innovair Inverter FLEX24 DEV24H2R18, Service Manual

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Troubleshooting ：
Outdoor heat exchanger is blocked
Indoor heat exchanger is blocked.
Ambient temperature is out of the
operation range
H4
Overload
Too much charging quantity.
Error still exists?
Remove the obstacle
Remove the obstacle
Normal protection. No
need to handle it.
Release a proper amount
of refrigerant
Replace the drive board
Replace the compressor
YES
YES
YES
YES
YES
NO
NO
NO
NO
3.4.10 “H5” IPM Protection
Error display: ODU mainboard LED displayer
Error judgment condition and method:
When power is connected and drive chip received IPM lead F0 that is of low level, than it is IPM module
malfunction. System will shut down for protection.
Possible reason:
Compressor 3-phase wire connection is lack of phase or phase-reversed.
System is overloaded and compressor current is too large.
Drive board IPM module is damaged.
SERVICE MANUAL
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