LG Air Conditioner Error Code 110

Error code 110 on an LG air conditioner indicates a three-phase power wiring fault on the Sub1 outdoor unit. The system has detected either a reversed phase sequence or a missing phase. This prevents the outdoor unit from operating safely and requires inspection of the power cable connections and the incoming supply voltage before the unit can restart.

Yes, running a three-phase compressor with reversed phase or a missing phase can cause serious mechanical and electrical damage. A reversed phase causes rotating components to spin in the wrong direction, which can destroy compressor internals very quickly. The unit's protection circuit triggers error 110 to prevent this damage, so the system should not be forced to operate until the wiring fault is corrected.

If the fix is simply correcting the phase wiring order at the terminal block, the cost is typically just a service call fee, which can range from $75 to $200 depending on your area. If a blown fuse or failed breaker pole is involved, parts and labor could add $50 to $150 or more. If the incoming power cable itself is damaged and needs replacement, costs could range from $200 to $600 or higher depending on cable length and labor involved.

Start by shutting off power to the outdoor unit at the disconnect switch and verifying the phase order of the three power cables at the Sub1 outdoor unit terminal block against the wiring diagram. Use a phase sequence tester or multimeter to confirm all three phases are present and in the correct L1, L2, L3 order. If a phase is missing, trace the fault back through the disconnect, fuses, and breaker panel. Correcting the wiring order or restoring the missing phase should clear the fault after power is restored.

A simple reset will not permanently clear error code 110 if the underlying wiring fault still exists. The phase detection circuit will re-detect the reverse phase or missing phase condition as soon as the unit attempts to start and the error will return. The fault must be corrected at the power supply or terminal block before a reset will be effective.