Indoor unit shows CH10 and may not operate or may shut down shortly after starting.

Safety: Disconnect power at the breaker before working on the indoor unit.

Steps:

• Check for obstructions: Remove the front cover and filters. Inspect the blower wheel for plastic bags, insulation, or other debris. Remove any obstruction.
• Spin test: Gently spin the blower wheel by hand. It should rotate smoothly with minimal resistance. Grinding or stiffness indicates bad bearings.
• Inspect motor mount: Ensure the motor bracket is secure and not bent, which can cause the wheel to rub the housing.
• Check wiring: Verify the fan motor connector is firmly attached to the indoor PCB and that no wires are pinched.
• Test run: Restore power and run the unit in FAN mode. If the fan fails to start or stops quickly and CH10 reappears, turn power off.
• Replace motor if locked: If the blower is free but the motor does not run or overheats, replace the LG indoor fan motor assembly.

Technician recommended: If a new motor does not resolve CH10, the indoor PCB fan driver circuit may be defective and should be replaced by a professional.