System shows CH33 and stops operation.
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: Do not attempt to adjust refrigerant charge yourself. Always shut off power before cleaning coils.
Homeowner actions:
- Clean filters and coils: Clean indoor filters and, if accessible, gently clean the indoor coil. Clean the outdoor coil thoroughly.
- Check service valves (visual only): Ensure valve caps are installed and there are no obvious signs of tampering or leaks.
- Power reset: After cleaning, power off for 10 minutes, then on, and test.
Technician tasks: A professional should measure system pressures, superheat/subcooling, and verify that the expansion device and refrigerant charge are correct. They will also confirm that all service valves are fully open.
Repair Difficulty
Required Part
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