What CH66, CH90, CH91, CH92, CH93 Means
CH66, CH90, CH91, CH92, and CH93 together indicate an installation or test-run problem, per LG's combined troubleshooting article - incorrect wiring, an incomplete test run after installation, or restricted refrigerant flow during the test run.
Common Causes of CH66, CH90, CH91, CH92, CH93
- Incorrect wiring from installation
- Incomplete test run after installation
- Restricted refrigerant flow during the test run
🔧 One Safe Check You Can Try
Because this group is specifically tied to installation, LG's guidance is to contact your installer directly rather than troubleshoot it as a standalone appliance fault.
⚠ Why You Shouldn't Go Further Than That
- This is explicitly an installation-stage fault group in LG's own documentation - working through it without involving the original installer risks missing a wiring or refrigerant-charge issue that needs correcting at the source.
- Never disassemble the unit yourself to investigate wiring or refrigerant connections - that carries the same fire and shock risk LG warns about for every code in this family.
Opening a panel to inspect or repair something yourself doesn't automatically cancel your manufacturer's warranty — but it can risk accidental damage, and some manufacturers do have specific service conditions. Check your product's warranty terms, or ask us, before deciding.