U1 - 3 red flashes, 2 green flashes — High pressure trip

What does U1 mean?

This error indicates a high-pressure condition within the system, which can be caused by several factors including outdoor fan failure or blockages.

• Outdoor fan failure
• Blocked coil
• Blockage within the system
• Blocked filters on the indoor unit (in heating mode)

Click steps to track your progress.

1. 1

   Check if the outdoor fan is running correctly.

2. 2

   Inspect the outdoor coil for dirt or obstructions.

3. 3

   Ensure indoor unit filters are clean.

4. 4

   Check for any visible blockages in refrigerant lines (requires professional).