Defrost Control - LG R410A Service Manual

2.2 Defrost control

Start conditions
Defrost control starts if one of below conditions are satisfied.
1) Case 1 : DIP switch 1,2 ON
-2°C ≤ air temp. : hex pipe temp < -7°C
-7°C < air temp. < -2°C : hex pipe temp < (air temp. -9°C)
air temp. ≤ -7°C : hex pipe temp < (air temp. -11°C)
2) Case 2 : DIP switch 1 or 2 OFF
0°C ≤ air temp. : hex pipe temp < -7°C
-5°C < air temp.<0°C : hex pipe temp < (air temp. -9°C)
air temp. ≤ -5°C : hex pipe temp < (air temp. -11°C)
Component
Inv Compressor
Fan
Main LEV
4 way valve
Subcooling LEV
Hot gas bypass
valve
Indoor unit
Fan
Thermo on unit
LEV
Thermo off unit
LEV
I Ending condition
1) All Heat exchanger pipe temperature are above 15˚C for 30 sec.
2) The running time of defrost operation is over 30% of the total heating time
Starting
37Hz + 37Hz
0 Hz
Full open
On ¡ off
min.
On
Starting
Off
Oil return Oil return operation
pulse
Oil return operation
Heating close pulse
Running
90Hz + 90Hz
High pressure High pressure
control
Full open
Off
min.
On
Running
Off
pulse
Heating close pulse
pulse
Ending
20Hz + 20Hz
control
Base pulse
On
min.
On
Ending
Off
Return to
base pulse
Service Manual 95
Function