Fujitsu Mini Split Error Code 31: How to Fix It

Q: What causes Fujitsu error code 31 to appear?

Error code 31 is triggered when the outdoor unit's high-pressure switch detects excessive refrigerant pressure, usually caused by dirty condenser coils, blocked airflow, faulty condenser fan, or refrigerant system issues.

Q: Can I reset Fujitsu error code 31 without fixing the problem?

You can temporarily reset the error, but it will return if the underlying cause isn't addressed. Simply resetting without fixing the high-pressure condition can lead to compressor damage and expensive repairs.

Q: How often should I clean my Fujitsu mini split condenser coil?

Clean the outdoor condenser coil at least twice yearly - before summer and after fall. In dusty or high-pollen areas, monthly cleaning may be necessary to prevent high-pressure issues.

Q: Is Fujitsu error code 31 dangerous to ignore?

Yes, ignoring this error is dangerous as it indicates potentially damaging high refrigerant pressure. The system shuts down to protect the compressor from permanent damage, which would require expensive replacement.

Q: How much does it cost to fix Fujitsu error code 31?

DIY cleaning costs $10-30 for supplies. Professional service calls range from $150-300. If parts like the condenser fan motor or pressure switch need replacement, costs can reach $300-800 including labor.

Abstract

Fujitsu mini split error code 31 indicates the outdoor unit's high-pressure switch has tripped, meaning the refrigerant pressure has exceeded safe limits. This critical error shuts down the system to prevent compressor damage and typically points to airflow restrictions, dirty coils, or refrigerant issues.