U1

Abnormal High Pressure (63H Tripped)

Description

The outdoor unit's high-pressure switch (63H) has tripped due to excessive refrigerant pressure.

Appliance Error Codes Details

Error Code
U1
Error Name
Abnormal High Pressure (63H Tripped)
Appliance Type
air_conditioner
Brand
Mitsubishi
Severity
high

Additional Troubleshooting

1. Turn off the unit
2. Check that indoor and outdoor units have adequate airflow and no short-cycling of air
3. Clean the outdoor heat exchanger and air filters if dirty
4. Contact service to check the pressure switch and refrigerant charge

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Author: Pavel Volkov
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