Reviewed diagnostic family

LG dryer F0 / FO / Insert Filter: lint filter missing or not seated

LG says F0/FO or a flashing Insert Filter message means the lint filter should be checked for proper installation.

LGDryerReviewed 2026-09-11

What this guide covers

Error codes: F0, FO, Insert Filter

This guide follows a structured decision tree built from manufacturer troubleshooting information. It does not assume that the most commonly replaced part is the failed part, and it does not show an exact-fit replacement part unless model compatibility has been independently verified.

Continue this exact diagnostic

Safe troubleshooting sequence

This reviewed path begins with a direct owner-safe action or status check rather than a branching question. Follow the step below, then use the interactive diagnostic if the condition persists.

  1. Power the dryer offRemove the lint filter.
  2. Clean it and reinstall it fully in its housingDo not run the dryer without the filter.
  3. Retry onceIf the message continues with the filter seated, continue.

Reviewed outcomes

Remove and reinstall the lint filter

The dryer expects the filter to be correctly seated before operation.

Evidence strength: Strong

The filter message remains with the filter installed

A persistent filter-detection condition may require service.

Evidence strength: Strong

When professional diagnosis is the safer next step

A persistent filter-detection condition may require service.

Appliance Verdict stops before energized electrical testing, gas-system work, sealed-system work, and other checks that can create unnecessary risk. A technician can use the model, issue, and completed checks from the interactive diagnostic as a starting point.

Repair or replace?

A diagnosis and a repair decision are different questions. Once you have a real repair quote, compare the total repair cost with the all-in price of a comparable replacement. Warranty or protection-plan coverage, appliance age, reliability history, efficiency, and likely future repairs can all matter. Appliance Verdict’s interactive result includes a transparent cost comparison rather than a black-box replacement recommendation.

Manufacturer sources

LG Support

Dataset reviewed through 2026-09-11. Appliance Verdict is independent and is not endorsed by the manufacturers cited. Always follow the exact owner or service documentation for your model.

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