The short answer
Clothes still damp after a full cycle almost always means restricted airflow: a loaded lint filter, a blocked or crushed duct, or a vent hood that no longer opens. Heat faults exist, but a dryer that is warm and slow is an airflow problem until proven otherwise.
What you observe
- Loads need two cycles where one used to do — The signature of a gradually restricting duct.
- The laundry room becomes hot and humid during a cycle — Air is leaving the duct into the room instead of outside.
- Clothes are hot but still damp — Heat without airflow.
- Lint appears around the door or behind the machine — The duct is not carrying it away.
- Only heavy items stay damp — Overloading, or a load mixed too widely.
- Not this fault: the drum turns and nothing gets warm at all — That is the not-heating page.
Ranked for any vented dryer
- Lint filter loaded, or fabric-softener film blocking its mesh — First, and the film is invisible until the filter is rinsed.
- Duct blocked, crushed or too long with too many bends — Second, and the usual cause of a gradual decline.
- Vent hood flap stuck closed or blocked by a nest — Third, and it is outside where nobody looks.
- Overloading — Fourth: air cannot pass through a packed drum.
- Moisture sensor fooled by fabric-softener residue — Fifth, and it ends cycles early on auto settings.
- Heating fault producing only partial heat — Last, and it usually shows as no heat rather than weak drying.
Work through it in this order
- Clean the lint filter and rinse it under water — A film that water beads on is a blocked filter that looks clean.
- Disconnect the duct and run a short cycle — Fast drying with the duct off proves the duct is the problem.
- Go outside and watch the vent hood while the dryer runs — Weak or no airflow at the hood confirms it.
- Only then consider the moisture sensor and the heat — The air path comes first every time.
Owner-side checks
- Clean the lint filter every cycle and rinse it monthly — Softener film blocks a filter that looks perfectly clear.
Tools: soft brushAbout 10 min
- Pull the machine out and disconnect the duct, then run a timed cycle — If drying is normal without the duct, the duct is the fault.
About 30 min
- Clean the duct from both ends — A long flexible duct behind a machine is where most lint collects.
Tools: duct brush, vacuumAbout 45 min
- Check the outside vent hood opens fully and is not nested — Birds and lint both block hoods completely.
Tools: torchAbout 20 min
- Dry a smaller load as a test — Overloading produces exactly this complaint.
About 45 min
- Stop before opening the cabinet to reach the blower or heat source — Lint, mains voltage and, on gas models, a burner all live in there.
Lint is the hazard here
Safety
Unplug the appliance or switch off its breaker before removing any panel. A capacitor can hold a charge after the power is off. A restricted dryer runs hotter than it should, and lint is combustible: a duct that has never been cleaned is a fire risk as well as a drying problem. Never use plastic or foil concertina ducting where a rigid or semi-rigid metal duct is specified, and never vent a dryer into the room.
When to call
Call when the machine dries normally with the duct disconnected but the duct run cannot be cleared, because that is a duct-replacement job rather than an appliance repair. Call an appliance technician when airflow is good and drying is still poor, which points at the moisture sensor or partial heating. Call at once if you smell burning during a cycle: with lint in the system that is urgent.
Related pages
What is out of scope
Generalized across the dryer families under this badge and across fuel types; where a family-specific or model-specific page exists it is the narrower answer. Not here: duct length and diameter specifications, sensor values, airflow figures and the differences between vented, condenser and heat-pump machines.
Lead Appliance Repair Technician · 12 years experience
Experienced technician with 12 years specializing in washing machine and dryer repairs across all major brands.
