§ 429.53 Walk-in coolers and walk-in freezers. ( a ) *Determination of represented value.* ( 1 ) The requirements of § 429.11 apply to walk-in coolers and walk-in freezers; and
( 2 ) For each basic model of walk-in cooler and walk-in freezer refrigeration system, the annual walk-in energy factor (AWEF) must be determined either by testing, in accordance with § 431.304 of this chapter and the provisions of this section, or by application of an AEDM that meets the requirements of § 429.70 and the provisions of this section. ( i ) *Applicable test procedure.* If AWEF or AWEF2 is determined by testing, test according to the applicable provisions of § 431.304(b) of this chapter with the following equipment-specific provisions. ( A ) *Dedicated condensing units.* Outdoor dedicated condensing refrigeration systems that are also designated for use in indoor applications must be tested and rated as both an outdoor dedicated condensing refrigeration system and an indoor dedicated refrigeration system.
( B ) *Matched refrigeration systems.* A matched refrigeration system is not required to be rated if the constituent unit cooler(s) and dedicated condensing unit have been tested as specified in § 431.304(b)(4) of this chapter. However, if a manufacturer wishes to represent the efficiency of the matched refrigeration system as distinct from the efficiency of either constituent component, or if the manufacturer cannot rate one or both of the constituent components using the specified method, the manufacturer must test and rate the matched refrigeration system as specified in § 431.304(b)(4) of this chapter.
( C ) *Detachable single-packaged dedicated systems.* Detachable single-packaged dedicated systems must be tested and rated as a single-packaged dedicated systems using the test procedure in § 431.304(b)(4) of this chapter.
( D ) *Attached split systems.* Attached split systems must be tested and rated as dedicated condensing units and unit coolers using the test procedure in § 431.304(b)(4) of this chapter.
( ii ) *Units to be tested.* ( A ) If the represented value for a given refrigeration system basic model is determined through testing, the general requirements of § 429.11 apply; and
( B ) For each basic model, a sample of sufficient size shall be randomly selected and tested to ensure that any represented value of AWEF or other measure of energy efficiency of a basic model for which consumers would favor higher values shall be less than or equal to the lower of: ( 1 ) The mean of the sample, where: And *x̄* is the sample mean; n is the number of samples; and xi is the ith sample, or,
( 2 ) The lower 95 percent confidence limit (LCL) of the true mean divided by 0.95, where: And *x̄* is the sample mean; s is the sample standard deviation; n is the number of samples; and t0.95 is the t statistic for a 95% one-tailed confidence interval with n-1 degrees of freedom (from appendix A to subpart B).
( C ) The represented value of net capacity shall be the average of the capacities measured for the sample selected.
( iii ) *Alternative efficiency determination methods.* In lieu of testing, pursuant to the requirements of § 429.70 and the provisions of this section, a represented value of AWEF for a basic model of a walk-in cooler or walk-in freezer refrigeration system may be determined through the application of an AEDM, where: ( A ) Any represented value of AWEF or other measure of energy efficiency of a basic model for which consumers would favor higher values shall be less than or equal to the output of the AEDM and greater than or equal to the Federal standard for that basic model.
( B ) The represented value of net capacity must be the net capacity simulated by the AEDM.
( 3 ) For each basic model of walk-in cooler and walk-in freezer display and non-display door, the daily energy consumption must be determined by testing, in accordance with § 431.304 of this chapter and the provisions of this section, or by application of an AEDM that meets the requirements of § 429.70 and the provisions of this section. ( i ) *Applicable test procedure.* Prior to October 31, 2023 use the test procedure for walk-ins in 10 CFR part 431, subpart R, appendix A, revised as of January 1, 2022, to determine daily energy consumption. Beginning October 31, 2023, use the test procedure in part 431, subpart R, appendix A of this chapter to determine daily energy consumption.
( ii ) *Units to be tested.* For each basic model, a sample of sufficient size shall be randomly selected and tested to ensure that any represented value of daily energy consumption of a basic model or other measure of energy use for which consumers would favor lower values shall be greater than or equal to the higher of: ( A ) The mean of the sample, where: Equation 3 to Paragraph (a)(3)(ii)(A) And *x̄* is the sample mean, *n* is the number of samples, and *x̄* i is the ith sample; or,
( B ) The upper 95 percent confidence limit (UCL) of the true mean divided by 1.05, where: Equation 4 to Paragraph (a)(3)(ii)(B) And *x̄* is the sample mean, *s* is the sample standard deviation; *n* is the number of samples, and t−0.95 is the statistic for a 95 percent one-tailed confidence interval with n-1 degrees of freedom (from appendix A to this subpart).
