LG Dryer Error Code d75 — Exhaust Duct 75% Blocked
What this means
The d75 error code on LG dryers indicates that the FlowSense system has detected approximately 75% blockage in the exhaust duct. LG's FlowSense technology monitors airflow through the vent system and alerts you when lint buildup restricts the exhaust. At 75% blockage, drying times are significantly increased and the dryer may overheat. If left unaddressed, blockage will worsen to d80, d90, or d95 levels, increasing fire risk. This is an early warning — address it promptly to prevent a complete blockage. The d75 code can appear on vented LG dryers, WashTower dryer units, and some ventless heat pump models.
Alternate codes: D75
Step-by-step fix
4 stepsClean the lint filter
Remove the lint filter and clean it thoroughly. Wash it with warm soapy water to remove dryer sheet residue that can coat the mesh and restrict airflow, even when visually clean. Let it dry completely before reinstalling.
Hold the filter under running water — if water pools on the surface instead of flowing through, a residue film is restricting airflow.
Disconnect and clean the exhaust duct
Pull the dryer away from the wall. Disconnect the exhaust duct from the back of the dryer. Use a dryer vent cleaning brush kit to clean inside the duct from both ends — the dryer connection and the exterior vent cap. Remove all accumulated lint.
For ducts longer than 10 feet, a rotary brush kit attached to a drill provides the most thorough cleaning.
Check the exterior vent cap
Go outside and locate the dryer vent exhaust cap. Make sure the flap opens freely and is not blocked by lint, debris, ice, or a bird's nest. Clean the cap and the last few inches of ductwork.
The exterior cap should swing open easily when you push it. If it is stuck closed, it is a major source of blockage.
Inspect for duct damage
Examine the entire exhaust duct for kinks, crushes, or sags. Replace any flexible foil duct with rigid or semi-rigid aluminum duct, which resists lint buildup much better. Reconnect all joints securely with foil tape (never use screws inside the duct — they catch lint).
Reduce the total duct length and number of elbows when possible. Each 90-degree elbow adds the equivalent of 5 feet of straight duct to airflow resistance.
When to call a professional
If you cannot access the full length of the duct (e.g., it runs through walls or the attic), hire a professional dryer vent cleaning service. Also call a pro if the d75 code returns shortly after cleaning.
Related error codes
The dryer vent is approximately 80% blocked, severely restricting airflow.
Advanced Fix · 30–90 minutes
The dryer vent is approximately 90% blocked, creating a serious fire hazard.
Advanced Fix · 30–90 minutes
The dryer vent is nearly completely blocked — extreme fire hazard.
Professional Repair · 60–120 minutes
Information compiled from manufacturer service manuals, official troubleshooting documentation, and appliance repair industry resources. This guide is for informational purposes only — always consult a qualified technician for complex repairs.
Learn more about our sourcesParts you may need
Dryer Vent Cleaning Brush Kit
Part #N/A (universal) · $20–$40
Essential tool for cleaning the exhaust duct
Rigid Aluminum Duct (4-inch)
Part #N/A (universal) · $10–$25 per section
If replacing damaged or flexible foil duct
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