F3 (4 flashes) — Communication error between Power module and main PCB board

What does F3 mean?

There is a communication breakdown between the Power Module and the main Printed Circuit Board (PCB) in the outdoor unit. This prevents them from working together correctly.

• Communication wiring disconnected or damaged
• Faulty Outdoor PCB
• Faulty IPM Module

Click steps to track your progress.

1. 1

   Ensure the power switch is off before checking connections.

2. 2

   Carefully check and reinsert the terminals connecting the Power Module and the Outdoor PCB.

3. 3

   Replace any visibly damaged wiring.

4. 4

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