes a 1 [deg]F indoor air temperature test condition 
tolerance.\8\ Id. RSG therefore suggested that the on-coil temperature 
tolerance should also be

[[Page 43812]]

1 [deg]F. Id. RSG noted further that it can be difficult to repeatedly 
achieve an on-coil temperature tolerance of 0.5 [deg]F when units are 
shut down, re-plumbed, and recharged for testing. Id.
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    \8\ Test condition tolerance is the maximum allowed deviation of 
the average of the measurements of a parameter made during a test 
period as compared with its target value. The indoor air dry-bulb 
test condition tolerance is specified as 1 [deg]F in Table 2 of AHRI 
1250-2009.
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    RSG also requested an interim waiver from the existing DOE test 
procedure, explaining that if DOE were to deny its application for 
waiver and interim waiver, it would experience economic hardship in the 
form of lost sales and/or a significant delay in the distribution into 
commerce of the specified basic models. Id. DOE will grant an interim 
waiver if it appears likely that the petition for waiver will be 
granted, and/or if DOE determines that it would be desirable for public 
policy reasons to grant immediate relief pending a determination of the 
petition for waiver. 10 CFR 431.401(e)(3).

III. Requested Alternate Test Procedure

    EPCA requires that manufacturers use DOE test procedures when 
making representations about the energy consumption and energy 
consumption costs of covered equipment. (42 U.S.C. 6314(d)) Consistency 
is important when making representations about the energy efficiency of 
covered equipment, including when demonstrating compliance with 
applicable DOE energy conservation standards. Pursuant to 10 CFR 
431.401, and after consideration of public comments on the petition, 
DOE may establish in a subsequent Decision and Order an alternate test 
procedure for the basic models addressed by the Interim Waiver Order.
    RSG seeks to use an alternate test procedure to test and rate 
specific walk-in single-packaged dedicated refrigeration system basic 
models. The alternate test procedure presented by RSG suggested the 
following revisions to the DOE test procedure that would:
    (1) Modify test operating and test condition tolerances in AHRI 
1250-2009, which the DOE test procedure references in section 3.1, 
General modifications: Test Conditions and Tolerances;
    (2) Remove section 3.2.5 from the DOE test procedure, which 
provides additional specificity to the refrigerant line setup required 
in AHRI 1250-2009 section C8.3; and
    (3) Create a new section 4 in the DOE test procedure that provides 
modifications to AHRI 1250-2009 and includes a new approach for testing 
multiple-circuit single-packaged dedicated systems. Specifically, RSG 
has suggested an alternate test procedure for testing single-packaged 
dedicated systems using a modified refrigerant enthalpy approach 
applied to multiple refrigeration circuits. (RSG, No. 1, attachment 2, 
at pp. 1-13).
    In its request for waiver and interim waiver, RSG suggested testing 
single-packaged dedicated systems using either a modification of the 
calibrated box method described in Section C9 of AHRI 1250-2009 or the 
indoor air enthalpy method (as described in Section C9.1.1 of AHRI 
1250-2020) as the primary test method and a new ``single-package 
refrigerant enthalpy method'' as the secondary test method. (RSG, No. 
1, attachment 2, at p. 3) Specifically, RSG recommended the following 
approach for the new single-package refrigerant enthalpy method:
    (1) Instead of using a 25-foot line set with two mass flow meters 
as specified in the dual instrumentation refrigerant enthalpy method 
(see Section C8 of AHRI 1250-2009), RSG suggested using only one mass 
flow meter in the liquid line between the heat exchanger and the 
expansion device. (RSG, No. 1, attachment 1, at p. 1)
    (2) In its alternate test procedure, RSG suggested incorporating 
the mass flow meter with less than or equal to 5 feet of additional 
insulated refrigerant line (with piping matching that of the system 
under test) to the liquid line. Id.
    (3) The existing suction line would be undisturbed for the test. 
Id.
    (4) The added refrigerant charge for the 5 feet of additional 
liquid line and the mass flow meter would be determined using Section 
C3.3.3 of AHRI 1250-2009 of the current test procedure. Id.
    Before disassembling the refrigeration system to set up the 
refrigerant-side mass flow measurement, a preliminary test at Condition 
A would be conducted using only a modified calibrated box method or the 
indoor air enthalpy method. (RSG, No. 1, attachment 1, at p. 3) For 
this test, surface-mounted temperature sensors would be installed on 
the evaporator and condenser coils, tubing entering and leaving the 
compressor, and tubing entering the expansion device. Id. To limit the 
alteration of the refrigerant circuit, the new suggested single-
packaged refrigeration enthalpy method would add only 5 feet of tubing 
to the liquid refrigerant lines (not including the flow length 
associated with the mass flow meter). (RSG, No. 1, attachment 2, at p. 
4) To ensure that the refrigerant circuit modifications (i.e., addition 
of the mass flow meter and additional liquid line) do not materially 
alter the system operation, a secondary test would be performed after 
adding the mass flow meter to confirm that (1) each on-coil temperature 
sensor indicates a reading that is within 1 [deg]F of its 
initial test measurement, (2) the temperatures of the refrigerant 
entering and leaving the compressor are within 4 [deg]F of 
the initial test measurement, and (3) the refrigerant temperature 
entering the expansion device is within 1 [deg]F of the 
initial test measurement. Both the preliminary Condition A test and the 
secondary test would be additions to the current test procedure and 
provide a check that the modifications to the refrigeration circuit do 
not significantly impact the operation of the unit.
    The heat balance applied to single-packaged dedicated systems using 
this method would involve comparison of the air-side net capacity to a 
net capacity determined based on the refrigerant enthalpy method 
capacity measurement that would include adjustment for the evaporator 
fan heat in addition to adjustment for the single-packaged dedicated 
system thermal loss. The thermal loss would be calculated similarly to 
the duct loss calculation of Section 7.3.3.3 of ASHRAE 37-2009, in 
which the heat losses associated with the insulated surface areas 
subject to heat transfer are summed based on their surface area, 
thermal resistance (which is based on known insulating material and 
insulation thickness), and the temperatures on either side of the 
surface. A test is considered valid if the refrigerant capacities 
determined by each method are within 6 percent of each other. This 
approach is generally consistent to the current DOE test procedure, 
which requires that the capacities determined from two tests are within 
5 percent in order for the test to be considered valid.
    RSG's suggestion to use the calibrated box method with a single-
packaged dedicated system involves mounting the system on the 
calibrated box, similar to its installation on a walk-in for field use 
and exchanging air with the box interior to cool it. The exterior of 
the calibrated box would be conditioned such that the air conditions 
entering the single-packaged dedicated system's condenser match the 
targets specified in RSG's suggested revisions to Tables 3, 4, 7 and 8 
of AHRI 1250-2009. DOE notes that the table revisions suggested by RSG 
are consistent with previous single-packaged dedicated system waivers 
(see, e.g., the Store It Cold waiver, 84 FR 39286, 39291 (August 9, 
2019)). The warm condensing unit portion of the single-packaged 
dedicated system and its condenser discharge air may in some cases add 
to the thermal load imposed on the calibrated box. Therefore, RSG has 
suggested additional optional test methods to quantify this additional 
thermal load on the calibrated box, and to adjust for it when 
determining system

[[Page 43813]]

capacity. The suggested additional test method to determine the 
additional thermal load calls for box calibration and box load 
determination to be based on temperature sensors mounted on the box 
exterior surface rather than by measuring air temperature just outside 
the box (the approach described for the calibrated box method in 
Section C9 of AHRI 1250-2009). In addition, requirements for 
temperature sensor placement to measure the surfaces that may be hot 
during system operation, and equations for adjustment of the calculated 
box transmission load contributing to the capacity determination were 
provided by RSG. (RSG, No. 1, attachment 2, at p. 11)
    In its request for waiver and interim waiver, RSG also provided 
instructions for extending the modified refrigerant enthalpy method of 
the alternate test procedure to testing multiple-circuit single-
packaged dedicated systems. (RSG, No. 1, attachment 2, at p. 9) The 
approach involves measuring refrigerant mass flow and the enthalpy 
entering and leaving the evaporator for each refrigeration circuit 
contained in the unit. The measured mass flow and enthalpy values are 
used to calculate the gross refrigeration capacity for each circuit. 
Each circuit's gross capacity is then summed to determine the total 
gross capacity of the system, which would be adjusted to determine net 
capacity as described above for testing a single-circuit system.

