LG AMNW07GDBL1 Service Manual page 63

Part 5. Trouble Shooting
Display
Title
code
Over-current on AC → DC
27
converter circuit
WARNING
Before checking PCB or each outdoor electric parts, wait for 3 minutes after the power is off. When measuring at standby state
of power supply, after checking the measurement mode of the meter, be careful of the short-circuits with other parts.
Is the unit properly
installed?
Is the reactor
normal?
Is IGBT Part
is normal?
Yes
Recheck power and
installation condition
Copyright ©2014 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Cause of error
• Overload operation
(Outdoor fan constraint,
screened, blocked)
• Wrong application of
Reactor Spec.
• Burned PCB internal
parts (PSC Module)
• Check fan locking
• Remove blockings around heat exchanger
• Maintain distance between outdoor unit
and the wall
• Check pipe folding and abnormality
• Check service valve lock
• Remedy : remove cause of error
• Check Reactor spec:1 1A/13mH
• Remedy : replace reactor.
• Check IGBT part
resistance measurements
at power-on standby state
100Ω
• Remedy : replace PCB Assembly.
- 62 -
Check point & Normal condition
• Check outdoor fan constraint/ screened/ flow
structure
• Check Reactor Spec: 11A/ 13mH
• Check for PCB internal part burn
• Inspecting PCB IGBT part
1. Remove the connectors to the PCB.
2. Set Multi-tester as Resistance
measurement mode
3. Measure Resistance of Gate-collector,
Emitter-collector.
4. If the measurements are 1MΩ ,
the parts are decided as burned.
IGBT
LGE Internal Use Only