Why Does My Dryer Smell? Musty, Burning, or Like Mildew (and How to Fix It)

A dryer smells musty or like mildew when damp lint, leftover moisture, or a blocked vent lets mold grow. A burning smell usually means lint is overheating or a part is rubbing. Stop the dryer if it smells burnt, unplug it, then clean the lint screen, the lint trap housing, the drum, and the vent. Most smells go away once airflow is back.

Clothes should come out of a dryer smelling fresh, or at least like nothing. When your dryer starts to smell like a damp basement, a burning toaster, or something worse, it is telling you something. Some smells are just a nuisance. Others are a warning sign. This guide shows you how to tell the difference and how to fix each one.

What does your dryer smell like?

Use this list to find your smell quickly.

If it smells like burning, do this first

A burning smell is not one to ignore. Fire safety groups such as the National Fire Protection Association report that clothes dryers cause thousands of home fires every year, and failure to clean them is the leading factor. Lint is very flammable.

1. Stop the dryer and unplug it. If it is a gas dryer, close the gas valve if you know where it is.
2. Open the door and check for anything hot or melted inside, such as a lighter, a crayon, or a plastic item that got in with the clothes.
3. Take out the lint screen and look for a layer of lint, a burnt spot, or a tear.
4. Look in the lint screen slot with a flashlight. Lint can pile up in there.
5. Check the vent hose behind the dryer for kinks, crushing, or lint.
6. If everything looks clear, run the dryer for a few minutes while you stay in the room. If the smell returns, stop and call for service.

Why a dryer smells musty or like mildew

A dryer is warm and sometimes damp. That is what mold and mildew like. A musty smell usually comes from one of these:

• Wet lint. Lint that does not dry fully can grow mildew in the lint trap, the housing, or the vent.
• A blocked or long vent. If the hot, moist air cannot leave the house, it comes back into the drum.
• A vent that runs through a cold space. Moisture condenses in the pipe and drips back.
• Damp clothes sitting inside. If you leave a wet load in the dryer, or shut the door on a damp towel, mildew can start.
• Dirty drum and seal. Soap, softener, and dust build up on the drum and the door seal.
• A bad washer. If the clothes already smell when they come out of the wash, the dryer is not the cause. Read why a washing machine can smell.

Fix 1: Clean the lint screen after every load, and wash it every few months

Pull the screen out, remove the lint by hand, and then run your finger across the mesh. If the mesh looks clogged, even with no lint, there may be a film from dryer sheets and softener. Wash the screen in warm soapy water, scrub it with a soft brush, rinse, and let it dry completely before you put it back. Do this every few months.

Fix 2: Vacuum the lint trap housing

Lint falls past the screen and collects in the slot. Use a vacuum with a narrow attachment, or a lint brush made for dryers, to clean it out. You can also use a long flexible brush. Take care not to push lint further down.

Fix 3: Clean the drum and the door seal

1. Unplug the dryer.
2. Wipe the inside of the drum with a cloth dampened in warm water and a little dish soap or white vinegar.
3. Wipe the door seal and the glass, or the door gasket.
4. Run a warm cycle with a few old towels to wipe off any cleaner and dry the drum.

If you have a sticky film on the drum, it may be from dryer sheets. Use less, or switch to wool dryer balls. For a tough film, a drum cleaner made for dryers works well.

Fix 4: Clean the dryer vent

This is the fix that matters most, for both smell and safety.

1. Unplug the dryer and pull it away from the wall. Take care with a gas line.
2. Disconnect the vent hose from the back of the dryer and from the wall.
3. Clean the hose with a vacuum or a dryer vent brush kit, which has long rods that attach to a drill. Replace a hose that is crushed, torn, or made of white plastic or foil that sags.
4. Clean the duct inside the wall as far as you can reach.
5. Go outside and check the vent hood. Remove lint, birds' nests, and leaves. Make sure the flap opens freely.
6. Put it back without kinks, and keep the hose as short and straight as you can.

If your vent run is long, goes through the roof, or has many turns, hire a professional dryer vent cleaner. Many do the job for a reasonable price. A clogged vent also makes the dryer take much longer, which you can read about in a dryer that takes forever to dry.

Fix 5: Do not leave wet clothes in the dryer

If a load is done but you cannot take it out, leave the door open. If you forgot a load, rewash it before you dry it, because mildew in damp fabric needs a hot wash to clear. Do not stuff the dryer. A dryer that is too full will not dry evenly and will leave damp pockets.

Fix 6: Check for something stuck or rubbing

A hot rubber or plastic smell can come from an item that is melting, or from a belt, roller, or drum seal that is wearing. Open the dryer and look inside the drum, down the sides, and under the lip for coins, lip balm, pens, or a sock caught in the back. If the drum squeals or thumps when it runs, the belt or rollers may be worn. That calls for a repair.

Fix 7: Run a cleaning cycle

After you have cleaned the lint screen, the housing, the drum, and the vent, run the dryer empty on a high heat setting for 10 to 15 minutes. This dries any damp spots and burns off dust. If the dryer has a drum clean cycle, use it. Then wipe the drum with a dry cloth and run a small load of old towels.

What if the smell is on the clothes only?

Sometimes the dryer is clean, but clothes smell musty. That means the smell is in the fabric. Rewash the clothes with hot water if the label allows, add a cup of white vinegar to the rinse, and dry on high heat. Do not use too much detergent or softener, which can trap odors. If the smell is in all of your laundry, check the washer. For a musty smell in the room, see why a room can smell musty.

Does a gas dryer smell like gas?

Gas dryers use natural gas or propane, and you may notice a brief gas smell when the burner lights, since a little unburned gas can escape. That should fade in a few seconds. A strong, lingering, or rotten egg smell is not normal. Do not turn any switches on or off. Leave the home, and then call your gas company or 911 from outside.

How to prevent dryer smells

• Clean the lint screen after every single load.
• Clean the lint trap housing and the drum every few months.
• Have the vent cleaned at least once a year.
• Keep the vent hose short, straight, and metal.
• Do not overload the dryer.
• Take clothes out when the cycle ends, and leave the door open between loads so the drum can dry.
• Use less dryer sheet and softener, or switch to dryer balls.
• Check that the outdoor vent flap opens when the dryer runs.

When to call a professional

Call for repair or vent cleaning when:

• A burning or electrical smell comes back after you have cleaned.
• The dryer is very hot to the touch or the room feels hot.
• The drum squeals, thumps, or does not turn.
• Clothes still take more than one cycle to dry after you have cleaned the vent.
• You cannot reach the vent, or it runs through the roof or a long wall.
• The smell is gas.

Bottom line

A smelly dryer is almost always a lint or airflow problem. Clean the lint screen and the housing, wipe the drum, and clear the vent. Treat a burning smell as a safety issue first. If you do those steps and the smell stays, a part is likely worn, and a technician should look at it. For other burning smells at home, read why a house can smell like burning when the heat turns on.