IV. Interim Waiver Order

    DOE has reviewed RSG's application for waiver and interim waiver 
and the alternate test procedure requested by RSG. Based on the 
assertions in the petition, the DOE test procedure for walk-in cooler 
refrigeration systems would evaluate the subject basic models in a 
manner so unrepresentative of its true energy consumption 
characteristics as to provide materially inaccurate comparative data.
    DOE notes that its current test procedure for walk-in refrigeration 
systems specifies, through reference to appendix C of AHRI 1250-2009, 
determining the capacity of the unit under test by using either the 
dual instrumentation refrigerant enthalpy method (i.e., Method 1 in 
Section C8 of AHRI 1250-2009) or the calibrated box method (i.e., 
Method 2 in Section C9 of AHRI 1250-2009). Two capacity measurements 
are obtained from either Method 1 or Method 2 and the determined 
capacities must be within 5 percent of each other for a 
valid test (see AHRI 1250-2009, Section C8.5.3 for Method 1 and Section 
C9.4.5 for Method 2). The dual instrumentation refrigerant enthalpy 
method is routinely used to evaluate the capacity of matched pair, 
dedicated condensing, and unit cooler systems, but DOE understands that 
this method is generally considered to be impractical for testing 
single-packaged dedicated systems. This is primarily because it 
requires breaking into the liquid refrigerant line within the packaged 
unit, routing the line outside of the unit to pass through two mass 
flow meters, and then routing the line back into the unit and through 
dual pressure and temperature measurements before it rejoins the 
original liquid line at the expansion device inlet. This method is 
generally inappropriate for single-packaged dedicated systems because 
the internal volume of the added liquid line and mass flow meters adds 
substantially to the required refrigerant charge, and the entire 
assembly adds substantial pressure drop.\9\
---------------------------------------------------------------------------

    \9\ These issues were the primary motivation for and are 
described in the Store It Cold petition for waiver. 84 FR 11944, 
11946.
---------------------------------------------------------------------------

    As discussed, RSG's request for waiver and interim waiver stated 
that the dual instrumentation refrigerant enthalpy method is not 
appropriate for testing single-packaged dedicated systems because these 
systems are not designed to have significant additional refrigerant 
line added between the condenser and evaporator. RSG also stated that 
the single-packaged dedicated system test methods in AHRI 1250-2020 
result in a significant test burden if a testing facility is not 
currently set up for air enthalpy testing. Therefore, in its suggested 
alternate test procedure, RSG presented an approach for testing single-
packaged dedicated systems using the calibrated box method (Method 2 of 
AHRI 1250-2009) with modifications that allow a liquid refrigerant line 
no longer than 5 feet to be incorporated into the existing refrigerant 
line with a mass flow meter. The method suggested by RSG would make no 
changes to the vapor refrigeration line. Based on its review of 
proprietary data from RSG, DOE has initially determined that these 
changes included in the alternate test procedure recommended by RSG 
provide a realistic approach for using refrigerant enthalpy to 
determine the capacity of single-packaged dedicated systems.
    The refrigerant enthalpy method does not account for thermal 
losses, which are specific to single-packaged dedicated systems because 
the evaporator, rather than being installed entirely inside the cold 
walk-in box, is housed in an insulated compartment that is externally 
exposed to warm outdoor air on several sides and to the hot condensing 
unit compartment on another side. To address this, RSG has adjusted the 
capacity determined by the new single-package refrigerant enthalpy 
method to account for thermal losses. Based on its review of RSG's 
suggested alternate test method, DOE has initially determined that 
these capacity adjustments result in representative measures of 
capacity.
    In its petition for waiver, RSG specified that the new single-
package refrigerant method would be considered a secondary method 
(i.e., results would be used to ensure the capacity tolerance is met 
when compared to the capacity determined by a primary test method but 
would not be used for rating performance). DOE has initially determined 
that specifying use of the new single-package refrigerant enthalpy 
method as a secondary method is appropriate since capacity is not 
directly determined by this method (but rather is estimated through the 
application of thermal loss adjustments, as described).
    The primary test method recommended by RSG in its alternate test 
procedure is the calibrated box test. Although the calibrated box test 
is not included in the list of test methods for single-packaged 
dedicated systems in Table C4 of AHRI 1250-2020, DOE notes that the 
calibrated box method and the indoor room calorimeter method (from 
Table C4 of AHRI 1250-2020) are very similar, since the capacity 
measurement is based on the heat input into a room and the calibrated 
thermal transmission is achieved through use of a ``box'' or ``room.'' 
Similarly, the indoor air enthalpy method (from Table C4 of AHRI 1250-
2020) captures the capacity actually delivered to the air that 
conditions the walk-in box. The alternate test methods in the test 
procedure waivers that DOE previously granted for certain single-
packaged dedicated systems rely on the indoor room calorimeter method 
and the indoor air enthalpy method. Given the similarities between 
these methods, DOE expects that the calibrated box method will provide 
capacity measurements that are comparable to those obtained using the 
indoor air enthalpy method or the indoor room calorimeter method. 
Because these methods account for the thermal losses associated with 
single-packaged dedicated systems using direct measurement rather than 
duct loss calculations, DOE has initially determined that it is 
appropriate that the calibrated box method would be considered to be 
the primary test

[[Page 43814]]

method (i.e., the capacity determined from this method would be used 
for rating purposes).
    In its recommended alternate test procedure, RSG recommended a 6 
percent tolerance between the proposed calibrated box and new single-
package refrigerant enthalpy methods. Based on its review of the 
alternate test procedure provided by RSG, DOE has initially determined 
that the alternate test procedure submitted by RSG in its petition for 
waiver and interim waiver provides representative capacity measurements 
that result in representative AWEF values for single-packaged dedicated 
systems.
    DOE's current test procedure does not provide a method for testing 
single-packaged dedicated systems with multiple refrigeration circuits. 
RSG's suggested alternate test procedure would determine the gross 
refrigeration capacity for each circuit using the earlier described 
single-package refrigerant enthalpy method and summing these capacities 
to determine the total system capacity. Based on DOE's review of the 
alternate test procedure provided by RSG, DOE has initially determined 
that this is an appropriate and representative approach for determining 
the performance of multiple-circuit refrigeration systems.
    As previously discussed, RSG's suggested alternate test method 
would modify the test operating and test condition tolerances in 
section 3.1 of the DOE test procedure (which references AHRI 1250-
2009); remove section 3.2.5 from the DOE test procedure, which provides 
additional specificity to the refrigerant line setup required in AHRI 
1250-2009 section C8.3; and create a new section 4 in the DOE test 
procedure that provides a detailed method for testing multiple-circuit 
single-packaged dedicated systems. After review, DOE has initially 
determined that it will specify an alternate test procedure that 
generally follows the same approach as that recommended by RSG for the 
interim waiver test procedure, but with one modification, as described 
follows.
    The alternate test procedure submitted by RSG includes suggested 
revisions to AHRI 1250-2009. However, DOE notes that there is one 
inconsistency between RSG's alternate test procedure and AHRI 1250-
2020. Specifically, the alternate test procedure suggested by RSG 
modifies Table 7 of AHRI 1250-2009 (Fixed Capacity Matched Freezer 
System, Condensing Unit Located Indoors) to require the condenser air 
entering wet-bulb temperature to be 68 [deg]F for single-packaged 
dedicated systems that do not use evaporative dedicated condensing 
units, for which all or part of the equipment is located in the outdoor 
room. (RSG, No. 1, attachment 2, at p. 1) However, Table 8 of AHRI 
1250-2020 requires that the condenser air entering wet-bulb temperature 
must be 65 [deg]F for single-packaged dedicated systems that do not use 
evaporative dedicated condensing units, for which all or part of the 
equipment is located in the outdoor room. DOE has modified the 
condensing air entering wet-bulb temperature in Table 7 of RSG's 
recommended alternate test procedure to be 65 [deg]F (rather than 68 
[deg]F as suggested by RSG) in order to maintain consistency with the 
requirements in Table 8 of AHRI 1250-2020.
    DOE has initially determined that the alternate test procedure (as 
modified in the manner noted), appears to allow for the accurate 
measurement of the energy efficiency of the specified basic models, 
while alleviating the testing problems cited by RSG in its attempts to 
implement the DOE test procedure for these basic models. Consequently, 
DOE has determined that RSG's petition for waiver, with the 
modification as described in this section, likely will be granted. 
Furthermore, DOE has determined that it is desirable for public policy 
reasons to grant RSG immediate relief pending a determination of the 
petition for waiver.
    For the reasons stated, it is ordered that:
    (1) RSG must test and rate the following Norlake and Masterbilt 
basic models with the alternate test procedure set forth in paragraph 
(2).

