No verified model list is available for this code
A manufacturer code/support source may be available, but no exact supported model has been documented for this record. Do not treat the code as a model-specific diagnosis without checking the manual.
Verify the full model number against the manufacturer manual.
Open manufacturer sourceWhat does this code mean?
LG associates CH90 with installation or test-run warning on supported air conditioners. Confirm both indoor and outdoor unit models.
Manufacturer guidance is model/type dependent. The code alone does not identify a failed part.
The exact code and primary meaning appear in manufacturer documentation. Scope: Üreticinin belirttiği cihaz türü / desteklediği model ailesi. Individual parts and all models are not verified.
Open manufacturer sourceWhat can you try?
- 01
Record the code and exact appliance model
Photograph CH90 as displayed and record the full model number from its label. LG may use different meanings for the same characters on other products.
What the result means: Do not treat a generic code as proof of a failed component.
- 02
Check whether this followed installation
If the error started immediately after installation or relocation, call the installer. Do not open inter-unit wiring or refrigerant pipes.
What the result means: An immediate post-installation error points to installation/test conditions.
- 03
Attempt one safe reset where appropriate
LG describes switching power off for approximately five minutes and restoring it for applicable units. Do not try this if there is smoke, damaged wiring or repeated breaker trips.
What the result means: If the code returns, stop repeated resets and request service.
- 04
Escalate with useful details
Give support the exact CH90 display, full model, when it appeared and safe checks completed. Do not run the unit with smoke, leakage, burning smell or breaker trips.
What the result means: A service technician must test the suspected component rather than guessing from the code.
Stop immediately for leaks, smoke, burning smell or electrical danger. For gas leaks, leave the area and call local emergency services.
How do you actually fix this?
Start with safe checks. Some codes have no safe home fix; in that case we explain what the professional repair actually involves.
Practical fixes you can try
- Turn off the AC and record whether the code began immediately after installation. Check only an accessible indoor filter.
- Do not work on outdoor wiring or refrigerant piping. Give the installer both unit model numbers if this appeared after fitting.
- Never run hidden service test modes unless the user manual explicitly authorises them.
If it persists, how is it actually repaired?
The installer verifies matched units, piping, electrical connections and commissioning checks against manufacturer requirements and corrects confirmed installation faults.
How do you know it is fixed? Commissioning checks must pass and normal operation must resume.
Safety and warranty: Warranty terms depend on manufacturer, model and local law. Damage caused by unauthorised disassembly or improper repair may be excluded. Live electrical work, gas, refrigerant circuits and sealed cabinets require qualified professionals; this is not a DIY instruction for those tasks.
Evidence: The manufacturer link above supports the broad code meaning. The repair pathway is a general technical diagnostic explanation, not a confirmed failed-part diagnosis for every model.
Manufacturer source
Independent safety-focused explanation with a manufacturer link. Possible causes are not verified part diagnoses; the code may vary by model or region.
Open original manufacturer guidance ↗