How To Clean A Dishwasher
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Mineral buildup, mold, and food residue may be clogging your dishwasher’s spray arms and filters.
Before You Begin
You may have read that you can clean your dishwasher by putting a cup of bleach or vinegar on the top rack and running it. The claim is that the liquid will splash around and clean everything, but places like your filters, gasket, and spinning arms need additional care. The method below removes food residue, broken glass, and other matter in your spray arms and filters, and ensures your door gaskets are clean so they seal well.
Equipment and Materials You’ll Need
- Old toothbrush
- Tweezers
- Nail scissors
- Toothpick or pipe cleaner
- Flashlight
- Microfiber cloth
- Measuring cup
- 3% hydrogen peroxide
- Spray bottle
- Liquid dish soap
- Distilled white vinegar
- Pliers (sometimes)
Steps To Clean Your Dishwasher
Time required: 15 minutes of active effort, plus a complete dishwashing cycle.
Safety tip:
It’s not uncommon to find silvers of glass in the bottom of your dishwasher. Before you begin, use the flashlight to check. You can safely remove these shards with a wet/dry shop vac, a lint roller, or by pressing a piece of bread onto them to lift away the pieces.
Step 1: Clean the racks and utensil holder.
Remove the racks and utensil holders from your dishwasher and wash them in a sink of warm, soapy water. Dip the toothbrush in baking soda and scrub any hard mineral buildup you discover, then sprinkle it with vinegar so the fizzing action dislodges the mess. Pay special attention to the tracks and wheels, which collect a lot of grime. Use the tweezers and nail scissors to remove threads wrapped around the utensil basket, then scrub it in warm, soapy water and let it air dry.
Step 2: Inspect and clean the spray arms.
Unscrew the spinner arms and inspect the holes for debris or bits of food. If you can’t remove the arms, use the flashlight and examine them in place. Use the tweezers or pliers to pull out anything lodged in the holes, and poke the toothpick or pipe cleaner into each hole to break through mineral buildup and clogs.
Step 3: Remove and scrub the upper filter.
The upper filter is round and sticks up from the floor of your dishwasher. Turn it gently and remove it. If you’ve never cleaned yours before, expect to find a thick layer of soap scum and greasy residue. Soak it for several minutes in warm, soapy water, then sprinkle it with baking soda and scrub with the toothbrush to remove the grime. Rinse it under a running faucet or your sink’s sprayer hose and let it air dry.
Step 4: Remove and scrub the lower filter.
The lower filter is the mesh screen on the bottom of the dishwasher. Not every model has one. Remove it by turning the knobs that fasten it, then lift it carefully from beneath the heating element. Scrub it in soapy water and use the brush to dislodge anything stuck in the mesh. If the filter is not removable, scrub it in place with a minimal amount of water, then wipe it dry.
Step 5. Clean the door and gasket.
Clean the interior of your dishwasher door with warm, soapy water and a sprinkle of baking soda. Open it all the way and reach inside to wipe beneath the bottom edge where food residue collects. Next, clean the door’s rubber seals and gasket with hot, soapy water. Spray mold or mildewed areas with hydrogen peroxide and let it air dry, then wipe it again with a clean, damp cloth.
Step 6. Run a hot wash and dry cycle.
Put the screen, filter, racks, and utensil holder back into your dishwasher. Select your machine’s longest, hottest cycle–usually the sanitize setting or temperature boost. Do not add detergent or dishes. After the cycle has run for 10 minutes, open the door to pause it and pour 1 cup of white vinegar into the bottom of the machine. Resume the cycle and let your dishwasher finish cleaning itself.
Frequently Asked Questions
Below are some common questions about cleaning dishwashers and related problems. If you have a question not answered here, please leave it in the comments. I update this section routinely, so the answer to yours may help other readers, too.
How often should I clean my dishwasher?
Wash the round filter and wipe the door gasket and seals every week. Twice a year, or any time you notice dishes are not getting clean, give your dishwasher a thorough deep-cleaning.
Can I use something besides bleach or vinegar?
There are dishwasher cleaning tablets you add to the bottom of the machine when you’re doing the dishes. Affresh is one brand. These are mostly citric acid, so you could get similar results by sprinkling a packet of unsweetened Lemon Kool-Aid or powdered Tang in there.
Why does my dishwasher leave rust spots on my dishes?
Rust on plates and silverware is often the result of damaged, rusting dishwasher racks. Inspect the coating on the tines of your racks for nicks or peeling. You can order replacement racks on the manufacturer’s website. To fix them yourself, use a rubberized sealant that can handle the extreme heat in dishwashers. Plastidip is one brand.
If your dishwasher gives off a bad odor after running it, or the dishes have a yucky film on them, it could be that the drain hose from your dishwasher is lacking a high loop. The drain hose needs to go up high, then down again, to prevent the dirty water from going back into the dishwasher. If the drain hose is long enough, you can easily fix it yourself with a nail and a zip tie. It’s a little more complicated if your drain hose is too short, as you’ll have to attach more hose or replace the hose with a longer one. Instructions are available on the web.
That’s an excellent point. I just disconnected and removed my dishwasher as part of a DIY kitchen remodel. There’s a bracket on the side of my dishwasher to hold the drain hose high, so it loops up from the bottom of the dishwasher to the bracket and back down again to where it connects to the sink drain. I suspect a large 3M hook and ziptie would be better than using a nail for those whose dishwashers don’t have such a bracket.