ErrorCodeDoctor
Panasonic Air Conditioner F91 error code
The F91 error means your Panasonic air conditioner detected an abnormality in the refrigerant cycle. This is a serious fault that can indicate a refrigerant leak, a blockage in the refrigerant circuit, or a faulty expansion valve. Refrigerant issues must always be handled by a licensed technician as they require specialist equipment and certification.
Common causes
- Refrigerant has leaked from the system reducing the charge level
- Blockage in the refrigerant circuit preventing normal flow
- Expansion valve has malfunctioned affecting refrigerant flow
- Refrigerant circuit component has failed
How to fix it
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1
Turn off the unit at the circuit breaker immediately
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2
Do not attempt to use the unit — running with an abnormal refrigerant cycle can damage the compressor
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3
Contact a licensed technician to inspect the refrigerant circuit and repair the fault
Related Panasonic Air Conditioner error codes
F91 error — frequently asked questions
What does the F91 error mean on a Panasonic air conditioner?
A refrigerant cycle abnormality was detected
What causes the F91 error?
The F91 error is usually caused by: Refrigerant has leaked from the system reducing the charge level; Blockage in the refrigerant circuit preventing normal flow; Expansion valve has malfunctioned affecting refrigerant flow; Refrigerant circuit component has failed.
Can I fix the F91 error myself?
This is rated a hard fix — it often requires tools, parts, or experience, and may be safer left to a professional technician.
How much does it cost to fix the F91 error?
Fixing the F91 error on a Panasonic air conditioner typically costs $150–$500, depending on parts and whether you do it yourself or hire a technician.
Is it safe to keep using my air conditioner with the F91 error?
We'd recommend addressing the F91 error before continuing to use the air conditioner, since hard-rated issues often involve a real fault rather than a minor glitch.