5. Trouble Shooting 
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21
DC PEAK
(IPM Fault)
• Instant over current
• Over Rated current
• Poor insulation of IPM
• An instant over current in the U,V,W phase
- Comp lock
- The abnormal connection of U,V,W
• Over load condition
- Overcharging of refrigerant
Pipe length.
Outdoor Fan is stop
• Poor insulation of compressor
Display
code
Title Cause of error Check point & Normal condition
Is installation 
condition normal?
No 
Yes 
Yes 
Recheck power and  installation condition
1. Check Pipe clogging/distortion
2. Check Covering (Indoor/Outdoor Unit)
3. Check EEV connector assemble condition/normal  
    operation
4. Check refrigerant pressure
  Reassemble or manage if abnormality found
1. Check resistance between each terminal of compressor 
    (0.34~0.35   7%)
2. Check insulation resistance between compressor        
    terminal and pipe (over 50M   )
  Replace compressor if abnormality found
Are the resistance 
Between each phase and
 insulation resistance of Inverter 
compressor normal?
No 
Yes 
1. Check inverter PCB assembly U,V,W connector  
    connection condition
2. Check wire disconnection and wiring
3. Check compressor terminal connection condition 
    (bad contact)
  Reassemble if abnormality found
Is compressor 
Wire connection 
condition normal?
No 
Yes 
Check inverter PCB assembly IPM normality
  Replace inverter PCB assembly
Is inverter PCB assembly normal?
No