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93 

  During operating of cooling and heating, when IPM temperature data (100°C) is detected by the IPM temperature 

sensor. 
Multi Models only 
o  Compressor Overheating: During operation of cooling and heating, when the compressor OL is activated. 
o  Heat Sink Overheating: During operation of cooling and heating, when heat sink temperature data (90°C) is 

detected by the heat sink temperature sensor. 

  IPM overheats due to short circuit of hot discharge air flow. 

  IPM overheats due to defective of outdoor fan motor. 

  IPM overheats due to defective of internal circuitry of IPM. 

  IPM overheats due to defective IPM temperature sensor. 

Multi Models Only 
o  Compressor OL connector poor contact. 
o Compressor 

OL 

faulty. 

 
Troubleshooting 
 

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

94 

  During operation of cooling and heating, when compressor tank temperature data (112°C) is detected by the 

compressor tank temperature sensor. 

  Faulty compressor tank temperature sensor 

  2/3 way valve closed 

 Refrigerant 

shortage 

(refrigerant leakage) 

  Faulty outdoor unit PCB 

 Faulty 

compressor 

 
Troubleshooting 
 

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

95 

  During operation of cooling and heating, when an input over-current (X value in Total Running Current Control) is 

detected by checking the input current value being detected by current transformer (CT) with the compressor 
running. 

 
Malfunction Caused 

 Excessive 

refrigerant. 

  Faulty outdoor unit PCB. 

 
Troubleshooting 
 

 

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

96 

Malfunction Decision Conditions 
During startup and operation of cooling and heating, when inverter DC peak data is received by the outdoor internal 
DC Peak sensing circuitry. 
 
Malfunction Caused 

  DC current peak due to compressor failure. 

  DC current peak due to defective power transistor(s). 

  DC current peak due to defective outdoor unit PCB. 

  DC current peak due to short circuit. 

 
Troubleshooting