Defrost Control - Daikin FTXS09HVJU Service Manual

Control Specification (15/18/24 Class)

4.11 Defrost Control

Defrosting is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor heat
Outline
exchanger temperature must be more than its fixed value when finishing.
Detail Conditions for Starting Defrost
The starting conditions must be made with the outdoor air temperature and heat exchanger
temperature. Under the conditions that the system is in heating operation, 6 minutes after the
compressor is started and more than 44 minutes of accumulated time pass since the start of the
operation or ending the defrosting.
Conditions for Canceling Defrost
The judgment must be made with heat exchanger temperature. (39°F~54°F / 3.8~12.2°C)
56
Frequency
60sec.
ON
Compressor
OFF
ON
Four way valve
OFF
ON
Fan
OFF
Electronic expansion
450pulse
valve opening
0Hz
120sec.
460 sec.
5sec.
450pulse
SiUS04-904
PI control
45sec.
5sec.
450pulse
Initial opening
(R4082)
Function and Control