------------------------------------------------------------------------
       Cooler basic models                 Freezer basic models
------------------------------------------------------------------------
CPB050PC-S-0                      CPF050PC-S-0
CPB075PC-S-0                      CPF075PC-S-0
CPB100PC-S-0                      CPF100PC-S-0
                                  CPF150PC-S-4
                                  CPF200PC-S-4
------------------------------------------------------------------------

    (2) The alternate test procedure for the RSG basic models 
identified in paragraph (1) of this Interim Waiver Order is the test 
procedure for walk-in refrigeration systems prescribed by DOE at 10 CFR 
part 431, subpart R, appendix C (``Appendix C to Subpart R''), except 
that multiple circuit single-packaged dedicated systems shall use: (1) 
either the calibrated box method or an indoor air enthalpy test as the 
primary test method, as detailed below; (2) the modified refrigerant 
enthalpy method as the secondary test method, as detailed below; (3) 
the net capacity from the primary and secondary test methods must agree 
within 6 percent, as detailed below; and (4) reported 
values for the overall system shall be the summation of the gross 
capacities obtained from the modified refrigerant enthalpy method 
conducted for each refrigeration circuit included in the unit under 
test, as detailed below. All other requirements of appendix C to 
subpart R and DOE's regulations remain applicable.
    In Appendix C to Subpart R:
    Revise section 3.1.1 to read as follows:
    3.1.1. In Table 1 of AHRI 1250-2009, Instrumentation Accuracy, 
refrigerant temperature measurements shall have a tolerance of 0.5 [deg]F for unit cooler in/out. Temperature measurements used 
to determine water vapor content of the air shall be accurate to within 
0.4 [deg]F. All other temperature measurements shall be 
accurate to 1.0 [deg]F.
    Revise section 3.1.4 to read as follows:
    3.1.4. In Tables 2 through 14 of AHRI 1250-2009, the Test Condition 
Outdoor Wet Bulb Temperature requirement and its associated tolerance 
apply only to units with evaporative cooling and single-packaged 
dedicated systems.
    Insert new section 3.1.6 as follows:
    3.1.6 Tables 3, 4, 7 and 8 of AHRI 1250-2009 shall be modified to 
read as follows:

                                   Table 3--Fixed Capacity Matched Refrigerator System, Condensing Unit Located Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Unit cooler     Unit cooler
                                      air entering    air entering    Condenser air  Condenser air entering
          Test description              dry-bulb        relative      entering dry-     wet-bulb ([deg]F)       Compressor capacity      Test objective
                                        ([deg]F)      humidity (%)    bulb ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power................              35             <50  ..............  ......................  Compressor Off..........  Measure fan input
                                                                                                                                        wattage during
                                                                                                                                        compressor off
                                                                                                                                        cycle.

[[Page 43815]]

 
Refrigeration Capacity.............              35             <50              90  \1\ 75 or \2\ 65......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, input
                                                                                                                                        power, and EER
                                                                                                                                        at Rating
                                                                                                                                        Condition.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Required only for evaporative Dedicated Condensing Units.
\2\ Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.


                                  Table 4--Fixed Capacity Matched Refrigerator System, Condensing Unit Located Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Unit cooler     Unit cooler
                                      air entering    air entering    Condenser air  Condenser air entering
          Test description              dry-bulb        relative      entering dry-     wet-bulb ([deg]F)       Compressor capacity      Test objective
                                        ([deg]F)      humidity (%)    bulb ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power................              35             <50  ..............  ......................  Compressor Off..........  Measure fan input
                                                                                                                                        wattage during
                                                                                                                                        compressor off
                                                                                                                                        cycle.
Refrigeration Capacity A...........              35             <50              95  \1\ 75 or \2\ 68......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, input
                                                                                                                                        power, and EER
                                                                                                                                        at Rating
                                                                                                                                        Condition.
Refrigeration Capacity B...........              35             <50              59  \1\ 54 or \2\ 46......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, and
                                                                                                                                        system input
                                                                                                                                        power at
                                                                                                                                        moderate
                                                                                                                                        condition.
Refrigeration Capacity C...........              35             <50              35  \1\ 34 or \2\ 29......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, and
                                                                                                                                        system input
                                                                                                                                        power at cold
                                                                                                                                        condition.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Required only for evaporative Dedicated Condensing Units.
\2\ Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.


                                     Table 7--Fixed Capacity Matched Freezer System, Condensing Unit Located Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Unit cooler     Unit cooler
                                      air entering    air entering    Condenser air  Condenser air entering
          Test description              dry-bulb        relative      entering dry-     wet-bulb ([deg]F)       Compressor capacity      Test objective
                                        ([deg]F)      humidity (%)    bulb ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power................             -10             <50  ..............  ......................  Compressor Off..........  Measure fan input
                                                                                                                                        wattage during
                                                                                                                                        compressor off
                                                                                                                                        cycle.
Refrigeration Capacity.............             -10             <50              90  \1\ 75 or \2\ 65......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, input
                                                                                                                                        power, and EER
                                                                                                                                        at Rating
                                                                                                                                        Condition.
Defrost Frost Load.................             -10         Various              90  \1\ 75 or \2\ 65......  System Dependent........  Test according to
                                                                                                                                        Section C11 of
                                                                                                                                        AHRI 1250-2009.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Required only for evaporative Dedicated Condensing Units.
\2\ Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.


                                     Table 8--Fixed Capacity Matched Freezer System, Condensing Unit Located Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                       Unit cooler     Unit cooler
                                      air entering    air entering    Condenser air  Condenser air entering
          Test description              dry-bulb        relative      entering dry-     wet-bulb ([deg]F)       Compressor capacity      Test objective
                                        ([deg]F)      humidity (%)    bulb ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power................             -10             <50  ..............  ......................  Compressor Off..........  Measure fan input
                                                                                                                                        wattage during
                                                                                                                                        compressor off
                                                                                                                                        cycle.
Refrigeration Capacity A...........             -10             <50              95  \1\ 75 or \2\ 68......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, input
                                                                                                                                        power, and EER
                                                                                                                                        at Rating
                                                                                                                                        Condition.
Refrigeration Capacity B...........             -10             <50              59  54\1\ or \2\ 46.......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, input
                                                                                                                                        power, and EER
                                                                                                                                        at Rating
                                                                                                                                        Condition.

[[Page 43816]]

 
Refrigeration Capacity C...........             -10             <50              35  \1\ 34 or \2\ 29......  Compressor On...........  Determine Net
                                                                                                                                        Refrigeration
                                                                                                                                        Capacity of Unit
                                                                                                                                        Cooler, input
                                                                                                                                        power, and EER
                                                                                                                                        at Rating
                                                                                                                                        Condition.
Defrost Frost Load.................             -10         Various              95  \1\ 75 or \2\ 68......  System Dependent........  Test according to
                                                                                                                                        Section C11 of
                                                                                                                                        AHRI 1250-2009.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Required only for evaporative Dedicated Condensing Units.
\2\ Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.

    Remove section 3.2.5.
    Add a new section 4, following section 3.5 Hot Gas Defrost 
Refrigeration Systems

4.0 Multiple-Circuit Single-Packaged Dedicated Systems

    When conducting testing in accordance with AHRI 1250-2009 
(incorporated by reference; see 10 CFR 431.303), the following 
modifications must be made.

