Occasionally you need to clean your dishwasher of sediment like hard water deposits, food particles or rust. It is an easy do it yourself project and it can prolong the life of your dishwasher. Not doing this occasional maintenance can shorten the life of a dishwasher, especially in hard water areas.
For food particles, check with your owners manual on how to remove the bottom strainer that most newer dishwashers have. Take it out and dump anything that is in it into the trash and then wash with hot water and dry. Even dishwashers with the 'no scrape' feature generally have to be cleaned like this occasionally to avoid odors.
Hard Water Sediment
For hard water sediment there are several ways to clean your dishwasher. Remove all dishes, silverware, glassware and such from your dishwasher. Put in a cup of citric acid which you can purchase at most supermarkets or drugstores. Set the dishwasher on the setting with the hottest water temperature and run through a complete cycle. This should totally remove all sediment. If you can't find citric acid, use the drink mix Tang as it contains high amounts of citric acid.
Another cleaning treatment is to follow the above steps but put in 2 cups of white vinegar and run through the hottest water cycle.
If any sediment remains, use a nylon scrub pad to gently scour it away.