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My dishwasher no longer cleans dishes as well as it did 5 years ago. Some info:

  • It is 10 years old, a low-end Frigidaire
  • we have hard water here (and no water softener)
  • I have cleaned the food trap at the bottom which helped

Any suggestions?

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Thanks. Tried several of these suggestions to no avail. Next stesp are to disassemble spray arm to clean and replace water inlet valve (basin doesn't look like it is filling all the way). In the meantime I've upvoted your answers. Thanks! –  Brian Low Dec 31 '10 at 4:00
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10 Answers 10

Some detergents will build up over time, gumming up the works. Try changing to a different kind.

Try vinegar. Pour some in to the dishwasher and run a "rinse and hold" cycle. It can clean out scaling from hard water, and detergent goops.

Check that the basin is filling up properly. I read that it's supposed to be just below the heating coil.

Check the water temperature. Let the machine run to fill the basin, then measure. If your hot water pipes are not insulated, insulate them. You can run the kitchen faucet for a minute to bring hot water closer, but it doesn't help much. Consider turning up the water temperature at the water heater. I did this and my dishes came out much cleaner.

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More info on water temp I found online: hot water should be at least 120*F, when heated should be 130*F - 140*F. –  Brian Low Dec 31 '10 at 3:58
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I guess we usually want the answers right here on the site, but I think this write-up was so detailed and thorough that I think the link is worth it:

http://www.wikihow.com/Clean-and-Maintain-a-Dishwasher

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Inspect the drain line (usually a flexible plastic pipe connected to the trap on your sink or disposal). Occasionally, this tube will become blocked and prevent the dishwasher from draining properly.

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Another thing you might look into is if your detergent has phosphates in it. Companies are having to put out solutions that no longer contain phosphates to comply with local/state laws that are being passed. You could be in an area that restricts the use of phosphates in detergent. I have not witnessed this myself, but the word is that the new phosphate-free detergents don't work very well.

Check out the Dishwasher Detergent Guide for more info:

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This happened to me. We have to use those packets that come with the jet-dry built-in plus Lemon Shine to get the dishes to not be cloudy. –  brian buck Nov 9 '12 at 22:46
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I had this issue with a dishwasher where the gasket/valve (rubber flapper thing) was warped from the heat/dishwasher soap or whatever and thus is was bypassing a cycle on the drain and part of the water was staying in the bottom of the dishwasher and the pump was not properly producing a full stregth of stream/water. Replaced that and it was fine.

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Since you mentioned hard water with no softener, there may just be too much calcium and other deposit buildup on the many internal parts. If you can, take apart the spray arms and other internal parts and soak them in CLR (Calcium, Lime, Rust) remover. This stuff works wonders on anything damaged by hard water.

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Two things to check:

  1. Check the pump and remove any debris. We had about 2 cups worth of debris (broken glass, nut shells, etc.).
  2. Check the blade on the grinder. Ours had been worn down and wasn't chopping up the bits fine enough.

If you call someone out get them to check both in one visit rather than have to call them out twice.

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It's the fact that the government regulated the use to Tri-sodium phosphate. It's no longer in your dish-washing detergent. You can still get the commercial products that contain phosphates. Phosphates were causing algae blooms (because they are just yummy food for any photosynthesis plant) in areas that don't have water treatment plants (ie. septic systems). You can also make your own TSP detergent by doing a little research on the internet. Watch out that you don't buy TSP from the hardware store. Make sure it's NOT the phosphate free kind. It's used in the paint section as it's a wonderful cleaning agent.

I've purchased a bunch of TSP detergent and my dishes are once again clean.

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-1 answer appears to be a copy of borq's –  BMitch Nov 10 '12 at 1:33
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I have found the the jets on the spray arms can also get clogged

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Welcome to the site Glenn. To improve your answer, you should describe how to check the spray arms for clogs and how best to clean them. –  BMitch Nov 10 '12 at 0:39
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Change detergents

We found changing from liquid to dry dishwashing detergent made a big difference. I suspect it is harder on the glasses and dishware though.

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protected by BMitch Nov 10 '12 at 1:36

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