6.4.5 Walk-In Coolers and Walk-In Freezers

Site-assembled or site-constructed walk-in coolers and walk-in freezers shall conform to the following requirements:

1. Shall be equipped with automatic door closers that firmly close walk-in doors that have been closed to within 1 in. of full closure.

   Exception to 6.4.5(a)

   Doors wider than 3 ft 9 in. or taller than 7 ft.

2. Doorways shall have strip doors (curtains), spring-hinged doors, or other method of minimizing infiltration when doors are open.
3. Walk-in coolers shall contain wall, ceiling, and door insulation of at least R-25 and at least R-32 for walk-in freezers.

   Exception to 6.4.5(c)

   Glazed portions of doors or structural members.

4. Walk-in freezers shall contain floor insulation of at least R-28.
5. Evaporator fan motors that are less than 1 hp and less than 460 V shall use electronically commutated motors (brushless direct-current motors) or three-phase motors.
6. Lights shall use light sources with an efficacy of 40 lm/W or more, including ballast losses (if any). Light sources with lower may be used in conjunction with a timer or device that turns off the lights within 15 minutes of when the walk-in cooler or walk-in freezer is not occupied by people.
7. Transparent reach-in doors for walk-in freezers, and windows in walk-in freezer doors, shall be of triple-pane glass, either filled with inert gas or with heat-reflective treated glass.
8. Transparent reach-in doors for walk-in coolers, and windows in walk-in cooler doors, shall be double-pane glass with heat-reflective treated glass and gas filled, or they shall be triple-pane glass, either filled with inert gas or with heat-reflective treated glass.
9. Antisweat heaters without antisweat heater controls shall have a total door rail, glass, and frame heater power draw of ≤7.1 W/ft² of door opening for walk-in freezers and 3.0 W/ft² of door opening for walk-in coolers.
10. Antisweat heater controls shall reduce the energy use of the antisweat heater as a function of the relative humidity in the air outside the door or to the condensation on the inner glass pane.
11. Condenser fan motors that are less than 1 hp shall use electronically commutated motors, permanent split-capacitor-type motors, or three-phase motors.
12. All walk-in freezers shall incorporate temperature-based defrost termination control with a time limit default. The defrost cycle shall terminate first on an upper temperature limit breach and second upon a time limit breach.