System displays CH28 and stops operating.
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: Turn off power at the disconnect and breaker. Current sensors are part of the high-voltage circuit.
Basic checks:
- Inspect wiring: Open the outdoor panel and check that the main power wires pass correctly through the current sensor (CT) and that no wires are loose or burned.
- Look for shorts: Inspect compressor and fan wiring for signs of short circuits or melted insulation.
- Power reset: After correcting any obvious wiring issues, restore power and test.
Technician involvement: If CH28 persists, the current sensor or outdoor PCB must be tested and likely replaced by a qualified technician.
Repair Difficulty
Required Part
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