F3 (4 flashes) — Communication fault between Power module and outdoor PCB

What does F3 (4 flashes) mean?

This error indicates a communication failure specifically between the Power Module and the main outdoor Printed Circuit Board (PCB).

• Outdoor PCB is broken
• IPM module is broken
• Communication wiring is disconnected

Click steps to track your progress.

1. 1

   Turn off the power switch before checking connections.

2. 2

   Verify that the terminals CN23/CN24 (Outdoor PCB) and CN10/CN11 (IPM module) are tightly connected.

3. 3

   Check that the connection between the power module and the power lines (P/N) is secure.

4. 4

   Turn the power back on and check if the error is resolved.