4-36. DEFROST CONTROL.
This task covers:
Tool Kit, service, refrigeration unit
Rock Salt (Appendix F, Item 15)
Insulated Container (Appendix E)
Power off at power source.
Both front door assemblies removed. See para 4-17.
Left side door assembly removed. See para 4-19.
General Safety Instructions:
Disconnect input power to the unit before performing any internal maintenance.
Voltages used can kill. Shutting the unit off at the thermostat does not disconnect
(1) Check the two screws (1, Figure 4-32) attaching the defrost control (2) to the control box (3). Tighten if
(3) Install both front door assemblies. See para 4-17.
(4) Install left side door assembly. See para 4-19.
(1) Mix rock salt, Ice, and water in Insulated container to form brine solution. Bring temperature of brine solution
below 26 degrees Fahrenheit (-3 degrees Centigrade).
(2) Remove sensing bulb (4, Figure 4-32) from mounting bracket on left side of the outdoor coil assembly. Sub-
merge sensing bulb in brine solution.
(3) Apply power to system. Set thermostat to heat.
HIGH VOLTAGE is used in the operation of this equipment. DEATH ON CONTACT
or severe injury may result if personnel fail to observe safety precautions.
(4) Rotate clock motor shaft (5), observing cam position in window (8) below shaft. Stop switch lever (9) just
before deep slot (7).