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13.5.24 F99 (DC Peak Detection)
Malfunction Decision Conditions
During startup and operation of cooling, 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
When F99 indication happens
Reset the error code and turn on the unit
again
Is there a sound when compressor starts?
NO (Compressor stops)
YES
●
Outdoor electronic circuit defect due to
power transistor short
●
Replace the outdoor unit PCB
●
Amplification IC defect
●
Diode defect
●
Defect in microcontroller
●
Replace the outdoor unit PCB
Is compressor vibration even?
NO (Quite a lot of vibration at
start operation)
YES
●
●
Excessive amount of refrigerant
Check the compressor winding resistance:
●
Turn off the power and disconnect
the harnesses U, V and W
●
Measure the winding resistance
between U-V, V-W and W-U
YES
Is there no change even if all refrigerant
is discharged?
NO (Normal)
YES (Stops after 2, 3 seconds
of noise during operation)
Are the compressor’s winding resistance
(U-V, V-W or U-W) shorted?
Compressor defective due to
mechanical locked
Replace compressor
NO (Normal)
●
●
Compressor defective due to winding
shorted
Replace compressor
●
●
For safety reason and to prevent component
breakdown, always switch off the power
before remove and connect the component.
Caution
