How to Clean a Dishwasher Inside — Toronto Home Guide

Dishwashers clean your dishes but accumulate food debris, grease, and mineral deposits themselves. A dirty dishwasher cleans poorly, smells bad, and can transfer residue back onto dishes. Monthly cleaning takes about 15 minutes of active work.

Filter Cleaning (Monthly)

Most modern dishwashers have a removable filter at the bottom of the interior:

1. Remove the bottom rack to access the filter — it usually twists counter-clockwise to unlock
2. Remove the filter and rinse under warm running water
3. Use a soft brush (an old toothbrush works well) with dish soap to scrub away grease and food particles from the mesh
4. Rinse thoroughly and reinstall — if the filter is clogged, the dishwasher cannot drain properly

Spray Arms

Clogged spray arm holes reduce washing performance:

1. Remove the spray arms — they usually unscrew or pull off their mounting post
2. Use a toothpick or thin wire to clear any clogged holes
3. Rinse under running water and reinstall

Interior and Door Gasket

1. Wipe around the door seal (gasket) with a cloth dampened in white vinegar — the gasket folds trap moisture and food residue that cause mould and odour
2. Wipe the inside of the door, the edges of the drum, and the interior walls with the same vinegar cloth

Vinegar Run (Deodorize and Descale)

1. Place a dishwasher-safe cup or bowl filled with 250ml of white vinegar on the top rack
2. Run a hot wash cycle with no detergent and no other dishes — the vinegar dispenses during the cycle, breaking down mineral deposits and deodorizing the interior

Baking Soda Run (Remove Stains)

1. After the vinegar run, sprinkle 1 cup of baking soda across the bottom of the empty dishwasher
2. Run a short hot cycle — this lifts staining and freshens the interior

Tips

• Scrape dishes before loading — dishwashers are not garbage disposals; large food particles clog the filter
• Run the hot water at the kitchen sink for 30 seconds before starting the dishwasher — it ensures the first fill uses hot water rather than the cold water sitting in the pipes
• Leave the door open slightly after a cycle to let moisture escape and prevent mildew inside