A washing machine is meant to make things smell clean, so a musty or sour odour from the drum is unpleasant. The cause is nearly always the same: warm, damp conditions let mould and bacteria grow on residue from detergent, fabric softener and dirt. The good news is that it is usually easy to put right.
Why washing machines smell
- Washing at low temperatures every time. Cold and 30°C washes don't clear residue the way a hot wash does.
- Too much detergent or fabric softener. More than the machine needs builds up as a slimy layer in the drawer, seal and pipes.
- A shut door. Closing the door after a wash traps moisture inside.
- A dirty seal. The rubber door seal on a front-loader holds water, hair and fluff.
- A blocked drain filter or hose. Old water and debris sit there and smell.
How to deep clean a smelly washing machine
- Clean the detergent drawer. Pull it out (your manual shows how), wash it in warm soapy water with an old toothbrush, and clean the recess it slides into.
- Wipe the door seal. Pull the rubber back and wipe the folds with a cloth and warm soapy water, removing hair, fluff and any black mould spots. Dry it afterwards.
- Clean the drain pump filter. Switch off and unplug, put a towel and shallow tray down, open the small flap at the bottom front and unscrew the filter slowly, as water will come out. Remove fluff, coins and debris, rinse and refit firmly.
- Run a hot maintenance wash. With the drum empty, run the hottest cycle your manual recommends (often 60°C or higher, or a dedicated "drum clean" programme) with a washing machine cleaner made for the job.
- Wipe the drum and glass and leave the door and drawer open to dry.
Never mix cleaning products, especially bleach with vinegar or other acids, as they can release harmful fumes. Some manufacturers advise against vinegar or bleach because they can affect rubber seals, so check your manual first or use a washing machine cleaner designed for the job.
Stopping the smell coming back
- Leave the door and drawer ajar between washes so the inside can dry.
- Use the right amount of detergent. Follow the dose on the pack for your load size and water hardness, and use less fabric softener.
- Run a hot wash regularly, such as a 60°C cycle once a month, even if you normally wash cooler.
- Don't leave wet washing in the drum.
- Wipe the seal every week or two.
- Check the filter every few months.
When the smell is a fault
If the odour persists after a thorough clean, look for signs of a mechanical problem:
- Water left sitting in the bottom of the drum, or slow draining, which points to a blocked pump or hose
- A smell of burning or hot plastic, which means you should stop using the machine and unplug it
- A rotten-egg or drain smell that comes back quickly, which can point to a blocked or poorly fitted waste hose or standpipe
Our engineers repair washing machines of every make across Swansea, Mumbles and the Gower, from £70 + VAT with a 90-day guarantee. See our washing machine repair page, or read our washing machine troubleshooting guide.
Call us on 029 2088 5355 for a quote, or book online. Same-day or next-day where possible, repairs from £70 + VAT, and a 90-day guarantee on every repair.
Book a repair onlineFrequently asked questions
Why does my washing machine smell musty?
Damp residue builds up in the door seal, detergent drawer and drain filter, especially if the door is kept shut, you wash mostly at low temperatures, or you use a lot of detergent or fabric softener. Cleaning those parts and leaving the door open between washes usually fixes it.
How often should I clean my washing machine?
A monthly clean of the seal, drawer and filter, plus a hot maintenance wash, is a sensible routine for most households. Do it more often if you wash mostly at low temperatures or have pets.
Is it safe to use vinegar or bleach in my washing machine?
Some manufacturers advise against them, particularly on rubber seals, and you should never mix cleaning products. Check your manual first, or use a washing machine cleaner made for the job.
Could the smell be a fault?
Yes. A drain that is slow to clear, standing water in the drum or a smell of burning or electrics is not just dirt. A blocked drain, a failing pump or an electrical fault needs an engineer. Stop using the machine if you smell burning.
