LG mini split error code CH24
High or low pressure switch operated. Also shown as CH 24, CH24.
- TypeProtection
- SystemRefrigerant circuit
- Can I fix it?Homeowner checks, then maybe a tech
What CH24 means on a LG
A pressure switch opened: head pressure too high or suction pressure too low.
On this platform, CH24 is a protection: the system stopped or throttled itself to prevent damage; many clear on their own once conditions return to normal.
Common causes
- High side: dirty outdoor coil, failed fan, overcharge.
- Low side: low charge, closed service valve, restriction, frozen indoor coil.
How to fix it yourself
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician.
- Look at the outdoor unit: clear leaves, cottonwood fluff, snow or ice from the coil and make sure the fan can spin freely and nothing is stacked against the cabinet.
- Confirm both service valves are fully open.
- Pull the front panel and check the filters and the indoor coil. Dirty filters and a matted coil restrict airflow, and airflow problems trigger a surprising number of protection codes.
- Anything inside the refrigerant circuit (sensors are fine, but valves, compressors and leaks are not) needs EPA-certified refrigerant handling. That is a technician job.
Switch off power at the breaker before opening either unit. Capacitors in the outdoor unit hold a charge for several minutes after power is cut.
When to call a technician
A technician needs gauges to tell which side tripped.
Which LG units show CH24
This page applies to LG Art Cool, Standard, Mega and Multi F units. LG's own documentation lists CH24 as "High or low pressure switch operated", the same definition used across the LG it is built on. If your unit shows a code with a different shape (for example a four-character code, or a plain number), it is from a different table; use the lookup with your exact code.
Where LG shows this code
The indoor display shows CH followed by a number (CH05, CH38). Units without a display blink the indicator lamps in a pattern; the outdoor board LEDs blink the same number. If someone tells you 'CH 5', that is CH05. CH01 to CH12 are indoor-unit faults, CH21 to CH29 are inverter and compressor faults, CH32 to CH38 are refrigerant-side protections, CH40 to CH48 are outdoor sensors, and CH51 to CH73 are outdoor-unit system faults.
Other LG codes
Same part of the system as CH24:
Questions people ask
Can I reset a LG CH24 code myself?
Yes. Turn the system off at the breaker for five minutes, then restart it. If CH24 comes back, the fault is real and needs the checks above.
Is it safe to keep running a LG showing CH24?
Not repeatedly. A protection code means the unit stopped itself to prevent damage, and resetting it over and over can turn a cheap repair into a compressor failure. Reset once, check the basics, and stop if it returns.
Do I need a technician for LG CH24?
Work through the checks below first; they resolve most cases. If they do not, the repair itself may need a technician. A technician needs gauges to tell which side tripped.
Sources
- LG residential split service manuals (error code tables)
Updated September 2026. Codes and definitions vary by model year. If your manual disagrees with this page, your manual wins. Send a correction.