Error Diagnosis And Countermeasure Flow Chart - LG Therma V ZHBW056A0 Service Manual

Code
Description
No.
Bad communication
05
between main PCB
assembly(Inverter)
and main PCB
assembly(Heater)
53
n Error diagnosis and countermeasure flow chart
Control panel
displays CH05?
Yes
Is main PCB(Heater)
LED blinking?
Yes
Check if the
transmission cable is
properly connected to
terminal block of
main PCB(Heater) and
main PCB(Inverter)
Yes
Cause
• The connector for transmission is
disconnected
• The connecting wires are
misconnected
• The communication line is broken
• main PCB(Heater) is abnormal
• main PCB(Inverter) is abnormal
No
Check the main power
No
supply at the unit
terminal block?
Yes
Is main circuit breaker off?
Yes
Improper connection of power supply cable
Main power supply problem
No
Re-connect transmission cable
main PCB(Inverter) fault
Replace after checking
main PCB(Heater) fault
Replace after checking
• Wire connection between control panel
and main PCB 2 should be tight
No
No
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Normal Condition
Replace main main PCB(Inverter)
Reconnect transmission cable
between main main PCB(Inverter)
and control panel
Replace main PCB(Inverter) after
checking
Replace TRANS after checking
Check the insulation of inverter
Check the capacity of main circuit
breaker and replace if required
If all ok,
Turn on main circuit breaker