How to Get the Most from Your Dishwasher

Written by Mark Kelly of Kelly's Appliance Center
Updated January 6, 2015
If your dishwasher has never been cleaned or it has a lot of lime buildup, you need to do a deep cleaning. (Photo by Eldon Lindsay)

A dishwasher can use less energy than washing dishes by hand, but only if it's running efficiently. Learn how dishwasher maintenance can ensure top performance.

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We’ve seen the statistics: washing dishes by hand can use more time, water and energy than cleaning them in the dishwasher.

But that's if your dishwasher is running efficiently.

Today’s highly efficient and effective dishwashers need routine maintenance.

For clean dishes, clean the dishwasher

Filters: In most of the European-style dishwashers you will find removable filters or screens in the bottom of the dishwasher. They need to be removed and cleaned monthly.

Buildup: Due to hard water, mineral deposits can build up in your dishwasher on the walls and inside the pump and wash arms.

If your dishwasher has never been cleaned or it has a lot of lime buildup, you need to do a deep cleaning. The best method I have found is to pour a half gallon of white vinegar in the dishwasher tub and let soak for about an hour. Then on the hottest setting (such as “sanitize” or “pots and pans”) I run a cycle using a dishwasher cleaner. Some types of powder cleaners are placed in the detergent dispenser; others types of cleaners go in the silverware rack. Follow the directions on your dishwasher cleaner.

Once you have done a deep cleaning, you can prevent lime and calcium from building up by reducing the amount of detergent you are using and buying a good-quality detergent. This should reduce the buildup and increase the amount of time between cleanings.

The chemistry of dishwashing detergents

There are many kinds of dishwasher detergent on the market. Two of the most popular are Finish (made by Reckitt Benckiser) and Cascade (Procter & Gamble).

There are two types of cleaning agents in dishwashing detergent: enzymes, which break down proteins; and starches and bleach, which clean stains such as coffee and tea.

The other ingredients in a good detergent are citrates, which soften the water to help in cleaning, and a rinse function that helps eliminate streaks and spots when drying.

Types of dishwasher detergents


A gel is the least effective type of detergent because it only contains one of the cleaning agents.


Powdered detergent contains both enzyme and bleach and does a good job, unless it gets wet prior to use. If your box of powder has hardened, the detergent has already been activated and will not clean properly.


For best results I recommend the tablets. Finish All In 1 (the one with the red powerball) works well if your water’s hardness measures 9 grains per gallon or less. A more powerful dishwasher detergent tablet, Finish Quantum, will work in harder water (up to 19 grains per gallon).

Because these tablets have a rinse factor, in some cases a rinse aid is not needed. If the dishes don’t come out as dry or spot-free as you would like, you can use a rinse aid, such as Jet Dry, in addition to the tablet. This lowers the surface tension of water, allowing it to slide off your dishes.

What about hard water?

If your water measures harder than 19 grains per gallon, you should use a cleaning booster (such as Glass Magic or Lemi Shine).

Did you know?

Putting detergent in the prewash dispenser often is not effective, because the water is not yet very hot, and the cycle is short.For those people who don’t like to use bleach on their dishes, Finish has come out with a bleach-free product. Labeled “Power & Free,” it has a white label instead of blue.

About this Experts Contributor: Mark Kelly of Kelly's Appliance Center has been providing  home appliance repair and service in Marin and Sonoma counties in California for 30 years.  You can follow this contributor on Twitter and Google+.

As of January 5, 2015, this service provider was highly rated on Angie's List. Ratings are subject to change based on consumer feedback, so check Angie's List for the most up-to-date reviews. The views expressed by this author do not necessarily reflect those of Angie's List.

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