How to Clean a Dishwasher: Filter, Spray Arms and Seal

How to clean a dishwasher: remove the bottom rack, take out and rinse the filter, clear the spray arm holes, wipe the door seal and edges, then run an empty hot cycle with a dishwasher cleaner or the cleaner your manual allows. Do it monthly and dishes come out cleaner with less odor.

How to clean a dishwasher: the quick answer

A dishwasher cleans dishes, not itself. Food scraps collect in the filter, minerals clog the spray arm holes and a film of grease coats the seal. When those build up, water cannot reach the dishes properly and the smell starts.

Quick facts: how to clean a dishwasher
Time	About 20 minutes of work plus one cycle
You need	Dishwasher cleaner or white vinegar, soft brush, toothpick, cloth
How often	Filter monthly; full clean every one to three months
Never	Mix bleach and vinegar; check the manual before using either

Step by step

1. Empty the dishwasher and pull out the bottom rack so you can see the floor of the tub.
2. Remove the filter. Most twist out of the base. Rinse it under warm water and scrub gently with a soft brush. Check the area under it for bits of glass or bone.
3. Check the spray arms. Spin them by hand and use a toothpick to clear blocked holes. Many arms unclip so you can rinse them.
4. Wipe the door seal, the edges and the tub walls with a cloth and warm soapy water.
5. Run an empty hot cycle with a dishwasher cleaner, or a cup of white vinegar in a dish on the top rack if your manual allows it.
6. Wipe and air out. Leave the door ajar so the tub dries.

What to use

Cleaner	Good for	Notes
Dishwasher cleaner tablets	Grease and limescale	Follow the pack
White vinegar	Light odors and film	Not with bleach; check the manual
Citric acid	Hard water scale	Often sold as a descaler
Baking soda	Freshening after a cycle	Sprinkle on the floor of the tub

Hard water and white film

A cloudy film on glasses and a chalky tub usually mean hard water. A citric acid descaler or a rinse aid, plus a water softener if you have one, helps. If the film returns quickly, check the rinse aid compartment.

Smells that cleaning will not fix

If you still smell sewage, check the drain hose loop or air gap and the sink trap. A hose that dips can let dirty water flow back. A smell like burning plastic or electrical heat means stop using the machine and have it inspected.

Keep it clean between deep cleans

Scrape plates instead of rinsing them fully, run hot water at the sink before starting, empty the filter regularly and leave the door slightly open after a cycle. That routine is the easy half of how to clean a dishwasher well.

Common questions about the smell and the film

A sour smell usually means trapped food under the filter or a drain hose that loops down and lets sink water creep back. A chalky film points to hard water. A greasy feel on the walls means the water is not getting hot enough or too little detergent is being used. Fix the cause that matches what you see, and the cleaning job gets easier each time.

A quick monthly routine

Once a month, pull the filter, rinse it, wipe the seal and run a short hot cycle with cleaner. Once a season, check the spray arms and the drain hose. Write the date on the inside of a cabinet door so you remember. This takes minutes and is the practical heart of how to clean a dishwasher without a big job.

When to call a professional

Call if water stays in the tub, the machine leaks, it does not start or the heater seems dead. These need diagnosis of a pump, valve or element rather than a deeper clean.

Related reading

• Dishwasher Smells Bad? How to Remove Odors and Find the Cause
• Dishwasher Not Cleaning Dishes? 9 Causes and Fixes
• Dishwasher Not Draining? 8 Checks Before You Call a Repair Pro
• How to repair dishwasher: A Step-by-Step Guide

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