4.1 Specific modifications: Test Conditions and Tolerance

    4.1.1 Replace Section C3.1.2 of AHRI 1250-2009 with the following: 
Air wet-bulb and dry-bulb temperatures entering the Single-Packaged 
Dedicated System at its evaporator return and condenser air inlet shall 
be measured based on the airflow area at the point of measurement. One 
measuring station is required for each 2.0 ft2 of the first 
10.0 ft2 of airflow area and one additional measuring 
station is required for each 4.0 ft2 of airflow area above 
10.0 ft2. A minimum of two stations shall be used and the 
number of measuring stations shall be rounded up to the next whole 
number.
    4.1.2 Replace Section C3.1.5 of AHRI 1250-2009 with the following: 
If sampling tubes are used, each tube opening may be considered a 
temperature measuring station provided the openings are uniformly 
spaced along the tube, the airflow rates entering each port are 
relatively uniform (15%) and the arrangement of tubes 
complies with the location requirements of Section C3.1.2 of AHRI 1250-
2009. Additionally, a one-time temperature traverse shall be made over 
the measurement surface, prior to the tests to assess the temperature 
variation and ensure it complies with the allowable deviation specified 
in Section C3.1.4 of AHRI 1250-2009. (Refer to ANSI/ASHRAE Standard 
41.1 for more information and diagrams). If sampling tubes are not used 
for single-packaged dedicated systems that do not use evaporative 
dedicated condensing units, a single air wet-bulb or RH sensor may be 
used. When used, this sensor shall be located at the geometric center 
of the largest condenser coil face and 6-12 inches from the condenser 
coil.
    4.1.3 Replace Section 3.1.6 of AHRI 1250-2009 with the following: 
Refrigerant temperatures entering and leaving the evaporator section of 
the Single-Packaged Dedicated System shall be measured by a temperature 
measuring instrument placed in a thermometer well and inserted into the 
refrigerant stream. These wells shall be filled with non-solidifying, 
thermal conducting liquid or paste to ensure the temperature sensing 
instrument is exposed to a representative temperature. The entering 
temperature of the refrigerant shall be measured within six pipe 
diameters upstream of the expansion device. If the refrigerant tube 
outer diameter is less than \1/2\-inch, the refrigerant temperature may 
be measured using the average of two temperature measuring instruments 
with a minimum accuracy of 0.5 [deg]F placed on opposite 
sides of the refrigerant tube surface. In this case, the refrigerant 
tube shall be insulated with 1-inch-thick insulation from a point 6 
inches upstream of the measurement location to a point 6 inches 
downstream of the measurement location. Also, the entering measurement 
location may be moved to a location 6 inches upstream of the expansion 
device.

4.2 Refrigerant Properties Measurement

    4.2.1 Replace Section C3.3.1 of AHRI 1250-2009 with the following: 
With the equipment operating at the desired test conditions, the 
temperature and pressure of the refrigerant leaving the unit cooler, 
entering the expansion device, and entering and leaving the compressor 
shall be measured. For cases where the calibrated box method or indoor 
air enthalpy method is also conducted, data used to calculate capacity 
according to the single-package refrigerant enthalpy method and the 
additional method shall be collected over the same intervals.
    4.2.2 Replace Section C3.3.3 of AHRI 1250-2009 with the following: 
For Single-Packaged Dedicated Systems tested using either the 
calibrated box method or the indoor air enthalpy method as the primary 
measurement and the single-package refrigerant enthalpy method as the 
secondary method, a preliminary test for Rating Condition A using the 
primary method is required prior to setting up the refrigerant enthalpy 
method measurements. In preparation for this preliminary test, 
temperature sensors shall be attached to the equipment's evaporator and 
condenser coils. The sensors shall be located at points that are not 
affected by vapor superheat or liquid subcooling. Placement near the 
midpoint of the coil, at a return bend, is recommended. The preliminary 
test shall be conducted with the requirement that the temperatures of 
the on-coil sensors be included with the regularly recorded data. After 
the preliminary test is completed, the refrigerant shall be removed 
from the equipment, and the refrigerant enthalpy measurement setup 
shall be completed. The equipment shall be evacuated and recharged with 
refrigerant. The test shall then be repeated. Once steady-state 
operation is achieved, refrigerant shall be added or removed until, as 
compared to the average values from the preliminary test, the following 
conditions are achieved: (1) each on-coil temperature sensor indicates 
a reading that is within 1.0 [deg]F, (2) the temperatures 
of the refrigerant entering and leaving the compressor are within 
4.0 [deg]F, and (3) the refrigerant temperature entering 
the expansion device is within 1.0 [deg]F. Once these 
conditions have been achieved over an interval of at least ten minutes, 
refrigerant charging equipment

[[Page 43817]]

shall be removed, and the remaining tests shall be conducted.
    4.2.3 When conducting the refrigerant enthalpy method for a Single-
Packaged Dedicated System, the length of the added liquid line 
conducting refrigerant out of the system, to the flow meter, and back 
into the system shall be no more than 5 feet. No such modification to 
the suction line shall be made.

4.3 Methods for Testing for Walk-In Cooler and Freezer Systems That 
Have Matched Unit Coolers and Condensing Units

    Disregard Section C5 of AHRI 1250-2009 and instead test according 
to the following method:
    4.3.1 The Refrigeration Capacity for Single-Packaged Dedicated 
Systems shall be determined using either the Calibrated Box method or 
the Indoor Air Enthalpy method as a primary test method and the Single-
Package Refrigerant Enthalpy method as the secondary test method.
    4.3.1.1 Single-Package Refrigerant Enthalpy method shall determine 
gross refrigeration capacity by measuring the enthalpy change and the 
mass flow rate of the refrigerant using a single set of measurements.
    4.3.1.2 Calibrated Box method shall determine net refrigeration 
capacity by measuring the heat input to the calibrated box, including 
thermal transfer through the calibrated box walls.
    4.3.2 Indoor Air Enthalpy method shall determine net refrigeration 
capacity of Single-Packaged Dedicated System and input power in 
accordance with ASHRAE 37-2009, Figure C4 of AHRI 1250-2020, and the 
following modifications.
    4.3.2.1 Net refrigeration capacity is determined by measuring 
airflow rate and the dry-bub temperature and water vapor content of the 
air that enters and leaves the coil.
    4.3.2.2 Air enthalpies shall be determined in accordance with ANSI/
ASHRAE 41.6. Entering air is to be sufficiently dry as to not produce 
frost on the evaporator coil. Therefore, only sensible capacity 
measured by dry bulb change shall be used to calculate capacity.
    4.3.3 Testing Sequence. The primary test method shall be used to 
measure the capacity for Rating Condition A prior to set-up of the 
Single-Package Refrigerant Enthalpy Measurement. After set-up of the 
Refrigerant Enthalpy method, the Net Capacity shall be measured using 
both the primary test method and the Refrigerant Enthalpy method. The 
Net Capacity measurement using the Refrigerant Enthalpy method shall be 
within 6 percent of the net capacity measurement using the primary 
method.
    If a capacity balance within tolerance is not initially achieved, 
take steps to reduce the thermal losses of the Single-Packaged 
Dedicated System evaporator compartment by sealing air gaps and 
potentially adding more external insulation. If using the Calibrated 
Box method as the primary method, achieving a capacity balance may 
require conducting the calibration with calibrated box insulation 
material at the same average temperature as during capacity 
measurement, or using multiple calibrations conducted at different 
average insulation material temperatures and using these data to 
construct a correlation for the calibration coefficient, 
Kcb, as a function of average insulation temperature. The 
official performance measurements are based on the primary method 
testing without any air gap sealing and additional external insulation 
used to achieve the 6 percent energy balance in place.
    4.3.4 The refrigerant enthalpy method Net Capacity shall be 
calculated from the Gross Capacity Measurement as follows.

qss,2 = Qref-3.412 x EFcomp,on-Qsploss

Where Qsploss represents the Single-Packaged Dedicated System 
thermal losses through the walls of the evaporator side of the 
Single-Packaged Dedicated System to the condenser side and to the 
exterior ambient, and shall be calculated as follows.

