U1 - Abnormal high pressure (High pressure switch 63H activated)

What does U1-1 mean?

The system has detected excessively high pressure in the refrigerant circuit, triggering the high-pressure switch (63H) as a safety measure. This can lead to system shutdown.

• Overcharge of refrigerant.
• Blockage in the refrigerant lines or coils.
• Outdoor fan not operating correctly.

Click steps to track your progress.

1. 1

   Turn off the air conditioning system and wait for at least 30 minutes.

2. 2

   Inspect the outdoor unit for any debris or blockages that might restrict airflow.

3. 3

   Ensure any accessible service valves are fully open.

4. 4

   If the problem continues, contact a certified HVAC technician for diagnosis.