What causes LG Mini Split CH38?

Not enough refrigerant after installation or relocation, for example a line set that wasn't charged for its length or a refrigerant loss during the install. LG says a technician must check the charge in this case. A refrigerant leak at a flare joint, line-set connection or coil, which LG's US page says often traces back to a loose connection made during installation. A temporary power or electrical instability that tripped the protection, which LG names as a possible cause when the code appears after a period of normal use. A fault in the outdoor unit's compressor, drive, protection circuit or electronics, which LG's US page lists among the reasons for the CH32 to CH38 group.

How do I fix LG Mini Split CH38?

Note when the code first appeared: shortly after installation or a move, or after the unit had been running fine for a while. LG's fix depends on which. If it appeared soon after installation or relocation, contact the installer. Their contact details are often on the business card they left or a sticker on the side of the unit. If it appeared during normal use, unplug the unit or switch off its circuit breaker, wait about 5 minutes, then restore power and restart. If CH38 comes back after the power reset, stop using the air conditioner and request LG service or a qualified HVAC technician.

When should I call a pro for LG Mini Split CH38?

CH38 returns after a 5-minute power reset. LG says to stop using the unit and have a qualified technician inspect it. The code showed up after installation or relocation. LG says the installer or technician must check whether the system has enough refrigerant and inspect the piping connections. Any leak test, repair or recharge. This requires refrigerant handling equipment and certification, and LG warns not to charge a different refrigerant from the one on the unit's label.

Code: CH38🔧 LG Mini Split

LG Mini Split CH38 Error Code: Low Refrigerant or Refrigerant Leak (Meaning, Causes, Fixes)

Q: What does LG Mini Split CH38 mean?

CH38 on an LG mini split or ductless air conditioner means the unit has detected a low refrigerant (gas) level and stopped to protect itself. If it showed up right after installation or a move, call the installer to check the piping and refrigerant charge. If it appeared after normal use, cut power for about 5 minutes and restart; if CH38 comes back, stop using the unit and book an LG-qualified technician, since finding a leak and recharging refrigerant is not a DIY job. LG's support pages call CH38 an inspection code that "will appear when the refrigerant (gas) level of the appliance is low, to protect the appliance." LG's India error-code guide pairs it with F4 on models that use that display. In LG's owner's manuals for standard inverter outdoor units such as the UTN24R and UTN48R, code 38 is listed as "Refrigerant Leakage Error" with the state "Stop," meaning the outdoor unit shuts down rather than running on. LG's US help page groups CH38 with CH32, CH33 and CH36 as refrigerant or compressor-related codes. CH38 is different from CH35 (outdoor low pressure error) and CH32/CH33 (discharge pipe overheating), which appear in the same LG tables.

Reviewed 2026-10-24 · Based on 5 manufacturer & service sources

What the code means

LG's support pages call CH38 an inspection code that "will appear when the refrigerant (gas) level of the appliance is low, to protect the appliance." LG's India error-code guide pairs it with F4 on models that use that display. In LG's owner's manuals for standard inverter outdoor units such as the UTN24R and UTN48R, code 38 is listed as "Refrigerant Leakage Error" with the state "Stop," meaning the outdoor unit shuts down rather than running on. LG's US help page groups CH38 with CH32, CH33 and CH36 as refrigerant or compressor-related codes. CH38 is different from CH35 (outdoor low pressure error) and CH32/CH33 (discharge pipe overheating), which appear in the same LG tables.

Likely causes

Not enough refrigerant after installation or relocation, for example a line set that wasn't charged for its length or a refrigerant loss during the install. LG says a technician must check the charge in this case.
A refrigerant leak at a flare joint, line-set connection or coil, which LG's US page says often traces back to a loose connection made during installation.
A temporary power or electrical instability that tripped the protection, which LG names as a possible cause when the code appears after a period of normal use.
A fault in the outdoor unit's compressor, drive, protection circuit or electronics, which LG's US page lists among the reasons for the CH32 to CH38 group.

Safe DIY checks

⚠ Before you start

Don't open the indoor or outdoor unit or replace internal parts yourself; LG warns this can cause fire, electric shock, serious injury or death. Never try to top up refrigerant from a DIY can or with a different refrigerant type. If you suspect refrigerant has leaked into a small room, ventilate it before running the unit, as LG's service manual advises.

Note when the code first appeared: shortly after installation or a move, or after the unit had been running fine for a while. LG's fix depends on which.
If it appeared soon after installation or relocation, contact the installer. Their contact details are often on the business card they left or a sticker on the side of the unit.
If it appeared during normal use, unplug the unit or switch off its circuit breaker, wait about 5 minutes, then restore power and restart.
If CH38 comes back after the power reset, stop using the air conditioner and request LG service or a qualified HVAC technician.

🛠 When to call a pro

CH38 returns after a 5-minute power reset. LG says to stop using the unit and have a qualified technician inspect it.
The code showed up after installation or relocation. LG says the installer or technician must check whether the system has enough refrigerant and inspect the piping connections.
Any leak test, repair or recharge. This requires refrigerant handling equipment and certification, and LG warns not to charge a different refrigerant from the one on the unit's label.

Parts that commonly fix it

Always match the part number to your exact model.

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Refrigerant leak detector

Used by a technician to pinpoint where refrigerant is escaping before the system is repaired and recharged.

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Mini split line set and flare fittings

Only if the technician finds a damaged line set or a leaking flare; match the pipe sizes for your LG model.