Qsploss = UAcond x (Tcondside-Tevapside) + UAamb x (Tamb-Tevapside)

Where:

UAcond and UAamb are, for the condenser/evaporator partition and the 
evaporator compartment walls exposed to ambient air, respectively, 
the product of the overall heat transfer coefficient and surface 
area of the unit as manufactured, i.e., without external insulation 
that might have been added during the test;

Tevapside is the air temperature in the evaporator compartment;
Tcondside is the air temperature in the condenser compartment; and
Tamb is the air temperature outside the Single-Packaged Dedicated 
System.

    The Net Capacity to be used in AWEF calculations shall be the net 
capacity measured using the primary method.
    4.3.5 Upon the completion of the Rating Condition A steady state 
test, an off-cycle evaporator fan power test shall be conducted to 
measure the evaporator fan power consumption during a compressor-off 
period in accordance with Section C10 of AHRI 1250-2009.
    4.3.6 Upon the completion of the Rating Condition A steady state 
test for walk-in freezer systems, a mandatory defrost test shall be 
conducted to establish the energy input for a defrost cycle.
    4.3.7 Upon the completion of the Rating Condition A steady state 
test, off-cycle evaporator fan power test, and defrost test (for walk-
in freezer systems), the Rating Condition B and C steady state tests 
shall be conducted. Capacity balance as described in Section C9.2 of 
AHRI 1250-2020 for Rating Condition A is not required for Rating 
Conditions B and C.

4.4 Test Chamber Requirements

    Disregard Section C6 of AHRI 1250-2009 and instead test according 
to the following method:
    4.4.1 For single-packaged dedicated systems, test chamber 
requirements shall be as follows:
    a. For the calibrated box method, follow ASHRAE 16-2016, Section 
6.1 for calibrated type calorimeters excluding water and water energy 
inputs for the indoor-side compartment.
    b. For the indoor air enthalpy method, follow ASHRAE 37-2009.

4.5 Single-Packaged Dedicated System Refrigerant Enthalpy Method

    4.5.1 General Description. In this method, capacity is determined 
from the refrigerant enthalpy change and flow rate. Enthalpy changes 
are determined from measurements of entering and leaving pressures and 
temperatures of the refrigerant, and the flow rate is determined by a 
suitable flow meter in the liquid line. This method shall not be used 
for tests in which the refrigerant liquid leaving the flow meter is 
subcooled less than 3.0 [deg]F or for tests in which any instantaneous 
measurement of the superheat of the vapor leaving the evaporator coil 
is less than 5.0 [deg]F. Supplementary cooling may be artificially 
provided for the liquid line to ensure enough subcooling when making 
measurements to establish the capacity balance for Rating Condition A, 
however, no official measurements used to calculate AWEF may be made 
while providing such supplementary cooling.
    4.5.2 Measurements. Refer to Section 4.1 of this appendix and 
Section C3 of AHRI 1250-2009 for requirements of air-side and 
refrigerant-side measurements.
    4.5.3 Test Setup and Procedure. Refer to Section 4.4 of this 
appendix, Section C7 of AHRI 1250-2009, and Figure C3 of this section 
for specific test setup. The lengths of the added liquid line shall be 
a maximum of 5 feet.
BILLING CODE 6450-01-P

[[Page 43818]]

[GRAPHIC] [TIFF OMITTED] TN22JY22.003

    4.5.4 Data to be Measured and Recorded. Refer to ``Refrigerant 
Enthalpy Method'' in Table C2 in Section C7.2 of AHRI 1250-2009 for the 
required data that need to measured and recorded, except as follows.
    4.5.4.1 Water vapor content of air entering the unit cooler 
(evaporator) and condensing unit may be measured using a wet bulb 
temperature measurement or a relative humidity sensor, but both are not 
required.
    4.5.4.2 Wet bulb temperature of air leaving the unit cooler 
(evaporator) and condensing unit need not be measured.
    4.5.4.3 Required refrigerant pressure measurement includes only 
subcooled liquid entering the expansion valve and superheated vapor 
exiting the unit cooler (evaporator).
    4.5.4.4 Only one refrigerant mass flow measurement is required.
    4.5.4.5 Measurement of Refrigerant oil flow rate and oil/
refrigerant mass ratio are not required.
    4.5.5 Refrigeration Capacity Calculation.
    4.5.5.1 The refrigerant-side gross capacity is calculated by

Qref = mref(hout-hin)

    4.5.5.2 Measurement of Capacity for a Single-Packaged Dedicated 
System with Multiple Refrigeration Circuits.
    For a Single-Packaged Dedicated System with multiple refrigeration 
circuits, apply the refrigerant enthalpy method separately for each 
circuit and sum the separately measured gross refrigeration capacities.

4.6 Calibrated Box Test Procedure

    4.6.1 Measurements. Refer to Section 4.1 of this section and 
Section C3 of AHRI 1250-2009 for requirements of air-side and 
refrigerant-side measurements.

[[Page 43819]]

    4.6.2 Apparatus setup for Calibrated Box Calibration and Test. 
Refer to Section 4.4 of this section, Section C7 of AHRI 1250-2009, and 
Figure C4 of this section for specific test setup.
[GRAPHIC] [TIFF OMITTED] TN22JY22.004

    4.6.2.1 The calibrated box shall be installed in a temperature-
controlled enclosure in which the temperature can be maintained at a 
constant level. When using the calibrated box method for Single-
Packaged Dedicated Systems, the enclosure air temperature shall be 
maintained such that the condenser air entering conditions are as 
specified for the test.
    4.6.2.2 The temperature-controlled enclosure shall be of a size 
that will provide clearances of not less than 18 inches on all sides, 
top and bottom, except that clearance of any one surface may be reduced 
to not less than 5.5 inches.
    4.6.2.3 The heat leakage of the calibrated box shall be noted in 
the test report.
    4.6.2.4 Refrigerant lines within the calibrated box shall be well 
insulated to avoid appreciable heat loss or gain.
    4.6.2.5 Instruments for measuring the temperature around the 
outside of the calibrated box to represent the enclosure temperature 
Ten shall be located at the center of each wall, ceiling, 
and floor.
    Exception: in the case where a clearance around the outside of the 
calibrated box, as indicated above, is reduced to less than 18 inches, 
the number of temperature-measuring devices on the outside of that 
surface shall be increased to six, which shall be treated as a single 
temperature to be averaged with the temperature of each of the other 
five surfaces. There will be six rectangular sections of equal area, 
and each of these six sections will have a temperature-measuring 
instrument located at its center. If the refrigeration system is 
mounted at the location that would cover the center of the face on 
which it is mounted, up to four temperature measurements shall be used 
on that face to represent its temperature. Each sensor shall be aligned 
with the center of the face's nearest outer edge and centered on the 
distance between that edge and the single-packaged unit (this is 
illustrated in Figure C5 when using surface temperature sensors), and 
they shall be treated as a single temperature to be averaged with the 
temperature of each of the other five surfaces. However, any of these 
sensors shall be omitted if either (a) the distance between the outer 
edge and the single packaged unit is less than one foot or (b) if the 
sensor location would be within two feet of any of the foot-square 
surfaces discussed below representing a warm discharge air impingement 
area. In this case, the remaining sensors shall be used to represent 
the average temperature for the surface.

