Defrost Control - Daikin G-Series Service Manual

Control Specification

3.10 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
Conditions for Canceling Defrost
The target heat exchanger temperature as the canceling condition is selected in the range of
E
88
The starting conditions is 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 30 minutes of accumulated time pass since the start of the operation, or ending
the previous defrosting.
°C according to the outdoor temperature.
Frequency
ON
Compressor
OFF
ON
Four way valve
OFF
ON
Fan
OFF
Electronic expansion
valve opening
(operating room)
Electronic expansion
valve opening
(stop room)
40 class 50 class
A (Hz)
70
B (Hz)
86
C (pulse)
350
D (pulse)
160
E (˚C)
4 ~ 12 4 ~ 15
A
Hz
0 Hz
60 sec. 120 sec. 530 sec.
5 sec.
450 pulse 350 pulse
C
pulse
D
140 pulse
pulse
48
70
300
200
B
Hz
30 sec.
5 sec.
450 pulse
Initial opening
Initial opening
0 pulse
Function and Control
SiBE12-933_A
PI control
(R12739)