Reverse Phase Detector Circuit Fault

What does F7 mean?

The reverse phase detection circuit on the outdoor unit's printed circuit board (PCB) is malfunctioning. This means the unit cannot correctly identify or react to phase reversal conditions in the incoming power supply.

1. 1

   Inspect the outdoor unit PCB for any visible damage or burn marks in the area of the phase detection circuit.

2. 2

   Verify input voltage to the outdoor unit PCB is within specified limits.

3. 3

   Check continuity of the wiring from the main power input to the phase detection circuit on the PCB.