Why does my tumble dryer smell?

A dryer smell is unusual among appliance smells because it transfers directly onto everything you own. It is also worth diagnosing carefully rather than masking, because the three families of cause are genuinely different: one is water sitting where it should not, one is product residue, and one is heat. Only the third is urgent, but it is the one to rule out first.

Safety

What you'll need

• Warm soapy water and cloths
• A vacuum with a crevice tool
• White vinegar (optional)
• A bowl for the condenser unit (optional)

Step by step

1. First, decide which of the three smells it is.Damp, musty, sour or like a wet cellar. Or chemical, waxy, perfumed or plastic. Or hot, acrid, burning or like scorched fabric. The third one ends this guide immediately.
2. If it is a burning or hot smell, stop.Switch off at the socket and do not run the machine again. A hot smell from a dryer means restricted airflow, overheating lint or an electrical fault, and it needs looking at before the next cycle rather than after it.
3. For a damp smell, start with the water container.Empty it, wash it in hot soapy water, and check the compartment it sits in. Water left standing in a warm tank grows exactly what you are smelling. Empty it every load from now on.
4. Remove and rinse the condenser unit thoroughly.On a condenser machine, behind the flap at the bottom front. Rinse from both sides until the water runs clear. Lint trapped in wet condenser fins is a common source of a musty smell and it is not visible from outside.
5. Clean the filter and the housing beneath it.Wash the filter in warm soapy water to remove the conditioner film. Then unplug the machine and vacuum the recess beneath, where damp lint mats and sits.
6. Check the door seal and the drum lip.Fold the seal back and wipe underneath it. Damp lint accumulates in the gap between the drum and the door frame and stays wet between cycles.
7. Check whether the load is going in too wet.Washing that sat damp in the machine overnight before drying is already sour, and the dryer bakes that smell into the fabric and into itself. The problem may be upstream.
8. For a chemical or waxy smell, stop the dryer sheets.Dryer sheets deposit a coating on the drum, the filter and the sensor bars, which then bakes on each cycle. Wipe the drum with a cloth wrung out in warm water with a little white vinegar, and wash the filter properly.
9. Wipe the moisture sensor bars.The metal strips in the drum or filter housing. Conditioner and sheet residue coats them, which also makes the machine over-run. A cloth and a little white vinegar clears it.
10. Run an empty cycle to clear it.After cleaning, a short empty warm cycle with the door open afterwards dries everything out and vents the residual smell rather than sealing it in.
11. Leave the door ajar between uses.The same habit that keeps a washing machine sweet. A warm damp drum sealed shut is where the musty smell comes back from.
12. Check the vent hose if the machine is vented.A hose with a low point holds condensate, and a hose whose outside flap does not close lets damp air and outside smells back in. Both produce a smell that only appears when the machine runs.

Tips

• A dryer that smells of the last thing you dried in it usually has residue on the drum rather than a fault. Wipe the drum out with a damp cloth between very different loads.
• Never put anything scented, oily or aerosol into a dryer drum to mask a smell. Oil and heat in a tumbling drum is precisely the combination to avoid.
• If the smell only appears in a particular room or only in winter, consider whether it is actually the room's ventilation rather than the machine — a condenser dryer raises humidity noticeably in a small space.

Common mistakes

• Masking a burning smell — It is the one smell that is a warning rather than a nuisance. Restricted airflow and overheating lint smell hot before anything else happens.
• Cleaning the filter but not the condenser or water tank — Damp smells come from standing water. The tank and the condenser unit are where the water actually is, and neither is visible during normal use.
• Using dryer sheets to cover a smell — They add to the residue on the drum, the filter and the sensors, which makes both the smell and the drying time worse over a few months.

If it doesn't work

Questions people ask