Control Specification
SiBE121135
116
Function and Control
4.10 Defrost Control
Outline
Defrosting is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor
heat exchanger temperature must be more than a certain value to finish.
Detail
Conditions for Starting Defrost
The starting conditions are determined with the outdoor temperature and the outdoor heat
exchanger temperature.
The system is in heating operation.
The compressor operates for 6 minutes.
More than 38 minutes of accumulated time pass after the start of the operation, or ending
the previous defrosting.
Conditions for Canceling Defrost
The target heat exchanger temperature as the canceling condition is selected in the range of
4 ~ 12
°C according to the outdoor temperature.
Frequency
Compressor
Four way valve
Fan
ON
OFF
ON
OFF
ON
OFF
0 Hz
A
Hz
5 sec.
400 pulse
350 pulse
450 pulse
Initial opening
0 pulse
160 pulse
Initial opening
PI control
5 sec.
60 sec.
60 sec.
530 sec.
120 sec.
(R17160)
B
Hz
40/50/52/58 class
62
80
68/75 class
54
82
80/90 class
39
62
A
(Hz)
B
(Hz)
Outdoor electronic
expansion valve
opening (operating
room)
Outdoor electronic
expansion valve
opening (stop room)