A washing machine that smells musty is washing your clothes in that musty smell. It's one of the most common — and most solvable — laundry problems. The cause is almost always mould or mildew growing in the drum, door seal, or detergent dispenser. Cleaning a washing machine takes about 30 minutes of active work and prevents both odour and performance problems.
Front-Loading Washing Machine
Front-loaders are more efficient than top-loaders but more prone to mould because the door seal (gasket) traps moisture. The fix is a combination of regular cleaning and an air-drying habit.
Step 1: Clean the Door Gasket
Pull back the rubber gasket folds and inspect the inside — this is where mould accumulates. Wipe thoroughly with a cloth dampened in a mixture of equal parts water and white vinegar or a diluted bleach solution (1 tablespoon bleach per cup of water). Work into every fold. If mould is established, let the solution sit for 5 minutes before wiping. Rinse with clean water and dry.
Step 2: Clean the Detergent Dispenser
Remove the dispenser drawer and wash in warm soapy water. Scrub the compartments with an old toothbrush. Clean the cavity the drawer slides into — this area often has mould at the back. Rinse well and dry before reinserting.
Step 3: Run a Cleaning Cycle
Add 2 cups of white vinegar directly to the drum (not the dispenser). Run a hot, full wash cycle. This deodorizes and descales the interior. If you have a "drum clean" or "tub clean" setting, use it.
Step 4: Second Cycle with Baking Soda
Sprinkle ½ cup of baking soda into the drum and run another hot cycle. This further deodorizes and addresses any residue left by the vinegar.
Prevention: Leave the Door Open
The single most effective front-loader maintenance habit: after every wash cycle, leave the door and dispenser drawer slightly open. This allows the drum and gasket to dry out between uses, which is what prevents mould from growing in the first place.
Top-Loading Washing Machine
Top-loaders don't have the gasket problem but can still develop limescale buildup, residue in the agitator, and odour in the tub.
Step 1: Run a Hot Cycle with Vinegar
Set the machine to the largest load, hottest water setting, and run a cycle. When the tub is full and the agitator starts, pause the machine and add 4 cups of white vinegar. Resume and let the cycle complete.
Step 2: Wipe the Drum and Agitator
After the cycle, wipe down the inside of the drum with a cloth — this removes loosened residue. For removable agitators, unscrew and clean underneath (mould often grows there in older machines).
Step 3: Baking Soda Cycle
Run another hot full cycle with 1 cup of baking soda in the drum.
Step 4: Clean the Lint Filter
Some top-loaders have a lint filter — check your manual for location and cleaning instructions. A clogged lint filter reduces washing performance and can cause odour.
How Often Should You Clean the Washing Machine?
- Front-loader drum clean: monthly
- Top-loader drum clean: every 3–6 months
- Front-loader gasket wipe: weekly or after every load
- Detergent dispenser: monthly
Washing machines are part of the laundry room scope in Maidless's deep cleaning service in Toronto. Book a Toronto deep clean — HST included.