To clean a dryer vent, unplug the dryer, pull it away from the wall, disconnect the duct and brush the lint out of the duct, the dryer outlet and the wall pipe, then clear the outside vent cap. Reconnect everything and run the dryer to confirm air blows out strongly outdoors.
Signs the vent is clogged before you start
A blocked vent rarely announces itself with smoke. The early clues are quieter, and the U.S. Consumer Product Safety Commission names the main one: clothes that are still damp at the end of a normal cycle, or loads that need longer than usual to dry, can mean the lint screen or exhaust duct is blocked.
- The laundry room feels unusually warm or humid while the dryer runs.
- The top of the dryer or the clothes feel hotter than they used to.
- You smell something scorched or dusty during a cycle.
- The flap on the outside vent stays shut, or barely moves, when the dryer is on.
- Lint collects around the outdoor cap or behind the machine.
If the dryer isn’t heating at all, the vent is still the first place to look, though a heating fault can also be to blame.
Tools for a dryer vent cleaning job
You don’t need much. A dryer vent brush kit with flexible rods that screw together lets you reach several feet into the duct. A vacuum with a hose attachment picks up what the brush loosens. Add a screwdriver or nut driver for the duct clamps, foil tape rated for ducts if your clamps are worn, work gloves and a flashlight.
A leaf blower is sometimes used to push debris out from the inside, but only do that with the outside cap open and nothing blocking it.
Cleaning the vent step by step
- Unplug an electric dryer. For a gas dryer, turn the gas valve off and move the machine gently so the gas line isn’t kinked or strained.
- Slide the dryer out and loosen the clamp holding the duct to the dryer outlet.
- Vacuum the outlet on the back of the dryer and the lint that has gathered on the floor.
- Feed the brush into the duct and the wall pipe, twisting as you push, then pull it back and vacuum the lint it drags out.
- Go outside, remove or open the vent cap, and pull out lint, nests or debris by hand or with the brush.
- Reconnect the duct, press the dryer back without crushing it, restore power or gas, and run an air-only cycle while you check the outdoor flap.
The lint screen deserves attention too. Clean it before or after every load, and wash it with warm soapy water now and then if fabric softener leaves a film that water beads on.
Replace foil or plastic ducts while the dryer is pulled out
If the duct behind your dryer is white vinyl or thin crinkly foil, this is the moment to swap it. The CPSC safety alert on overheated dryers recommends replacing plastic or foil accordion ducting with rigid or corrugated semi-rigid metal duct, since the flexible kinds trap lint more easily and crush or kink, which cuts airflow. Keep the run as short as the room allows, with as few bends as you can manage, and check your dryer’s manual for its maximum duct length.
How often to clean it, and when to call a pro
The CPSC says to clean the vent and exhaust duct periodically and to check the outside vent while the dryer runs. A yearly cleaning is a common habit, but homes with big families, pets or long duct runs may need it more often. Let the warning signs above set your schedule.
Call a dryer vent service if the duct runs through an attic, a ceiling or up to the roof, if you can’t reach the blockage, or if the pipe is disconnected inside a wall. Hire a qualified technician to clean lint from inside the dryer cabinet as well, which the CPSC also recommends doing periodically.
Frequently asked questions
Can I clean a dryer vent with a leaf blower?
Some people blow lint out from the inside with a leaf blower, but it only works when the outdoor cap is open and clear, or the debris just packs tighter. Brush the duct first so the air has something loose to push. Wear eye protection outside, since lint and dust will fly.
Why does my dryer still take long after cleaning the vent?
Check that the duct behind the dryer didn't get crushed when you pushed the machine back, and confirm the outdoor flap opens during a cycle. A lint screen coated with softener film also slows drying. If airflow is strong and loads are still slow, have a technician check the heating parts.
Is it safe to use a dryer without the lint screen?
No. Running the dryer without the lint filter lets lint flow directly into the duct and around the machine, which is exactly what fire safety agencies warn against. Replace a torn or missing screen with the correct part for your model before drying another load.
How long can a dryer vent be?
Under the International Residential Code, the exhaust duct can run up to 35 feet from the dryer's transition hose to the outside, and fittings shorten that. Each standard mitered 90 degree elbow counts as 5 feet and each 45 degree elbow as 2.5 feet. The code also lets the dryer maker's installation instructions set the limit.
How do I install a dryer vent hose?
Use a single length of listed rigid or semi-rigid metal transition duct no longer than 8 feet, never plastic or foil. Slide one end over the dryer's exhaust outlet and the other over the wall pipe, then tighten a clamp at each joint rather than using screws, which can poke into the duct. Keep it short and uncrushed.
