Short answer
A dryer that needs two cycles and leaves clothes hot is almost always a blocked vent, not a failed dryer. Lint packs the exterior hood and the last few feet of duct first, so look at the flap outside before anyone sells you a part. Clear the duct end to end and most dryers dry on one cycle again. If the airflow at the hood is strong and the clothes are still hot and damp, the fault is inside the dryer.
Tell a blocked vent from a failing dryer in 10 minutes
- Start the dryer on a timed heat cycle, then go outside to the vent hood.
- Hold your hand in front of the hood. Strong warm air that pushes the flap open means the duct is clear. Weak air, or a flap that never opens, means it is blocked.
- Look at the hood itself. Lint matted around a plastic cage guard, a louver stuffed with nesting material, or a missing cover are blockages you can see from the ground.
- Pull the dryer out and disconnect the duct at the back. Pull out the lint you can reach by hand.
- Run the dryer for 1 minute with the duct off. Strong air out of the back means the dryer is healthy and the duct is the problem.
- Count the run. Measure the feet of duct between the dryer and the hood and count the elbows.
If airflow at the hood is weak, the vent is blocked and cleaning is the fix. If airflow is strong and clothes still take two cycles, stop testing the vent and have the dryer itself looked at.
Repair or replace
| Situation | What to do |
|---|---|
| Lint packed at the hood, duct run under 25 feet | Clean the duct from both ends. Most dryers dry on one cycle again the same day. |
| Run over 25 feet, or four or more elbows | Clean it, then shorten or reroute the run. A long run reclogs every year even behind a healthy dryer. |
| Ribbed foil or plastic duct behind the dryer | Replace that section with rigid metal. Ribbed duct catches lint and crushes flat behind the dryer. |
| Exterior cover broken, missing or full of nesting material | Replace it with a hooded metal cover. Clear the nest first, and check for live birds or eggs before anything goes into the duct. |
| Hood airflow strong, clothes still hot and damp | Repair the dryer. Hire an appliance tech to check the blower wheel, the thermostat and the heating element. |
| Gas dryer with weak airflow at the hood | Stop using the dryer and hire a pro. A blocked gas dryer vent can push carbon monoxide into the house. |
What it costs
Runhome contractor estimates for cleaning a two-story dryer vent from inside and outside and replacing two exterior vent covers ran from $230 to $465 as of October 2026, including the trip and assessment.
| Option | Range |
|---|---|
| Clean the dryer vent inside and out, plus replace two exterior vent covers on the same visit | $230 to $465 |
Can I do it myself?
Yes, if the vent comes out of a wall you can reach from the ground on a short ladder and the dryer runs on electricity. Buy a rotary brush kit that reaches the full length of your duct, work it in from the hood and again from behind the dryer, and vacuum both ends. Budget 2 hours the first time.
Hire for this if the hood sits above the first floor, because a 20 foot gable wall needs a 24 to 28 foot ladder and both hands. Hire for this if you have a gas dryer, because a gas dryer that vents badly can spill carbon monoxide. Hire for this if the duct runs inside a wall or a ceiling, or if you find a nest in it.
What a contractor will ask you
Have these ready and you skip the back-and-forth.
- How many stories up the vent sits, and which wall it comes out of.
- Which floor the dryer is on, including whether the laundry is in a basement or a split level.
- Whether other vents sit within a few feet of the dryer vent, so one ladder setup covers them.
- What is directly under the vent outside: flat ground, a deck, a porch roof or a slope.
- The duct size and type where it meets the wall, usually 4-inch round metal or flex.
- Whether you want the dryer pulled out and cleaned from inside as well as from the exterior wall.
- Roughly how long the duct run is and how many elbows it has.
- A wide photo of that wall taken from the ground, showing the vent.
Common questions
- Why do my clothes come out very hot but still damp?
The heat is working and the wet air has nowhere to go. A blocked duct traps humid air in the drum, so the load bakes instead of drying. Clear the duct before replacing any parts.
- How often does a dryer vent need cleaning?
Once a year for a normal run, and twice a year for a run over 25 feet or one with several elbows. Clean it sooner if drying times start to creep up.
- Is a clogged dryer vent dangerous?
Yes. Packed lint is fuel sitting next to a heat source, and it is a common cause of house fires. A blocked gas dryer vent can also push carbon monoxide back into the house.
- Birds destroyed the cover on my vent, so what now?
Replace it with a hooded metal cover and have the duct checked for nesting material. Check for live birds or eggs before anything is pushed into the duct. An open duct opening lets animals back in within weeks.
- Can I just clean the vent from outside?
Only as a stopgap. Most of the lint sits at the hood and in the last few feet, but the section behind the dryer packs up as well. A proper cleaning works the duct from both ends.