Defrost Control - Daikin FLKS25BVMB Service Manual

SiBE05-311

3.11 Defrost Control

Outline Heat Pump Only
Defrosting is carried out by the cooling cycle (reverse cycle). The defrosting time or outdoor
heat 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. (4˚C~22˚C)
Function and Control
Frequency
45sec.
ON
Compressor
OFF
ON
Four way valve
OFF
ON
Fan
OFF
Electronic expansion
30pps
valve opening
0Hz
60sec.
650sec.
5sec.
55pps
Control Specification
45sec.
5sec.
40pps 55pps
Initial opening
PI control
(R2945)
39