How to Clean and Maintain a Dishwasher
Why is my dishwasher not cleaning properly?
When working on appliances, please follow safety procedures. Click here to see safety guidelines.
Do you have problems with your dishwasher leaving spots, grime or deposits on your dishes and silverware? This is a common complaint. There are several causes for poor cleaning performance. Some of them are simple to repair and will garner great results. There are things you can do to change the performance of your dishwasher. Click here to see how a dishwasher works.
The first order of business is to clean the inside of the dishwasher. Start by making sure the screens are clean. Most dishwashers have a couple of screens to keep large particles out of the pump and drain. These are normally located on the bottom and back of the dishwasher.
The screen on the back of the dishwasher is generally a recycling screen where the water is screened during the wash and rinse cycles. Remove the bottom rack and set it aside, inspect the screen on the back of the dishwasher, if it looks like it can be removed, remove it and wash it in soap and water and then in vinegar. This will remove deposits that may be preventing adequate water flow. Check under the screen for any particles that may have collected and clean them out. Use caution here because small pieces of glass and other debris could be collected behind or or under filters and screens.
CAUTION: No Bleach!
CAUTION: I don't care what you have read or heard elsewhere, do not use bleach. Do not use chlorine products at all. Bleach will damage parts of the dishwasher that you cannot see. It may damage stainless steel, bleach combined with other chemicals becomes toxic and should never be used in a dishwasher. Period. Don't use it. I know that you may have read other places that it is ok to use bleach in some situations, but I advise against it. Believe me, bleach is not a good dishwasher cleaning agent.
If you do decide to use bleach anyway, please use it sparingly, like two tablespoons. It will kill mold that other cleaners may not. Personally, I would never use bleach.
Clean the Dishwasher Screens
Next look at the bottom of the dishwasher in the back, there may be a large screen normally held down with two screws or nuts. Remove them (quite often they are ¼ inch nuts), and then the screen cover will come off. Use great caution in cleaning this area, normally the pump inlet is located here with a trap and possibly a soft food disposer. This is where it is most likely to have splinters of glass and bits of metal that have collected over time. You must be very careful not to injure yourself on this debris. The soft food disposal is normally a stiff wire that spins over the pump inlet and breaks up any food that may come through. The trap consists of a well in front of the inlet. Heavier things fall into this well and are trapped there, they mostly consist of glass, bits of metal and bone, rocks, small screws and plastic. There have been a couple of times I looked into one of these and found pieces of plastic bag wrapped around the soft food disposal and practically blocking the water flow. Cleaning this out made the dishwasher run like new.
Some dishwashers have the screen in the center. These can be easily removed in a similar manner. Once removed, use a stiff dish washing brush to scrape the debris off the surface. Clean this area carefully, there will undoubtedly be shards of glass and other small sharp items that can cause injury.
Time to Replace Your Dishwasher? Consider these:
Clean the Dishwasher's Rotating Arms
The arms are designed to rotate and spray water out at the dishes. Check to make sure the arms are rotating freely and that the small spray holes are clear. If there is something blocking the openings, then they need to be cleaned out. Most of these can be cleaned with a toothpick and pipe cleaners. Using a small pair of needle nosed pliers may be necessary. Be gentle here, the items can be damaged easily. Other metal tools need to be used with caution. If they are blocked and cannot be cleaned, you may have to disassemble the washing arms may be required. This is normally not too difficult and can be accomplished by removing a hold down fastener normally located in the center of the dishwasher. The spray arms then can be lifted from the center. If you have to remove the spray arms or any other parts, be sure to lay them out in the order that they are taken out so that you can reassemble them in the same order. You may find a part that is damaged and you wish to replace it. Be sure to make some notes as to the order of re-assembly, this tactic will save you about a million hours in re-assembly. Another tactic is to take a pencil or grease pencil and mark the parts with numbers, the first item removed is marked with a #1, then #2 on the second part, etc. If you have 3 parts they are numbered in sequence and can be re-assembled easily. I always take the additional precaution of labeling them all on the top or bottom so that I know the direction for placement on the re-assembly.
Once you have completed these tasks, give yourself three cheers, the hard part is over.
Clean the Dishwasher Seals
Now you need to wipe the surfaces that are normally neglected. Open the dishwasher and use a damp cloth with soap and water and wipe the seals along the door. These areas are often neglected and need to function well to keep the dishwasher watertight. Wipe them clean and make sure you do not leave soapy water behind. You can spray window cleaner on the cleaned seals to remove the soap residue. If the seal seems worn or brittle, dry the seal and spray it with pure silicon spay. This will lubricate the seal and help protect it. Wipe the excess off.
Care of the Heating Element
Now for the inside of the dishwasher. Most dishwashers have a heating element in the bottom of the unit. This element normally does not need any kind of cleaning. It gets really hot and can burn you or melt plastic. It is a fairly easy to damage the element, so if it looks ok, leave it alone. If there is melted plastic on it, see if it can be removed by using a plastic scraper. Never scrape it with a metal tool. Replacing the element is normally a BIG JOB. Don't do too much here. If the element has scale or smells burned, then a descaler may need to be used. I would start with vinegar. Start the diswasher and wait for it to fill part way. Then add about two cups of white vinegar and allow it to complete the cycle. If this is ineffective, then use a de-liming agent such as lime away or a product that is designed to clean scale out of dishwashers. Do not use this product in the dry cycle. After the initial application, run the dishwasher through a complete cycle. This will rinse this out of your dishwasher. Remember, most of the time the element needs not attention.
The breakfast drink: TANG
The best cleaner for inside a dishwasher is the breakfast drink Tang. It is perfect, and has the perfect balance of chemicals to thoroughly clean the dishwasher. Fill the dispenser cup, the initial wash cup and add about a half cup to the inside of the dishwasher. Run it through a regular cycle. You will be astonished at the result. Brown stains and faded portions will be restored to their original condition. Very dirty dishwashers may require more than one application of Tang.
Stock up on Tang, it Works Wonders
Regular use Dishwashing Detergent and Rinse Agents
Clean your dishes with a premium dishwasher detergent such as Cascade. There are abrasives found such as sand in some cheap detergents that will ruin some of your dishes and shorten the life of your dishwasher. This is one time that brand name products are worth the extra money.
Using too much detergent will result in poor cleaning results. Try using less.
If you have a water softener, do not use rinse agents.
If you have spotting and clouding of glassware, you probably need a rinse agent.
More by this Author
It is obvious that a dishwasher uses hot water and specially designed detergent and rinse agents to clean, disinfect and dry your dishes. Too bad the dishes cannot put themselves in the dishwasher. The machine...
Just when you thought you would not have to read anything else about a dishwasher, you get this. See: How does a dishwasher work? and the ever popular cleaning strategies to improve the cleaning power of a...
Always unplug the refrigerator before you work on it. Review safety procedures. The most common problem in a refrigerator that is leaking is a plugged drain. All frost free refrigerators have a defrost cycle that...