Defrost Control - Daikin FTXG20LV1BW Service Manual

SiBE041401E

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 defrosting.
Detail Conditions for Starting Defrost
Conditions for Canceling Defrost
The judgment is made with the outdoor heat exchanger temperature. (B°C)
A (minutes)
B (°C)
C (Hz)
D (Hz)
E (seconds)
F (seconds)
G (seconds)
H (seconds)
J (pulse)
K (pulse)
L (pulse)
Function and Control
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 A minutes of accumulated time have passed since the start of the operation, or
ending the previous defrosting.
Frequency
ON
Compressor
OFF
ON
Four way valve
OFF
ON
Fan
OFF
Electronic expansion
valve opening
20/25/35 class
28
4 ~ 18
76
86
50
60
480
60
450
350
450
C Hz
0 Hz
F sec.
E sec. G sec.
5 sec.
J pulse
K pulse
50 class
44
4 ~ 12
55
90
60
120
340
50
450
350
450
Control Specification
D Hz
0 Hz
H sec.
5 sec.
L pulse
Initial opening
PI control
(R19555)
44