[[Page 43820]]

    One of the following two approaches shall be used for the box 
external temperature measurement. Box calibration and system capacity 
measurement shall both be done using the same one of these approaches.
    4.6.2.5.1 Air temperature sensors. Each temperature sensor shall be 
at a distance of 6 inches from the calibrated box. If the clearance 
from a surface of the box (allowed for one surface only) is less than 
12 inches, the temperature measuring instruments shall be located 
midway between the outer wall of the calibrated box and the adjacent 
surface.
    4.6.2.5.2 Surface temperature sensors. Surface temperature sensors 
shall be mounted on the calibrated box surfaces to represent the 
enclosure temperature, Ten.
    Additional surface temperature sensors may be used to measure 
external hot spots during refrigeration system testing. If this is 
done, two temperature sensors shall be used to measure the average 
temperature of the calibrated box surface covered by the condensing 
section--they shall be centered on equal-area rectangles comprising the 
covered calibrated box surface whose common sides span the short 
dimension of this surface. Additional surface temperature sensors may 
be used to measure box surfaces on which warm condenser discharge air 
impinges. A pattern of square surfaces, with each surface measuring one 
foot square, shall be mapped out to represent the hot spot upon which 
the warm condenser air impinges. One temperature sensor shall be used 
to measure surface temperature at the center of each square (see Figure 
C5 of this section). A drawing showing this pattern and identifying the 
surface temperature sensors shall be provided in the test report. The 
average surface temperature of the overall calibrated box outer surface 
during testing shall be calculated as follows.
[GRAPHIC] [TIFF OMITTED] TN22JY22.005

Where:

Ai is the surface area of the ith of the six calibrated 
box surfaces;
Ti is the average temperature measured for the ith 
surface;
Aj is half of the surface area of the calibrated box covered by the 
condensing section;
T'j is the jth of the two temperature measurements 
underneath the condensing section;
T1 is the average temperature of the four or fewer measurements 
representing the temperature of the face on which the single-
packaged system is mounted, prior to adjustments associated with hot 
spots based on measurements Tj and/or Tk;
Ak is the area of the kth of n 1-square-foot surfaces 
used to measure the condenser discharge impingement area hot spot; 
and
T ''k is the kth of the n temperature measurements of the 
condenser discharge impingement area hot spot.

[[Page 43821]]

[GRAPHIC] [TIFF OMITTED] TN22JY22.006

BILLING CODE 6450-01-C
    4.6.2.6 Heating means inside the calibrated box shall be shielded 
or installed in a manner to avoid radiation to the Single-Packaged 
Dedicated System, the temperature measuring instruments, and to the 
walls of the box. The heating means shall be constructed to avoid 
stratification of temperature, and suitable means shall be provided for 
distributing the temperature uniformly.
    4.6.2.7 The average air dry-bulb temperature in the calibrated box 
during Single-Packaged Dedicated System tests and calibrated box heat 
leakage tests shall be the average of eight temperatures measured at 
the corners of the box at a distance of 2 inches to 4 inches from the 
walls. The instruments shall be shielded from any cold or warm surfaces 
except that they shall not be shielded from the adjacent walls of the 
box. The Single-Packaged Dedicated System under test shall be mounted 
such that the temperature instruments are not in the direct air stream 
from the discharge of the Single-Packaged Dedicated System.
    4.6.3 Calibration of the Calibrated Box. Calibration of the 
Calibrated Box shall occur prior to installation of the Single-Packaged 
Dedicated System. This shall be done either (a) prior to cutting the 
opening needed to install the Single-Packaged Dedicated System, or (b) 
with an insulating panel with the same thickness and thermal resistance 
as the box wall installed in the opening intended for the Single-
Packaged Dedicated System installation. Care shall be taken to avoid 
thermal shorts in the location of the opening either during calibration 
or during subsequent installation of the Single-Packaged Dedicated 
System. A calibration test shall be made for air movements comparable 
to those expected for Single-Packaged Dedicated System capacity 
measurement, i.e., with air volume flow rate within 10 percent of the 
air volume flow rate of the Single-Packaged Dedicated System 
evaporator.
    4.6.3.1 The heat input shall be adjusted to maintain an average box 
temperature not less than 25.0 [deg]F above the test enclosure 
temperature.
    4.6.3.2 The average dry-bulb temperature inside the calibrated box 
shall not vary more than 1.0 [deg]F over the course of the calibration 
test.
    4.6.3.3 A calibration test shall be the average of eleven 
consecutive hourly

[[Page 43822]]

readings when the box has reached a steady-state temperature condition.
    4.6.3.4 The box temperature shall be the average of all readings 
after a steady-state temperature condition has been reached.
    4.6.3.5 The calibrated box has reached a steady-state temperature 
condition when:
    4.6.3.5.1 The average box temperature is not less than 25.0 [deg]F 
above the test enclosure temperature.
    4.6.3.5.2 Temperature variations do not exceed 5.0 [deg]F between 
temperature measuring stations.
    4.6.3.5.3 Temperatures do not vary by more than 2.0 [deg]F at any 
one temperature-measuring station.
    4.6.4 Data to be Measured and Recorded. Refer to Table C2 in 
Section C7.2 of AHRI 1250-2020 for the required data that need to 
measured and recorded.
    4.6.5 Refrigeration Capacity Calculation.
    4.6.5.1 The heat leakage coefficient of the calibrated box is 
calculated by
[GRAPHIC] [TIFF OMITTED] TN22JY22.007

    4.6.5.2 For each Dry Rating Condition, calculate the Net Capacity 
by using the following:

qss = Kcb(Ten-Tcb) + 3.412 x E c

    (3) Representations. RSG may not make representations about the 
efficiency of a basic model listed in paragraph (1) of this Interim 
Waiver Order for compliance, marketing, or other purposes unless that 
basic model has been tested in accordance with the provisions set forth 
in this alternate test procedure and such representations fairly 
disclose the results of such testing.
    (4) This Interim Waiver Order shall remain in effect according to 
the provisions of 10 CFR 431.401(h).
    (5) This Interim Waiver Order is issued on the condition that the 
statements and representations provided by RSG are valid. If RSG makes 
any modifications to the controls or configurations of a basic model 
subject to this Interim Waiver Order, such modifications will render 
the waiver invalid with respect to that basic model, and RSG will 
either be required to use the current Federal test method or submit a 
new application for a test procedure waiver. DOE may rescind or modify 
this waiver at any time if it determines the factual basis underlying 
the petition for the Interim Waiver Order is incorrect, upon a 
determination that the results from the alternate test procedure are 
unrepresentative of a basic model's true energy consumption 
characteristics, or for other appropriate reasons. 10 CFR 
431.401(k)(1). Likewise, RSG may request that DOE rescind or modify the 
Interim Waiver Order if RSG discovers an error in the information 
provided to DOE as part of its petition, determines that the interim 
waiver is no longer needed, or for other appropriate reasons. 10 CFR 
431.401(k)(2).
    (6) Issuance of this Interim Waiver Order does not release RSG from 
the applicable requirements set forth at 10 CFR part 429.
    DOE makes decisions on waivers and interim waivers for only those 
basic models specifically set out in the petition, not future models 
that may be manufactured by the petitioner. RSG may submit a new or 
amended petition for waiver and request for grant of interim waiver, as 
appropriate, for additional basic models of single-packaged dedicated 
systems with multiple refrigeration circuits. Alternatively, if 
appropriate, RSG may request that DOE extend the scope of a waiver or 
an interim waiver to include additional basic models employing the same 
technology as the basic model(s) set forth in the original petition 
consistent with 10 CFR 431.401(g).

Signing Authority

    This document of the Department of Energy was signed on July 18, 
2022, by Kelly J. Speakes-Backman, Principal Deputy 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 July 19, 2022
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.

February 17, 2022

U.S. Department of Energy
Building Technologies Program, Test Procedure Waiver
1000 Independence Avenue SW, Mailstop EE-SB
Washington, DC 20585-0121

Re: Notice of petition for an alternate test procedure waiver and 
interim waiver. Request for public comment.

