LG Air Conditioner Error Code 23

Error code 23 on an LG air conditioner indicates that the outdoor unit's inverter compressor DC link voltage is too low. The fault is specifically triggered when the DC bus does not charge properly after the starting relay turns on. The system shuts down to protect the compressor and inverter components from operating under unsafe electrical conditions.

The error itself is a protective shutoff designed to prevent equipment damage, so the system is safer when it is displaying this fault than if it were running with inadequate voltage. The danger lies in attempting to service the inverter components inside the outdoor unit without proper precautions, since the DC link capacitors store high voltage and must be fully discharged before any internal work begins.

Repair cost depends on the failed component. A service call to diagnose and correct a wiring or supply voltage issue typically runs in the range of $75 to $200. Replacing a starting relay or capacitors may add $100 to $300 in parts and labor. An inverter power module or control board replacement is the most expensive scenario, often ranging from $300 to $700 or more depending on the unit and availability of parts.

The first step, checking that the supply voltage is within the 220V±10% or 240V±10% range, can be done by a knowledgeable homeowner with a multimeter. However, work beyond that point involves high-voltage DC capacitors inside the outdoor unit that retain dangerous charge even after power is removed. Internal component inspection and replacement should be handled by a qualified technician.

A reset may temporarily clear the fault and allow a restart attempt, but if the underlying cause such as low supply voltage, a faulty relay, or a failed capacitor is still present, the error will return quickly. Clearing the code without addressing the root cause can result in repeated shutdowns and potential damage to the inverter or compressor over time.