Panasonic CS-E7PKR Service Manual page 135

16.4.23 F91 (Refrigeration Cycle Abnormality)
Malfunction Decision Conditions

The input current is low while the compressor is running at higher than the setting frequency.
Malfunction Caused

Lack of gas.

3-way valve close.
Troubleshooting
Note: Some error code might not applicable for this model.
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