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Control Specification
SiMT041311E
53
Function and Control
2.10 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 defrosting.
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 25 minutes of accumulated time have passed since the start of the operation, or
ending the previous defrosting.
Conditions for Cancelling Defrost
The judgement is made with the outdoor heat exchanger temperature. (6 ~ 30°C)
Frequency
Compressor
Four way valve
Fan
ON
OFF
ON
OFF
ON
OFF
0 Hz
0 Hz
80 Hz
30 Hz
8 sec.
350 pulse
200 pulse
350 pulse
400 pulse
450 pulse
Initial opening
PI control
8 sec.
90
sec.
30
sec.
60
sec.
(R19675)
Electronic expansion
valve opening
50 sec.
570 sec.