Panasonic CS-PS9JKT Service Manual page 59

14.4.16 F90 (Power Factor Correction Protection)
Malfunction Decision Conditions
•
During startup and operation of cooling and heating, when Power Factor Correction (PFC) protection circuitry at
the outdoor unit main PCB senses abnormal high DC voltage level.
Malfunction Caused
•
DC voltage peak due to power supply surge.
•
DC voltage peak due to compressor windings not uniform.
•
Faulty outdoor PCB.
Troubleshooting
When abnormality indication starts again
Check the supply voltage
Supply voltage as specified?
Operate the system. Verify PFC abnormality by measuring DC
voltage between P (+) and N (-) terminal at the outdoor unit PCB.
Is the DC voltage between P (+) and N (-) terminal normal
between 285~315Vdc)?
Check the compressor winding resistance:
•
Turn off the power supply and disconnect the harness U, V
and W.
•
Measure the winding resistance between U-V,V-W and W-U
Are the compressor's winding resistance (U-V, V-W, W-U)
•
Replace the outdoor unit PCB.
NO
YES
NO
NO
YES
59
For safety reason and to prevent
component breakdown, always
switch off the power before remove
and connect the component.
Correct the power supply
YES
(~28Vdc)
•
Defect in PFC circuitry
•
Replace the outdoor unit PCB
•
Replace the compressor