    Norlake, Inc., dba Refrigerated Solutions Group (RSG), 
respectfully requests a test procedure waiver and interim waiver 
pursuant to 10 CFR 431.401 with regards to 10 CFR 431 Appendix C of 
subpart R Uniform Test Method for the Measurement of Net Capacity 
and AWEF of Walk-In Cooler and Walk-In Freezer Refrigeration 
Systems. This request is for newly proposed test procedures for 
Walk-In Single Packaged Dedicated Refrigeration Systems.
    The reasons for the test procedure amendments are to account for 
the following;
    1. Testing multiple compressors and refrigeration circuits 
incorporated into a single system.
    2. Modifying the use of the 25' line set as these are single 
packaged dedicated systems not intended to be used with a line set.
    These systems meet the DOE definition of a Single-Packaged 
Dedicated System (single packaged assembly that includes one or more 
compressors, a condenser, a means for forced circulation of 
refrigerated air, and elements by which heat is transferred from air 
to refrigerant, without any element external to the system imposing 
resistance to flow of the refrigerated air.). Appendix C to Subpart 
R of Part 431 states that this equipment is to be evaluated using 
the test procedure set forth in AHRI 1250-2009 with certain 
modifications provided in the CFR. Neither 1250 nor the CFR address 
the prospect of multiple refrigeration circuits in one single-
packaged system. Therefore, we request a waiver to cover the 
procedure for testing systems with multiple refrigeration circuits.
    These systems incorporate multiple refrigeration circuits and 
operate on a single power feed. Each refrigeration circuit has its 
own compressor, expansion device, condenser, and evaporator circuits 
and may share condenser and evaporator fans and a single system 
controller. RSG is requesting a procedural waiver that allows for 
testing each refrigeration circuit under the same procedure as 
described in the CFR, but conduct the test simultaneously on each 
refrigeration circuit with duplicate monitoring of pressures, 
temperatures, and mass flow for each circuit. The power consumption 
of the total system will be collected. To determine the system AWEF, 
follow the procedures in the attached Alternate Procedure document. 
We feel this is keeping with the intent of the CFR while accounting 
for design characteristics of a multi-circuit system.
    With respect to the CFR and the reference of a 25' line set 
(C9.2) and section C3.3.3 referencing refrigerant charge, since one 
piece single-packaged systems are not intended to be remotely split 
via a line set, we request that the requirement for the 25' line set 
(C8.3 or 9.2) for this type of product be replaced with simply 
adding a mass flow meter to the liquid line between the heat 
exchanger and the expansion device. The existing suction line would 
not be disturbed for the test. The mass flow meter would be added 
with minimal additional liquid line (5 foot total maximum insulated 
with line size matching that supplied with the system) consistent 
with C3.4. The added refrigerant charge to account for the added 
liquid line extensions to and from the mass flow meter,

[[Page 43823]]

the mass flow meter itself and the sight glass would be determined 
using the pre-existing procedure in C3.3.3. It is also requested to 
relax the specification in C3.3.3 of 0.5 [deg]F tolerance for each 
on coil temp to 1 [deg]F as these temperature tolerances can be 
difficult to repeatedly achieve when the units are shut down, re-
plumbed and recharged and additionally, existing test condition 
tolerances of 1 [deg]F already exist for the indoor air temps which 
will affect the on-coil temps.
    The detailed alternate test procedures are in the attached 
Alternate Test Procedure document.
    Additionally, we recognize that the DOE has previously issued 
waivers for single package refrigeration systems to use the 
alternate energy determination methods specified in AHRI 1250-2020 
for single packaged systems, specifically air enthalpy methods 
(amongst others). Our lab is currently not set up to use this test 
method and the third-party agencies that we have contacted have 
replied that they are not able to conduct this test method at this 
time. We have conducted extensive testing using the method noted 
above and believe that it mirrors the intent of AHRI 1250-2009 and 
CFR modifications. Requiring alternate test methods from AHRI 1250-
2020 will place an undue burden both financially and time wise on 
RSG. We suggest the above alternative as a viable test method that 
mirrors the current test method described in the CFR and yields 
representative real life energy use/efficiency for the systems. Also 
going forward, the DOE could have alternate test methods for single 
packaged refrigeration systems that lend themselves to the current 
test method and not mandate this type of system to test methods that 
would require added expenses for test labs not currently set up for 
alternate test methods specified in AHRI 1250-2020.
    The basic models that this interm waiver and waiver would apply 
to are as follows, branded Norlake and Masterbilt;
    CPB050PC-S-0, CPB075PC-S-0, CPB100PC-S-0, CPF050PC-S-0, 
CPF075PC-S-0, CPF100PC-S-0, CPF150PC-S-4 and CPF200PC-S-4.
    Other manufactures of this class of equipment include but may 
not be limited to Heatcraft, Kolpak and Turbo-Air.
    Conclusion
    With the above noted information RSG requests that the DOE issue 
an Interim waiver and waiver to allow this modified energy 
efficiency test method as an alternate to the existing methods to 
account for single packaged walk-in refrigeration system 
construction. Failure to grant this request would have an economic 
hardship due to loss of revenue from sales of this product and/or 
significantly delay the release of the product to the market. Should 
the DOE require any additional information to move this forward we 
would be available and pleased to discuss.
Thank you for your consideration,
/s/
Bill Larson, CFSP
Senior Research and Development Engineer
Refrigerated Solutions Group
715-386-2323
RSG Alternate Test Procedure
    The alternate test procedure for the RSG basic models shall be 
tested using the test procedure for walk-in cooler refrigeration 
systems prescribed by DOE at 10 CFR part 431, subpart R, appendix C, 
except as detailed below. All other requirements of 10 CFR part 431, 
subpart R, appendix C, and DOE's regulations remain applicable.
    Modification to 10 CFR part 431, subpart R, appendix C:
* * * * *
    3.1.1. In Table 1, Instrumentation Accuracy, refrigerant 
temperature measurements shall have a tolerance of 0.5 F 
for unit cooler in/out. Temperature measurements used to determine 
water vapor content of the air shall be accurate to within 0.4 F, 1.0 F for all other temperature measurements.
* * * * *
    3.1.4. In Tables 2 through 14, the Test Condition Outdoor Wet Bulb 
Temperature requirement and its associated tolerance apply only to 
units with evaporative cooling and single-packaged dedicated systems.
* * * * *
    3.1.6. Tables 3, 4, 7, and 8 shall be modified to read as follows:

                                   Table 3--Fixed Capacity Matched Refrigerator System, Condensing Unit Located Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                         Unit  cooler    Unit  cooler
                                         air  entering   air  entering  Condenser  air  Condenser  air
           Test description                dry-bulb        relative     entering  dry-  entering  wet-      Compressor  capacity        Test objective
                                           ([deg]F)      humidity  (%)  bulb  ([deg]F)  bulb  ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power...................              35             <50  ..............  ..............  Compressor Off.............  Measure fan input
                                                                                                                                      wattage during
                                                                                                                                      compressor off
                                                                                                                                      cycle.
Refrigeration Capacity................              35             <50              90  \1\ 75, \2\ 65  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, input
                                                                                                                                      power, and EER at
                                                                                                                                      Rating Condition.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
1. Required only for evaporative Dedicated Condensing Units.
2. Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.


                                  Table 4--Fixed Capacity Matched Refrigerator System, Condensing Unit Located Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                         Unit  cooler    Unit  cooler
                                         air  entering   air  entering  Condenser  air  Condenser  air
           Test description                dry-bulb        relative     entering  dry-  entering  wet-      Compressor  capacity        Test objective
                                           ([deg]F)      humidity  (%)  bulb  ([deg]F)  bulb  ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power...................              35             <50  ..............  ..............  Compressor Off.............  Measure fan input
                                                                                                                                      wattage during
                                                                                                                                      compressor off
                                                                                                                                      cycle.
Refrigeration Capacity A..............              35             <50              95  \1\ 75, \2\ 68  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, input
                                                                                                                                      power, and EER at
                                                                                                                                      Rating Condition.
Refrigeration Capacity B..............              35             <50              59  \1\ 54, \2\ 46  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, and system
                                                                                                                                      input power at
                                                                                                                                      moderate
                                                                                                                                      condition.
Refrigeration Capacity C..............              35             <50              35  \1\ 34, \2\ 29  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, and system
                                                                                                                                      input power at
                                                                                                                                      cold condition.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
1. Required only for evaporative Dedicated Condensing Units.
2. Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.


