Maintaining dishwashers: a practical guide

To keep your dishwasher in good shape, consider this practical guide.

• One small nick in a vinyl-coated rack can start off a rust invasion that will stain your dishes and cookware and eventually ruin your dishwasher. Act quickly. Get a new rack or repair the vinyl coating.
• If the racks in your dishwasher have begun to rust, you may be able to avoid further damage with a special paint made for coating damaged areas on dishwasher racks. Unlike other paints used for containing rust, it won't come off on your dishes. It's heat-resistant, has a rubberized finish, and comes in a range of colours. Buy it in small bottles with a brush in the cap from appliance parts suppliers.
• To remove the chalky mineral deposits known as limescale from your dishwasher, empty the machine, fill it up again, add a cup of white vinegar, and run it through a cycle. Then add normal dishwashing detergent and run it through another cycle. Don't do this too often, however – vinegar is an acid and will cause damage to the materials inside the dishwashing machine if used excessively.
• Arrange items in the cutlery basket – especially sharp knives – with their blunt ends uppermost so they won't damage the racks or the door seal. Other items that have sharp edges such as pans and colanders are best washed by hand.
• Iron in the water is the usual cause of blotchy yellow or brown stains in a dishwasher. To remove stains, let the empty machine fill, add half a cup of citric acid crystals, and run it through a cycle. For a permanent solution, put an iron filter on your water supply.
• A cracked washer arm can produce a powerful, erratic spray of water that may knock over glassware and breach the door seal, causing breakage and flooding. Mend the crack with a little household epoxy cement. If it doesn't hold, replace the washer arm.
• If your dishes have mysterious black smears, it may be the result of metal utensils rubbing against them in the dishwasher. Separate pots and dishes when you load. Also, don't put in any disposable aluminum containers. The thin aluminum material tends to break down in the heat of the washing cycle and marks the surrounding dishes.
• A regularly cleaned dishwasher will work more efficiently and last longer. Check your appliance's manual for specific advice.

• Screwdriver, wrench or socket set
• Unwound paperclip or pipe cleaner

• Some lower spray arms have clips or tightly fitted screws.
• Others simply lift off, or have screws that you can remove by hand.
• Once the arm is removed, lift out the strainer (filter or screen) on the floor of the dishwasher and clean it.

• To remove the upper spray arm, unscrew the retaining clip, then remove the centre screw to disconnect the arm from the water channel.
• On some models, you'll need to remove the tray and unclip a protective grid before you remove the centre screw.

• Clean any blocked openings in the spray arms with an unwound paperclip or pipe cleaner.
• Flush water through the arms while tilting them back and forth to wash out foreign objects.
• Follow these steps in reverse (starting with step 2) to reinstall the arms.

Follow this practical guide to help keep your dishwasher in good shape.