Unit displays P4; compressor may not run or may shut down intermittently
Safety Warning
This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.
If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.
Possible Causes
How to Fix / Troubleshooting
Safety first: Turn off power before cleaning or opening the outdoor unit.
Steps to check:
- 1. Improve ventilation: Ensure the outdoor unit has adequate clearance and is not enclosed in a tight space.
- 2. Clean condenser coil: Remove debris and gently wash the coil fins.
- 3. Check PCB cooling: Some models have a small fan or rely on airflow across the PCB. Ensure nothing is blocking vents and that any small fan is running.
When to call a technician: Persistent P4 suggests overheating of the inverter module. A technician should check heatsink compound, module mounting, and possibly replace the inverter PCB.
Repair Difficulty
Required Part
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