( 4 ) For each basic model of walk-in cooler and walk-in freezer panel and non-display door, the R-value must be determined by testing, in accordance with § 431.304 of this chapter and the provisions of this section. ( i ) *Applicable test procedure.* Prior to October 31, 2023, use the test procedure for walk-ins in 10 CFR part 431, subpart R, appendix B, revised as of January 1, 2022, to determine R-value. Beginning October 31, 2023, use the test procedure in appendix B to subpart R of part 431 of this chapter to determine R-value.
( ii ) *Units to be tested.* For each basic model, a sample of sufficient size shall be randomly selected and tested to ensure that any represented value of R-value or other measure of efficiency of a basic model for which consumers would favor higher values shall be less than or equal to the lower of: ( A ) The mean of the sample, where: Equation 5 to Paragraph (a)(4)(ii)(A) And *x̄* is the sample mean, *n* is the number of samples, and *x̄* i is the ith sample; or,
( B ) The lower 95 percent confidence limit (LCL) of the true mean divided by 0.95, where: Equation 6 to Paragraph (a)(4)(ii)(B) And *x̄* is the sample mean, *s* is the sample standard deviation; *n* is the number of samples, and t−0.95 is the statistic for a 95 percent one-tailed confidence interval with n-1 degree of freedom (from appendix A to this subpart).
( b ) *Certification reports.* ( 1 ) The requirements of § 429.12 apply to manufacturers of walk-in cooler and walk-in freezer panels, doors, and refrigeration systems, and;
( 2 ) Pursuant to § 429.12(b)(13), a certification report must include the following public product-specific information: ( i ) For doors: The door type, R-value of the door insulation, and a declaration that the manufacturer has incorporated the applicable design requirements. In addition, for those walk-in coolers and walk-in freezers with transparent reach-in doors and windows, the glass type of the doors and windows (*e.g.,* double-pane with heat reflective treatment, triple-pane glass with gas fill), and the power draw of the antisweat heater in watts per square foot of door opening must also be included.
( ii ) For walk-in cooler and walk-in freezer panels: The R-value of the insulation.
( iii ) For walk-in cooler and walk-in freezer refrigeration systems: The installed motor's functional purpose (*i.e.,* evaporator fan motor or condenser fan motor), its rated horsepower, and a declaration that the manufacturer has incorporated the applicable walk-in-specific design requirements into the motor.
( 3 ) Pursuant to § 429.12(b)(13), starting on June 5, 2017, a certification report must include the following public product-specific information in addition to the information listed in paragraph (b)(2) of this section: ( i ) For walk-in cooler and walk-in freezer doors: The door energy consumption and rated surface area in square feet.
( ii ) For refrigeration systems that are medium-temperature dedicated condensing units, medium-temperature single-package dedicated systems, or medium-temperature matched systems: The refrigeration system AWEF, net capacity, the configuration tested for certification (*e.g.,* condensing unit only, unit cooler only, single-package dedicated system, or matched-pair), and if an indoor dedicated condensing unit is also certified as an outdoor dedicated condensing unit and, if so, the basic model number for the outdoor dedicated condensing unit.
( 4 ) Pursuant to § 429.12(b)(13), starting on June 5, 2017, a certification report must include the following product-specific information in addition to the information listed in paragraphs (b)(2) and (3) of this section: ( i ) For walk-in cooler and walk-in freezer doors: the rated power of each light, heater wire, and/or other electricity consuming device associated with each basic model of display and non-display door; and whether such device(s) has a timer, control system, or other demand-based control reducing the device's power consumption.
( 5 ) When certifying compliance to the AWEF refrigeration standards for WICF refrigeration systems except those specified in (b)(3)(ii) of this section, a certification report must include the following public product-specific information in addition to the information listed in paragraph (b)(2) of this section: For refrigeration systems that are low-temperature dedicated condensing units, low-temperature matched systems, low-temperature single-package dedicated systems, or medium and low-temperature unit coolers: The refrigeration system AWEF, net capacity, the configuration tested for certification (*e.g.,* condensing unit only, unit cooler only, single-package dedicated system, or matched-pair), and if an indoor dedicated condensing unit is also certified as an outdoor dedicated condensing unit and, if so, the basic model number for the outdoor dedicated condensing unit.
[81 FR 95799, Dec. 28, 2016, as amended at 88 FR 28835, May 4, 2023]