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SERVICE FUNCTIONS
9
9-1. CHANGE IN DEFROST SETTING
Changing defrost finish temperature
<JS> To change the defrost finish temperature, cut/solder the JS wire of the outdoor inverter P.C. board (Refer to 10-6.1.).
Jumper
Defrost finish temperature
MUZ-GS30/36NA
MUZ-GS30/36NAH
MUY-GS30/36NA
JS
Soldered
(Initial setting)
50°F (10°C)
None
(Cut)
64°F (18°C)
9-2. PRE-HEAT CONTROL SETTING
Prolonged low load operation, in which the thermostat is OFF for a long time, at low outside temperature [32°F (0°C) or
less] may cause the following troubles. To prevent those troubles, activate the pre-heat control.
1) If moisture gets into the refrigerant cycle and freezes, it may interfer the start-up of the compressor.
2) If liquid refrigerant collects in the compressor, a failure in the compressor may occur.
The pre-heat control turns ON when the compressor temperature is 68°F (20°C) or below. When the pre-heat control
turns ON, the compressor is energized. (About 70 W)
Pre-heat control setting
<JK>
ON: To activate the pre-heat control, cut JK wire of the inverter P.C. board.
OFF: To deactivate the pre-heat control, solder JK wire of the inverter P.C. board.
(Refer to 10-6.1)
Jumper
Pre-heat control setting
MUZ-GS30/36NA
MUZ-GS30/36NAH
MUY-GS30/36NA
JK
Soldered
Deactivated
(Initial setting)
Cut
Activated
NOTE:
When the inverter P.C. board is replaced, check the jumper wires, and cut/solder them if necessary.
MUZ-GS30NA MUZ-GS30NAH MUZ-GS36NA MUZ-GS36NAH MUY-GS30NA MUY-GS36NA
OBH875
