LG Dryer d90 — What It Means & How to Fix It

Also shown as d95 on some models.

By Callum Griffin · Researched and verified against manufacturer and repair documentation · Reviewed June 2026

d90 — and the more severe d95 — is LG's Flow Sense system reacting to a badly blocked exhaust of 90% or more by cooling the dryer down and stopping the cycle, so unlike the milder d80 you have to clear the vent before it will run properly again.

What this code means

When Flow Sense measures airflow at 90% or worse restriction it logs d90, or d95 if the duct is 95%+ choked, and deliberately halts heating so trapped heat and lint can't become a hazard. It's the same duct-blockage problem as d80, just far enough along that the dryer refuses to soldier on. Loads are left damp mid-cycle until the exhaust path is opened up.

d90 and d95 sit at the top of the same Flow Sense scale, differing only in how choked the duct is — 90% versus 95%+ — and both call for the identical vent cleaning. If a fully cleared vent still throws the code, the airflow sensor or control reading is worth a technician's look.

Most likely causes

CauseHow likelyDIY-fixable?
Heavy lint blockage deep in the wall duct or at the outdoor vent Very common Yes — no tools
Collapsed, crushed, or disconnected transition hose Common Yes — no tools
Outdoor vent flap jammed shut by lint, snow, or a nest Common Yes — no tools
Extremely long or multi-elbow duct run Occasional Partly — inspect only
Faulty Flow Sense airflow sensor reading a blockage that isn't there Less common No — technician job

What you can try yourself

  1. Unplug the dryer and start at the lint screen — clean it and rinse off any softener-sheet residue — then work outward along the exhaust path.
  2. Pull the transition hose off the back and clear it; look for a section crushed flat behind the machine or a joint that has pulled apart.
  3. Run a vent brush through the wall duct as far as it reaches, then go outside and check the exterior flap opens fully when the dryer blows — clear any lint mat, debris, or nest.
  4. Reconnect, restore power, and start a short cycle; with the vent clear the dryer should heat and run to completion instead of cooling down and stopping.
  5. If d90 or d95 returns with a verified-clear vent, stop and book a technician — the Flow Sense sensor or control board may be misreading airflow.

When to call a technician

Typical professional repair cost: Vent cleaning runs about $100–$200; if the vent is clear, a Flow Sense airflow sensor or control repair typically costs $150–$300 with labor.

Frequently asked questions

How do I fix a d90 code on my LG dryer?

Clear the exhaust from end to end: the lint filter, the transition hose, the wall duct, and the outdoor flap. d90 means 90%+ blockage, so the dryer won't run normally until air can escape freely. After cleaning, run a short cycle to confirm it heats and finishes instead of cooling down and stopping.

What's the difference between d90 and d95 on an LG dryer?

Both mean a severely blocked vent that makes the dryer cool down and stop; d90 is roughly 90% restricted and d95 is 95% or more. The fix is identical — a thorough vent cleaning from the lint filter to the outdoor vent. The higher number just means even less air is getting through.

Why does my LG dryer stop and show d90 partway through a cycle?

Flow Sense detected that the exhaust is badly blocked and shut the heat off mid-cycle to prevent overheating. It's a safety response, not a random glitch. Clear the entire vent line and the dryer will run through a full cycle again.

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