Viconics HP727S - Manual (Page 13)

1 1 3 3
10. DEFROST CYCLE SEQUENCE:
The HP727S has an evaporator temperature sensor to control the defrost cycle when the compressor operates.
Whenever the compressor starts, the evaporator fan starts also.
The fan and the defrost cycle are controlled as follow.
60 F 42 F 44 F 52 F 24 F
Evaporator temperature
Fan operation Defrost cycle operation
Fan on Compressor still ON
Compressor OFF
Fan always on
during defrost cycle