Water Pump - LG Therma V ZHBW056A0 Service Manual

1.2 Water Pump

Water pump always
running while system
operation
DIP Switch No.5
is set to OFF ?
Water pump
is not correct
* : It is normal condition that water pump runs or stops during system operation (including compressor start-up)
due to specific control logic.
• Water pump does not because of mechanical defects of water pump or wrong wiring at the water pump.
• To correct mechanical defects, contact official After Service Center and replace the water pump.
• To correct wrong wiring, check if wires 'CN_MOTOR1' connector on the unit PCB and water pump
A
terminal box (black plastic box at the water pump) are connected firmly. Also, check wires are
electrically connected by measuring resistance of each wires (if electrically connected exactly,
resistance should be 0 ohm).
• Unit PCB can not make control signal or wrong wiring at the water pump.
• To correct unit PCB's making control signal, first check the signal level. Use electric voltage meter
and measure voltage at 'CN_MOTOR1' connector on the unit PCB. If measured value is not
B 220-240 V~ while 'Water Pump Operating' is displayed at control panel, the unit PCB is in trouble.
In this case, contact official After Service Center and replace the unit PCB.
• To correct wrong wiring, please refer Ⓐ.
Start
NO
compressor start-up
YES
NO
Heating
Operation
YES
NO
YES
control by
unit PCB
B
*Water pump runs
NO
and stops while
YES
END
(it is normal
condition)
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Only training and service purposes.
NO
Water pump always
stop while system
operation
YES
Water pump does
not working
A