10 CFR Part 431, Appendix A
Note: Prior to October 31, 2023, representations with respect to the energy use of envelope components of walk-in coolers and walk-in freezers, including compliance certifications, must be based on testing conducted in accordance with the applicable provisions of 10 CFR part 431, subpart R, appendix A, revised as of January 1, 2022. Beginning October 31, 2023, representations with respect to energy use of envelope components of walk-in coolers and walk-in freezers, including compliance certifications, must be based on testing conducted in accordance with this appendix.
DOE incorporated by reference in § 431.303 the entire standard for ASTM C1199-14 and NFRC 102-2020. However, certain enumerated provisions of these standards, as set forth in sections 0.1 and 0.2 of this appendix are inapplicable. To the extent that there is a conflict between the terms or provisions of a referenced industry standard and the CFR, the CFR provisions control.
(a) Section 1 Scope, is inapplicable,
(b) Section 4 Significance and Use is inapplicable,
(c) Section 7.3 Test Conditions, is inapplicable,
(d) Section 10 Report, is inapplicable, and
(e) Section 11 Precision and Bias, is inapplicable.
(a) Section 1 Scope, is inapplicable,
(b) Section 4 Significance and Use, is inapplicable,
(c) Section 7.3 Test Conditions, is inapplicable,
(d) Section 10 Report, is inapplicable,
(e) Section 11 Precision and Bias, is inapplicable,
(f) Annex A3 Standard Test Method for Determining the Thermal Transmittance of Tubular Daylighting Devices, is inapplicable, and
(g) Annex A5 Tables and Figures, is inapplicable.
This appendix covers the test requirements used to measure the energy consumption of the components that make up the envelope of a walk-in cooler or walk-in freezer.
The definitions contained in § 431.302 are applicable to this appendix.
4.1 Automatic door opener/closer means a device or control system that “automatically” opens and closes doors without direct user contact, such as a motion sensor that senses when a forklift is approaching the entrance to a door and opens it, and then closes the door after the forklift has passed.
4.2 Percent time off (PTO) means the percent of time that an electrical device is assumed to be off.
4.3 Rated power means the input power of an electricity-consuming device as specified on the device's nameplate. If the device does not have a nameplate or such nameplate does not list the device's input power, then the rated power must be determined from the device's product data sheet, literature, or installation instructions that come with the device or are available online.
4.4 Rating conditions means, unless explicitly stated otherwise, all conditions shown in table A.1 of this appendix.
Internal Temperatures (cooled space within the envelope)
| Cooler Dry-Bulb Temperature | 35 °F |
|---|---|
| Freezer Dry-Bulb Temperature | −10 °F |
External Temperatures (space external to the envelope)
Freezer and Cooler Dry-Bulb Temperatures | 75 °F
Determine the U-factor of the entire door or display panel, including the frame, in accordance with the specified sections of NFRC 102-2020 and ASTM C1199-14 at the temperature conditions listed in table A.1 of this appendix.
5.2.1 For display doors and display panels, thermal transmittance, Udd or Udp, respectively, shall be the standardized thermal transmittance, UST, determined per section 5.1 of this appendix.
5.2.2 For non-display doors, thermal transmittance, Und, shall be the standardized thermal transmittance, UST, determined per section 5.1 of this appendix.
5.2.3 Projected area of the test specimen, As, in ft 2, as referenced in ASTM C1199-14.
6.1.1 Determine the U-factor of the display panel in accordance with section 5.1 of this appendix, in units of Btu/(h-ft 2- °F).
6.1.2 Calculate the temperature differential, ΔTdp, °F, for the display panel, as follows:
6.1.3 Calculate the conduction load through the display panel, Qcond-dp, Btu/h, as follows:
6.1.4 Calculate the total daily energy consumption, Edp, kWh/day, as follows:
6.2.1.1 Determine the U-factor of the display door in accordance with section 5.1 of this appendix, in units of Btu/(h-ft 2- °F).
6.2.1.2 Calculate the temperature differential, ΔTdd, °F, for the display door as follows:
6.2.1.3 Calculate the conduction load through the display doors, Qcond,dd, Btu/h, as follows:
6.2.1.4 Calculate the total daily energy consumption due to conduction thermal load, Edd,thermal, kWh/day, as follows:
Electrical components associated with display doors could include but are not limited to: heater wire (for anti-sweat or anti-freeze application); lights; door motors; control system units; and sensors.
6.2.2.1 Select the required value for percent time off (PTO) for each type of electricity-consuming device per table A.2 of this appendix, PTOt (%).
| Device | Temperature condition | Controls, timer, or other auto-shut-off system | Percent time off value (%) |
|---|---|---|---|
| Lights | All | Without With | 25 50 |
| Anti-sweat heaters | All Coolers Freezers | Without With With | 0 75 50 |
| Door motors | All | | 97 | |
| All other electricity-consuming devices | All | Without With | 0 25 |
6.2.2.2 Calculate the power usage for each type of electricity-consuming device, Pdd,comp,u,t, kWh/day, as follows:
6.2.2.3 Calculate the total electrical energy consumption for interior and exterior power, Pdd,tot,int (kWh/day) and Pdd,tot,ext (kWh/day), respectively, as follows:
6.2.2.4 Calculate the total electrical energy consumption, Pdd,tot, (kWh/day), as follows:
Calculate the additional refrigeration energy consumption due to thermal output from electrical components sited inside the display door, Cdd,load, kWh/day, as follows:
Calculate the total energy, Edd,tot, kWh/day,
6.3.1.1 Determine the U-factor of the non-display door in accordance with section 5.1 of this appendix, in units of Btu/(h-ft 2- °F).
6.3.1.2 Calculate the temperature differential of the non-display door, ΔTnd, °F, as follows:
6.3.1.3 Calculate the conduction load through the non-display door: Qcond,nd, Btu/h,
6.3.1.4 Calculate the total daily energy consumption due to thermal load, End,thermal, kWh/day, as follows:
Electrical components associated with non-display doors comprise could include, but are not limited to: heater wire (for anti-sweat or anti-freeze application), lights, door motors, control system units, and sensors.
6.3.2.1 Select the required value for percent time off for each type of electricity-consuming device per table A.2 of this appendix, PTOt (%).
6.3.2.2 Calculate the power usage for each type of electricity-consuming device, Pnd,comp,u,t, kWh/day, as follows:
6.3.2.3 Calculate the total electrical energy consumption for interior and exterior power, Pnd,tot,int, kWh/day, and Pnd,tot,ext, kWh/day, respectively, as follows:
6.3.2.4 Calculate the total electrical energy consumption, Pnd,tot, kWh/day, as follows:
Calculate the additional refrigeration energy consumption due to thermal output from electrical components associated with the non-display door, Cnd,load, kWh/day, as follows:
Calculate the total energy, End,tot, kWh/day, as follows:
[88 FR 28839, May 4, 2023, as amended at 88 FR 73216, Oct. 25, 2023]