Panasonic CS-PS9JKT Service Manual page 60

14.4.17 F91 (Refrigeration Cycle Abnormality)
Malfunction Decision Conditions
•
During cooling, compressor frequency = Fcmax.
•
During cooling and heating operation, running current: 0.65A < I < 1.65A.
•
During cooling, indoor intake - indoor pipe < 4°C
Malfunction Caused
•
Refrigerant shortage (refrigerant leakage)
•
Poor compression performance of compressor.
•
2/3 way valve closed.
•
Detection error due to faulty indoor intake air or indoor pipe temperature sensors.
Troubleshooting
When F91 indication happens
Check the indoor air intake and pipe
temperature sensors.
Does it conform to the sensor
characteristic chart?
2/3-way valve opened?
Check for gas leaking.
Oil oozing out from the 2/3 way valve?
Capillary tube or dryer clogged?
Charge for a specified amount of fresh
refrigerant.
Refrigerant cycle abnormality error again?
NO
NO
YES
YES
NO
YES
YES
NO
For safety reason and to prevent component
breakdown, always switch off the power
before remove and connect the component.
•
Replace the indoor intake air or pipe
temperature sensor
•
Open 2/3 way valve
•
Repair the pipe flare or union nuts.
Reclaim and recharge refrigerant.
•
Replace the capillary tube or dryer.
•
Replace outdoor unit PCB &
compressor
•
Procedure complete
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