ED — Serial communication error (Outdoor unit Multi controller board-Power board communication trouble)

What does ED mean?

This error indicates a communication problem between the outdoor unit's multi-controller board and the power board. The air conditioning system will automatically stop operating.

• Loose wiring connection between the multi-controller board and the power board.
• Faulty multi-controller board in the outdoor unit.
• Faulty power board in the outdoor unit.

Click steps to track your progress.

1. 1

   Check the wiring connections between the multi-controller board and the power board in the outdoor unit.

2. 2

   Ensure all cable connectors are fully seated and free from corrosion.

3. 3

   Power cycle the outdoor unit by turning off the main breaker for a few minutes, then turning it back on.

4. 4

   If the error persists, contact a qualified service technician to inspect and potentially replace faulty boards.