How to Clean Your Dishwasher
Plus, find out what you can do to treat stains on your machine's interior.
The dishwasher works hard in your kitchen. Learn how to keep it functioning efficiently, and looking spic and span, with our full guide to cleaning it from inside out, according to Martha's Homekeeping Handbook ($25.65, amazon.com).
Cleaning the Exterior
Once a week, clean the dishwasher's door panel with a soft, lightly dampened cloth and dry thoroughly. Stainless steel can be cleaned with a commercial stainless steel spray. To clean the control panel, use a lightly dampened cloth (excessive moisture can damage the panel) and dry thoroughly. Dishwasher interiors are either stainless steel or plastic. Stainless steel is generally impervious to stains; plastic is more vulnerable.
To remove mildew from the interior or gasket, mix one part chlorine bleach to ten parts water, or mix one gallon of water with 1/2 cup of ammonia. Then wipe with a cloth or sponge, wearing rubber gloves. Note: Never mix bleach and ammonia together; doing so will result in dangerous, potentially lethal fumes. Don't use chlorine bleach to wipe out mildew if the machine has a stainless steel interior; bleach can corrode it. Run the dishwasher through a rinse cycle to remove any residual cleaner.
Cleaning Rust Stains
Iron and magnesium in the water usually cause rust. It can also come from a rusty water heater or rusty water lines. You can check for iron and magnesium by having an analysis done by a water treatment equipment company or testing laboratory. To find a local facility, contact your local cooperative extension system office. They should be able to tell you how to obtain a sample of your water and send it in for analysis. To remove stains, try a commercial rust treatment, such as RoVer Rust Remover. As a preventative measure, ask a plumbing contractor to install a filter that can aid in the control of rust.
Cleaning Brown Stains
Probably caused by a calcium or iron buildup, use citric acid (also known as sour salt) in liquid form, available at some large grocery stores (it was once widely used for canning) and many health food stores; you can also purchase it from some online retailers. Empty the dishwasher, fill the detergent cup with citric acid, and run a complete cycle. Run the dishwasher through a second cycle without the crystals but with detergent.
Cleaning Red Stains
Mostly caused by a tomato-based product, this kind of stain may be permanent but should fade over time with repeated washings. Staining can be minimized be removing any excess sauce from your dishes before loading the dishwasher.
Cleaning Green Stains
Caused by detergents that contain dye or color pigments, and this can be remedied as easily as switching to another detergent.
Cleaning White Film Buildup
This is caused by hard minerals and over time can cause damage to other components of the dishwasher. Install a water-softening system. You can temporarily remove the buildup by using citric acid, as directed for brown stains.
Cleaning the Interior—Including the Filter
After treating any stains, clean the interior of your dishwasher: Take the racks out, and use a toothpick to clear any gunk from the holes in the spinning arms. Wash the grate where the water drains, as well as the removable filter (if there is one) with warm, soapy water. Wipe the rubber door seal with a damp cloth soaked in vinegar. Sprinkle one cup of baking soda on the bottom, then run the machine on a short hot-water cycle to clean any remaining stains and odors.