Liquid Compression Protection Function 2; Defrost Control - Daikin CTXU25G2V1B Service Manual

Control Specification

3.10 Liquid Compression Protection Function 2

Outline In order to obtain the dependability of the compressor, the compressor must be stopped
according to the conditions of the temperature of the outdoor air and outdoor heat exchanger.
Detail
Compressor operation turns OFF under the conditions that the system is in cooling operation
and outdoor air temperature is below 10°C.

3.11 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 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 30 minutes of accumulated fine pass since the start of the
operation or ending the defrosting.
Conditions for Canceling Defrost
The judgment must be made with heat exchanger temperature. (40 class : 4°C~12°C, 50 class :
4°C~15°C)
47
Operation stops depending on the outdoor air temperature.
Frequency
60 sec.
ON
Compressor
OFF
ON
Four way valve
OFF
ON
Fan
OFF
450 pulse
Operating room
electronic expansion
valve opening
Operation stopped room
140 pulse
electronic expansion
valve opening
0 Hz
120 sec. 530 sec.
5 sec.
120 sec.
40 class: 350 pulse 350 pulse
50 class: 300 pulse
40 class: 160 pulse
50 class: 200 pulse
SiBE12-908
PI control
30 sec.
5 sec.
450 pulse
Initial opening
Initial opening
0 pulse
(R10618)
Function and Control