LG Mini-Split Code CH23
Soft lockoutShown as: Outdoor LED01 (red) blinks 2 times, LED02 (green) blinks 3 times
DC link voltage error - the DC bus inside the inverter has dropped below about 140 VDC or risen above about 420 VDC. Almost always caused by a supply-voltage problem or a failed reactor (choke) in the outdoor unit.
Manual wording: “DC Link Low Voltage (DC Link Voltage is <140VDC) / DC Link High Voltage (DC Link Voltage is >420VDC)”
Documented for: All LG residential mini-split outdoor units
Likely causes, most common first
- Input voltage error (low voltage)
- Reactor disconnection or bad fastening / reactor wire open
- PCB failure in the DC link voltage sensing section
What you can safely check yourself
- Check the breaker is fully on and not partially tripped
- Check the outdoor disconnect switch is on
- If the house has just had a brownout or power outage, turn the system off at the breaker for three minutes and back on
When to call a technician
Checking the reactor, the DC bus, or the power cable is high-voltage work on a charged inverter board. Call a technician.
A LG mini-split throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- MULTI F / MULTI F MAX Outdoor Unit Installation Manual (LG Electronics U.S.A., Inc., Multi F and Multi F MAX multi-zone heat pump outdoor units (LMU series) with standard wall-mount, Art Cool, cassette and ducted indoor units) · checked 2026-08-25
- Single Zone Four-Way Ceiling-Cassette Installation Manual (LG Electronics U.S.A., Inc., Single-zone four-way ceiling cassette indoor units with LUU090HV through LUU420HV outdoor units) · checked 2026-08-25
- Convertible Mid-Static Ducted LGRED Degree System Installation Manual (LG Electronics U.S.A., Inc., LGRED single-zone convertible mid-static ducted indoor units with LUU180HHV / LUU240HHV outdoor units) · checked 2026-08-25
- Defining Common Error Codes - Standard Wall-Mounted High-Efficiency Single Zone Systems (LG Electronics U.S.A. - Commercial Air Conditioning, LS091HSV and LS121HSV systems (LSN091HSV / LSN121HSV indoor units, LSU091HSV / LSU121HSV outdoor units)) · checked 2026-08-25
- Room Air Conditioner SVC Manual (General) - Trouble Shooting Guide with Error Code (LG Electronics, All LG single-zone room air conditioner / mini-split chassis (SW, SB, SC, S4, S5, SH, SA, SJ, SK)) · checked 2026-08-25