LG Mini Split H23 Error Code

Updated 2026-08-30 · review status: manual-verified · reviewed by MiniSplitDecoder Editorial Team Last verified: 2026-08-30

Check your model first

  • LG General Wall Mounted-Inverter Type service manual (via manualsdump)
  • SplitAtlas (LG support table, Mega R-32)
  • MyPros+ / HVAC Wiz NYC / BC Wide (heat pump rows)

Match the model on your equipment label to the linked manufacturer documentation. The same code can mean different things across model families.

Quick answer

LG H23/CH23 means an outdoor inverter DC-link voltage fault - the DC bus voltage between the rectifier and compressor inverter drifted out of the safe range (usually too low). Reset once at the breaker; also note any flickering home lights or tripped breakers. Inverter-board and supply diagnosis is technician/electrician work, not DIY.

Severity: high · DIY difficulty: easy

Safety

Stop at the breaker power-cycle and any plug-accessible checks (filters, remote settings, visible wiring). The outdoor unit's capacitor holds a lethal charge and the refrigerant circuit is both pressurized and (on R-32 units) flammable — opening panels or servicing the sealed system is licensed-technician work (EPA 608).

What H23 means

H23 (CH23) means an outdoor inverter DC-link voltage abnormality: LG's wall-mounted inverter service manual's troubleshooting section covers CH23 with DC-link voltage checks (about 140 VDC threshold and supply-voltage verification), and LG's support table describes compressor DC-link high/low voltage. Most references read it as DC link LOW voltage caused by undervoltage supply or a failing inverter circuit; a few series rows also list DC-link overvoltage.

Code meaning varies by series

  • LG General Wall Mounted-Inverter Type service manual (via manualsdump): CH23 troubleshooting: check DC link voltage and power source - low voltage (~140 VDC) condition
  • SplitAtlas (LG support table, Mega R-32): CH23 = outdoor inverter compressor DC-link high/low voltage - supply-voltage problems or internal inverter circuit fault
  • MyPros+ / HVAC Wiz NYC / BC Wide (heat pump rows): CH23 = DC link low voltage - internal electrical voltage dropped too low to run the compressor safely; usually power-supply related

First checks before service

This page currently documents the safe reset triage. If the code returns, use the linked source manual or a qualified technician for code-specific diagnosis.

  1. 1. One-time fault event (power disturbance or transient sensor reading) common DIY

    Check: Power-cycle at the breaker/disconnect (or unplug for CPAP), restore, and run the system while watching for the code.

    Fix: If the code does not return after a full run cycle, the fault was transient — monitor, no repair needed.

  2. 2. Fault persists after a clean reset occasional pro only

    Check: If the code returns immediately or every session, note the conditions (startup, heating, after rain).

    Fix: A persisting code points at the component the manual assigns to this code — that repair is technician territory.

Related codes

Cross-references for the same fault family, by brand:

LG H21 · LG H27

Commonly searched as: "lg h23" · "lg error code h23" · "lg air conditioner h23"

Sources

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