01. Power supply path not reaching indoor unit
Book a checkThe indoor unit does not boot because control power is not reaching it. This often happens at the isolator, terminal, or supply handoff point.
- Display stays blank at all times.
- No beep when remote buttons are pressed.
- Issue can appear right after a power event or switch change.
Solution: We verify incoming supply to the indoor control path first, then restore stable power handoff before any part recommendation.
Remarks: Approving board replacement before supply checks can add cost without fixing the real issue.