LG Mini-Split: 7 Flashes
A LG mini-split LED pattern starting with 7 flashes matches 3 documented codes: CH07, CH72, CH73. Watch the full pattern (short vs. long flashes) to tell them apart — all 3 are explained below.
Code CH07: Different mode operation error
Different mode operation error. On a multi-zone system, one indoor unit is calling for heating while another on the same outdoor unit is calling for cooling or dry. One outdoor unit can only do one thing at a time, so the conflicting zones are blocked. LG's consumer page describes it as the units being set to different operating modes.
Manual wording: “07 Different mode operation error”
Documented for: LG Multi F / Multi F MAX multi-zone systems (LMU outdoor units with two or more indoor units)
Likely causes, most common first
- One indoor unit set to heating while another indoor unit on the same outdoor unit is set to cooling or dehumidify
- A zone left running in a stale mode from a previous season
What you can safely check yourself
- Set every indoor unit connected to the same outdoor unit to the same mode - all cooling/dry, or all heating
- Turn off any indoor unit that does not need to run
- After all zones agree on a mode, the code should clear on its own
When to call a technician
If every indoor unit is already in the same mode and CH07 keeps coming back, one indoor unit is sending a bad mode signal and needs 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
- LG Air Conditioner - Guide to Error Codes (LG USA Support help library) (LG Electronics U.S.A., Inc., LG residential single-split and multi-split air conditioners / heat pumps) · checked 2026-08-25
Code CH72: Four-way
Four-way (reversing) valve switching failure. The valve that flips the system between heating and cooling did not change over when commanded, so the unit cannot switch modes.
Manual wording: “Switching for 4 way valve is failed”
Documented for: LG single-zone room air conditioner / mini-split heat pump outdoor units
Likely causes, most common first
- Indoor or outdoor pipe sensor short or open
- Disconnection of the 4-way valve connector
- 4-way valve coil open or short
- Burned part inside the PCB (4-way valve output)
What you can safely check yourself
- Turn the system off at the breaker for three minutes and back on, then try the mode change again
When to call a technician
The reversing valve and its coil are on the refrigerant circuit inside the outdoor unit. A technician has to measure the coil resistance and the board's output before deciding what to replace.
A LG mini-split throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Source
- 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
Code CH73: PSC / PFC overcurrent error detected in software - the outdoor unit's power factor correction stage saw a current peak beyond its limit
PSC / PFC overcurrent error detected in software - the outdoor unit's power factor correction stage saw a current peak beyond its limit. Same protection as CH27 but caught by the firmware rather than the hardware trip.
Manual wording: “PSC / PFC overcurrent error (SW)”
Documented for: All LG residential mini-split outdoor units
Likely causes, most common first
- Overload operation - outdoor fan restricted, screened, or blocked
- Bad reactor fastening
- Burned PCB internal parts (PSC module)
What you can safely check yourself
- Clear leaves, grass clippings, snow, or debris away from the outdoor coil and fan
- Check and clean the indoor air filters
- Turn the system off at the breaker for three minutes and back on
When to call a technician
The PFC stage and reactor are inside the live inverter section of the outdoor unit. 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
- 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
- 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