LG Therma V AHBW Series - Water Pump

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1.2 Water Pump
• 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_W/PUMP (A)’ connector on the unit PCB and water
pump 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, re-
sistance 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_W/PUMP (A)’ connector on the unit PCB. If measured value is not
220 V ~ 240 V AC while ‘Water Pump Operating Icon ( )’ 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 Ⓐ.
* : It is normal condition that water pump runs or stops during system operation (including compressor start-up)
due to specific control logic.
Start
Water pump
control by
unit PCB
is not correct
Water pump does
not working
A
B
YES
YES
NO
NO
END
(it is normal
condition)
NO
YES
YES
YES
NO
NO
Water pump always
running while system
operation
Water pump always
stop while system
operation
Heating
Operation
DIP Switch No.5
is set to
OFF ?
*Water pump runs
and stops while
compressor start-up
A
B