LG Air Conditioner Error Code CH48
Two outdoor sensors share one plug, and the board has lost both readings at once, which usually means the plug or its cable rather than two failed sensors. The unit stops until the connection is restored.
Also shown as: 48
Applies to: Residential wall-split and multi-split systems
Common causes
- Dual sensor plug disconnected
- Sensor cable damaged
- Dual sensor assembly failed
- Outdoor control board fault
What to check, in order
- Turn the unit off with the remote, then switch off its circuit breaker (or unplug it) and wait at least five minutes before switching back on.
- If the code appeared right after other work was done on the unit, say so when booking: a plug left off during service is a common cause.
- If it returns after the reset, the sensor plug and cable need professional checking.
Clear the code and test
- Fix what the checks above found first — a filter cleaned, an obstruction removed, the breaker restored. Clearing the code without fixing the cause only brings it back.
- Restore power at the breaker and switch the unit on with the remote.
- Run the unit in cooling or heating for ten to fifteen minutes and watch whether the code returns; some codes only appear after the compressor has run for a while.
- If the unit runs with no code, the fault is cleared. If the code returns, write down the code and whether the indoor or outdoor unit shows it before calling a technician — it speeds up the diagnosis.
When to call a professional
This code usually points to a faulty part, wiring or the control board on a LG air conditioner. Run the checks above to rule out the simple causes, then book a technician — and book one straight away if any of these apply:
- The code comes back after you have run the checks and a test cycle.
- You smell burning, see sparks or scorch marks, or the breaker trips.
- Water is leaking and you cannot stop it.
- The fix needs panels opened beyond what your manual describes, or a part tested with a meter, and you are not set up for that.
When you call, give the brand, the code CH48, your model number (on a label on the side of the indoor unit) and the checks you already ran. It shortens the visit.
Repair or replace?
This fault is in professional territory: the fix usually means a major part or board-level work, and the labour adds up. If your machine is already well into its service life, get the repair quote first, then compare it with the price of a current equivalent model before you decide. Paying a large share of a new machine's price to repair an old one is rarely the better deal; replacing a machine over one cheap fault is wasteful too.
Parts that may be involved
Dual discharge/air temperature sensorOutdoor control board
Parts are model-specific. Find your model number first — usually on a label on the side of the indoor unit — and match the part to that number before ordering.
Questions people ask about CH48
What does CH48 mean on a LG air conditioner?
CH48 means: Outdoor discharge pipe and air sensors disconnected. Two outdoor sensors share one plug, and the board has lost both readings at once, which usually means the plug or its cable rather than two failed sensors. The unit stops until the connection is restored.
Can I fix LG CH48 myself?
Only the preliminary checks. Code CH48 usually means a part, wiring or the control board has failed, which is a technician job. Run the checks to rule out simple causes before you book.
How do I clear LG CH48?
Fix what the checks above found first — a filter cleaned, an obstruction removed, the breaker restored. Clearing the code without fixing the cause only brings it back. Restore power at the breaker and switch the unit on with the remote. Run the unit in cooling or heating for ten to fifteen minutes and watch whether the code returns; some codes only appear after the compressor has run for a while.
Sources checked
The meaning and checks for this code were checked against the sources above in November 2026. Codes vary by model and region; if your manual lists a different meaning for your exact model, follow the manual.