LG Dryer d90 error code
Flow Sense detected that your exhaust ductwork is about 90% blocked. This is a serious restriction. Drying will be very slow, and the fire risk is higher than with d80.
Also shown as: d90, D90
Last updated: October 6, 2026
What causes the d90 error?
- Heavy lint buildup inside the ductwork
- Crushed or kinked flexible vent hose
- Duct run too long or with too many bends
- Outside vent cap blocked by lint or a nest
- Lint filter caked with residue
How to fix LG d90 — step by step
Work through these in order, from simplest and safest first. Stop as soon as the code clears.
- Stop and clean the lint filter
Remove all lint from the filter. Wash it with soap and water if fabric softener film has built up, then dry it fully before replacing. - Check outside airflow
Run the dryer and feel the outside vent. Weak or no airflow means the blockage is severe and the duct needs cleaning before further use. - Inspect and straighten the duct
Pull the dryer out, check the hose for crushing or kinks, and make sure it is the rigid or semi-rigid metal type, not flimsy foil.Safety warning: Unplug the dryer before moving it. - Clean the entire duct run
Brush the duct from both ends with a vent cleaning kit, or call a duct cleaning service. Do not keep running the dryer until airflow is restored.Safety warning: At 90% blockage, running the dryer is dangerous and could cause a fire.
When to call a technician
- No airflow at the outside vent after cleaning
- The warning stays on after 5 or more cycles
- You smell burning
- The duct disappears into walls or the attic
Frequently asked questions
Is d90 worse than d80?
Yes. The number is the estimated blockage percentage, so d90 means roughly 90% of the airflow is blocked.
Can I run one more load before cleaning?
It is not worth the risk. Clean the vent first, since severely restricted dryers overheat.
How often should I clean the vent?
Check the outside airflow every few months and do a full duct cleaning at least once a year.
Sources
Every meaning and fix above was checked against official manufacturer documentation:
FixCode provides general troubleshooting information only — not professional repair advice. If you are unsure about any step, stop and call a qualified technician. Repairs done incorrectly can be dangerous and may void your warranty.