Why does the washing machine smell bad (musty or rotten)?
A guide to the causes of bad odors in washing machines: mold biofilm in the door gasket, residue in the detergent drawer, constant low-temperature washes, and a closed door after use.
Recommended steps:
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1. Mold biofilm in the door gasket folds
The rubber bellows sealing the door has internal folds where water, detergent residue, and lint get trapped after every wash. In that dark, damp environment, a layer of biofilm (mold and bacteria) develops, producing that characteristic musty smell, especially at the bottom of the fold.
💡 Lift the rubber fold with your hand and wipe it with a cloth dampened in warm water and a few drops of bleach or white vinegar once a week, drying it thoroughly afterward.
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2. Detergent drawer with built-up softener residue
The softener compartment holds pasty residue that water never fully flushes away. That buildup over weeks or months breeds bacteria and mold just as easily as the door gasket does, and its smell is often mistaken for the machine's own odor.
💡 Pull the drawer out completely (it usually has a release catch) and soak it in hot water with vinegar once a month; scrub the internal channels it slots into with an old toothbrush.
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3. Exclusively washing at low temperatures
Always washing at 20-30°C saves energy but never reaches the temperature needed to dissolve grease and kill the bacteria that build up in the drum, the bellows, and the internal pipework. Over years, a biofilm forms that's hard to remove with a normal wash alone.
💡 Run an empty maintenance wash at 60-90°C once a month with a dedicated washing-machine cleaner or a cup of white vinegar poured directly into the drum.
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4. Door and drawer closed after every wash
Closing the door right after a wash finishes traps residual moisture inside the drum and bellows, creating the perfect environment for mold during the hours until the next load.
Frequently Asked Questions
How often should I run a maintenance wash?
Once a month is enough for most households. If you almost always wash at low temperatures or notice bad odor regularly, you can do it every 2-3 weeks until the smell fully disappears.
Is it safe to use bleach on the door gasket?
Yes, diluted in water and applied with a cloth occasionally, it's safe for the rubber; avoid using it concentrated or daily, as it can dry out and crack the material over time. White vinegar is a gentler alternative that's just as effective.