34
PMGB0126A rev.2 - 11/2006
TROUBLESHOOTING
Troubleshooting
Problem Causes Solution
No Activation of 
Unit Operation 
Indicator
Electrical Power Source Failure• Wait for Recovering of Electrical Power Supply•
Blow off Main 
Switch Fuse
•
Electrical Short Circuit to Earth•
Replace the Main Switch Fuse after Eliminating 
Earthing
•
Faulty Compressor Motor• Replace the Compressor and the main Switch Fuse•
Faulty Indoor Fan Motor•
Replace the indoor Fan Motor and the Main Switch 
Fuse
•
Blow off 
Control 
Circuit Fuse
•
Electrical Short Circuit between Different Phase 
Wires
•
Replace the Fuse•
Electrical Short Circuit to Earth• Replace the Fuse•
Faulty Magnetic Switch for Compressor Motor• Replace the magnetic Switch and the Fuse•
Faulty Transformer of Indoor Unit
• Replace the Transformer•
Disconnected Cable of Remote Control Panel to the Indoor Unit• Replace the Cable•
Abnormality of Remote Control Switch•
Check the connection of the Remote Control Cable. 
Replace the Remote Control Switch.
•
Incorrect 
activation of 
PCB
•
Disconnected Wire(s) to PCB of Indoor Unit• Connect Wire(s) to the PCB•
Faulty PCB of Indoor Unit• Replace the PCB of Indoor Unit•
No Activation of 
Compressor and 
Fan Motor (In the 
Case of Indicator 
Activation of 
Remote Control 
Switch)
Faulty Indoor Fan Motor• Replace the Indoor Fan Motor•
Faulty Outdoor Fan Motor• Replace the Outdoor Fan Motor•
Faulty magnetic switch for Outdoor Fan Motor• Replace the magnetic switch of the Outdoor Unit•
Faulty Compressor Motor of Compressor• Replace the Compressor•
Faulty Magnetic Switch for Compressor Motor• Replace the magnetic switch•
Incorrect activation of PCB•
Disconnected Wire(s) to PCB• Connect Wire(s) to the PCB•
Faulty PCB of Indoor Unit• Replace the PCB for Indoor Unit•
In case of 3~ unit installed 
for first time, if an “05” code 
is indicated on remote 
control switch
•
Phase protection Relay•
Switch off the power supply of the unit, reverse 2 of 
the phases, reapply the power and restart the unit
•
Flickering of 
Indicator and Lamp 
of “RUN” Switch
Faulty Internal Thermostat for Indoor Fan Motor
• Replace the Indoor Fan Motor•
Disconnected Wires between Indoor Unit and Outdoor Unit• Connect the Wires Correctly•
Incorrect Activation of PCB
•
Disconnected Wire(s) to the PCB• Connect Wire(s) to the PCB•
Faulty PCB of Indoor Unit• Replace the PCB for Indoor Unit•
Tripped Float Switch for Drain (only in RCI Units)
•
Adjust level of the Drain pan Repair or Replace the 
Drain Discharge Mechanism. Remove the Clogged 
Material
•
No Speed Change 
of Fan In spite of 
Adjustment
Abnormality of Thermistor 
for Air Inlet Discharge Temp.
•
Faulty Thermistor
• Replace the Thermistor•
Disconnected Wire of Thermistor
• Connect the Wire to the Thermistor•
Faulty Remote Control Switch• Replace the Remote Control Switch•
Faulty PCB of Indoor Unit• Replace the PCB of the Indoor Unit•
No Stopping 
and Starting of 
Compressor In 
spite of Adjusting 
Thermostat
Abnormality of Thermistor 
for Air Inlet Temperature
•
Faulty Thermistor
• Replace the Thermistor•
Disconnected Wire of Thermistor
• Connect the Wire of Thermistor•
Faulty “TEMP” Switch of Remote Control Switch• Replace “TEMP” Switch of Remote Control Switch•
Faulty PCB of Indoor Unit• Replace PCB of the Indoor Unit•
Faulty Cable of Remote Control Switch• Replace the Cable•
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