[[Page 43824]]


                                     Table 7--Fixed Capacity Matched Freezer System, Condensing Unit Located Indoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                         Unit  cooler    Unit  cooler
                                         air  entering   air  entering  Condenser  air  Condenser  air
           Test description                dry-bulb        relative     entering  dry-  entering  wet-      Compressor  capacity        Test objective
                                           ([deg]F)      humidity  (%)  bulb  ([deg]F)  bulb  ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power...................             -10             <50  ..............  ..............  Compressor Off.............  Measure fan input
                                                                                                                                      wattage during
                                                                                                                                      compressor off
                                                                                                                                      cycle.
Refrigeration Capacity................             -10             <50              90  \1\ 75, \2\ 68  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, input
                                                                                                                                      power, and EER at
                                                                                                                                      Rating Condition.
Defrost Frost Load....................             -10         Various              90  \1\ 75, \2\ 68  System Dependent...........  Test according to
                                                                                                                                      Appendix C Section
                                                                                                                                      C11.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
1. Required only for evaporative Dedicated Condensing Units.
2. Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.


                                     Table 8--Fixed Capacity Matched Freezer System, Condensing Unit Located Outdoor
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                         Unit  cooler    Unit  cooler
                                         air  entering   air  entering  Condenser  air  Condenser  air
           Test description                dry-bulb        relative     entering  dry-  entering  wet-      Compressor  capacity        Test objective
                                           ([deg]F)      humidity  (%)  bulb  ([deg]F)  bulb  ([deg]F)
--------------------------------------------------------------------------------------------------------------------------------------------------------
Off Cycle Fan Power...................             -10             <50  ..............  ..............  Compressor Off.............  Measure fan input
                                                                                                                                      wattage during
                                                                                                                                      compressor off
                                                                                                                                      cycle.
Refrigeration Capacity A..............             -10             <50              95  \1\ 75, \2\ 68  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, input
                                                                                                                                      power, and EER at
                                                                                                                                      Rating Condition.
Refrigeration Capacity B..............             -10             <50              59  \1\ 54, \2\ 46  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, input
                                                                                                                                      power, and EER at
                                                                                                                                      Rating Condition.
Refrigeration Capacity C..............             -10             <50              35  \1\ 34, \2\ 29  Compressor On..............  Determine Net
                                                                                                                                      Refrigeration
                                                                                                                                      Capacity of Unit
                                                                                                                                      Cooler, input
                                                                                                                                      power, and EER at
                                                                                                                                      Rating Condition.
Defrost Frost Load....................             -10         Various              95  \1\ 75, \2\ 68  System Dependent...........  Test according to
                                                                                                                                      appendix C Section
                                                                                                                                      C11.
--------------------------------------------------------------------------------------------------------------------------------------------------------
Note:
1. Required only for evaporative Dedicated Condensing Units.
2. Maximum allowable value for Single-Packaged Dedicated Systems that do not use evaporative Dedicated Condensing Units, where all or part of the
  equipment is located in the outdoor room.

* * * * *
BILLING CODE 6450-01-P

[[Page 43825]]

[GRAPHIC] [TIFF OMITTED] TN22JY22.008


[[Page 43826]]


[GRAPHIC] [TIFF OMITTED] TN22JY22.009


[[Page 43827]]


[GRAPHIC] [TIFF OMITTED] TN22JY22.010

    C5.1.1 Single-Package Refrigerant Enthalpy method shall determine 
gross refrigeration capacity by measuring the enthalpy change and the 
mass flow rate of the refrigerant using a single set of measurements.
    C5.1.2 Calibrated Box method shall determine net refrigeration 
capacity by measuring the heat input to the calibrated box, including 
thermal transfer through the calibrated box walls.
    C5.1.3 Indoor Air Enthalpy method shall determine net refrigeration 
capacity of Single-package System and input power in accordance with 
ASHRAE 37-2009, Figure C4, and the following modifications.
    C5.1.3.1 Net refrigeration capacity is determined by measuring 
airflow rate and the dry-bub temperature and water vapor content of the 
air that enters and leaves the coil. Air enthalpies shall be determined 
in accordance with ANSI ASHRAE 41.6. Entering air is to be sufficiently 
dry as to not produce frost on the Evaporator coil. Therefore, only 
sensible capacity measured by dry bulb change shall be used to 
calculate capacity.
    C5.1.4 Testing Sequence. The primary test method shall be used to 
measure the capacity for Rating Condition A prior to set-up of the 
Single-Package Refrigerant Enthalpy Measurement. After set-up of the 
Refrigerant Enthalpy method, the Net Capacity shall be measured using 
both the primary test method and the Refrigerant Enthalpy method. The 
Net Capacity measurement using the Refrigerant Enthalpy method shall be 
within 6 percent of the net capacity measurement using the primary 
method.
    If a capacity balance within tolerance is not initially achieved, 
take steps to reduce the thermal losses of the single-package system 
evaporator compartment by sealing air gaps and potentially adding more 
external insulation. If using the Calibrated Box method as the primary 
method, achieving a capacity balance may require conducting the 
calibration with calibrated box insulation material at the same average 
temperature as during capacity measurement, or using multiple 
calibrations conducted at different average insulation material 
temperatures and using these data to construct a correlation for the 
calibration coefficient Kcb as a function of average 
insulation temperature. The official performance measurements are based 
on the primary method testing without any air gap sealing and 
additional external insulation used to achieve the 6 percent energy 
balance in place.
    C5.1.5 The refrigerant enthalpy method Net Capacity shall be 
calculated from the Gross Capacity Measurement as follows.

Qss,2 = Qref-3.412 x EFcomp,on-Qsploss

Where Qsploss represents the single-package system thermal losses 
through the walls of the evaporator side of the single-package 
system to the condenser side and to the exterior ambient, and shall 
be calculated as follows.

Qsploss = UAcond x (Tcondside-Tevapside) + UAamb x (Tamb-Tevapside)

Where:

UAcond and UAamb are, for the condenser/
evaporator partition and the evaporator compartment walls exposed to 
ambient air, respectively, the product of the overall heat transfer 
coefficient and surface area of the unit as manufactured, i.e. 
without external insulation that might have been added during the 
test;
Tevapside is the air temperature in the evaporator 
compartment;
Tcondside is the air temperature in the condenser 
compartment; and
Tamb is the air temperature outside the single-package 
system.

The Net Capacity to be used in AWEF calculations shall be the net 
capacity measured using the primary method.

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    C9.2.1.5.1 Air temperature sensors.
    Each temperature sensor shall be at a distance of 6 inches from the 
calibrated box. If the clearance from a surface of the box (allowed for 
one surface only) is less than 12 inches, the temperature measuring 
instruments shall be located midway between the outer wall of the 
calibrated box and the adjacent surface.
    C9.2.1.5.2 Surface temperature sensors.
    Surface temperature sensors shall be mounted on the calibrated box 
surfaces to represent the enclosure temperature Ten.
    Additional surface temperature sensors may be used to measure 
external hot spots during refrigeration system testing. If this is 
done, two temperature sensors shall be used to measure the average 
temperature of the calibrated box surface covered by the condensing 
section--they shall be located centered on equal-area rectangles 
comprising the covered calibrated box surface whose common sides span 
the short dimension of this surface. Additional surface temperature 
sensors may be use to measure box surfaces on which warm condenser 
discharge air impinges. A pattern of square surfaces measuring one foot 
square shall be mapped out to represent the hot spot upon which the 
warm condenser air impinges. One temperature sensor shall be used to 
measure surface temperature at the center of each square (see Figure 
C5). A drawing showing this pattern and identifying the surface 
temperature sensors shall be provided in the test report. The average 
surface temperature of the overall calibrated box outer surface during 
testing shall be calculated as follows.

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Where:
Ai is the surface area of the ith of the six 
calibrated box surfaces;
Ti is the average temperature measured for the 
ith surface;
Aj is half of the surface area of the calibrated box 
covered by the condensing section;
T'j is the jth of the two temperature 
measurements underneath the condensing section;
T1 is the average temperature of the four or fewer 
measurements representing the temperature of the face on which the 
single-packaged system is mounted, prior to adjustments associated 
with hot spots based on measurements Tj and/or 
Tk;
Ak is the area of the kth of n 1-square-foot 
surfaces used to measure the condenser discharge impingement area 
hot spot;
T''k is the kth of the n temperature 
measurements of the condenser discharge impingement area hot spot; 
and

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[FR Doc. 2022-15726 Filed 7-21-22; 8:45 am]
BILLING CODE 6450-01-C