How To Clean a Dishwasher With Hard Water Buildup (guide for removal and prevention)

If you’ve noticed white or brown stains, spots, or film on your dishes after running them through the dishwasher, it’s likely that hard water buildup is the culprit.

Hard water contains minerals that can leave deposits and stains in your dishwasher and on your dishes, and over time, this buildup can affect your dishwasher’s performance.

But don’t worry, with the right cleaning methods and products, you can easily remove hard water buildup such as limescale from your dishwasher and keep it running smoothly.

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What is hard water buildup in dishwashers?

Hard water buildup in dishwashers is a common problem caused by mineral deposits that are left behind after the water evaporates.

When hard water is used to wash dishes in a dishwasher, the minerals in the water - such as calcium, lime, and magnesium - can attach to the surfaces inside the dishwasher and on the dishes themselves.

Over time, this buildup can cause stains, spots, and streaks on dishes and glassware. It can also affect the dishwasher’s performance by clogging the spray arm and other components.

Hard water buildup is a particular issue in areas with high mineral content in the water supply, but it can happen anywhere.

If left untreated, hard water buildup can lead to the need for costly repairs or even a shorter lifespan for your dishwasher.

That’s why it’s important to take steps to remove hard water buildup from your dishwasher and prevent it from happening in the future.

Signs of hard water buildup in a dishwasher

If you suspect that your dishwasher has hard water buildup, there are several signs to look for.

The most obvious sign is the appearance of chalky white or brown stains, spots, or film on your dishes after running them through the dishwasher.

You may also notice that your dishes don’t seem as clean as they used to, or that there is residue left on the inside of the dishwasher itself.

Another sign of hard water buildup is poor dishwasher performance, such as dishes that aren’t getting fully clean, the dishwasher making unusual noises, or the dishwasher not draining properly.

If you notice any of these signs, it’s important to take action to remove the hard water buildup from your dishwasher and prevent further damage.

How to remove hard water buildup in a dishwasher

Thankfully, there is an effective method for removing hard water buildup in your dishwasher.

Here are the steps to follow:

1. Empty the dishwasher. Before you begin cleaning, remove all dishes and utensils from the dishwasher.
2. Check the dishwasher filter. Locate the dishwasher filter (usually at the bottom of the dishwasher) and remove any debris or food particles that may have accumulated. If it has mineral deposits, soak it for an hour in some distilled white vinegar. For more information on cleaning a filter see this post - how to clean your dishwasher filter.
3. Clean the dishwasher spray arm. Remove the spray arm from the dishwasher and clean any mineral buildup or debris with a toothbrush or other small brush. For more information, see this post - how to clean your dishwasher spray arm.
4. Run a cycle with distilled white vinegar. Put back the filter and the spray arms. Then pour 2 cups of white vinegar into a dishwasher-safe container and place it on the top rack of the dishwasher. Run a hot water cycle on your dishwasher, without any dishes or detergent. The vinegar will help dissolve the mineral deposits and stains.
5. Run a cycle with baking soda. After the vinegar cycle, sprinkle 1 cup of baking soda on the bottom of the dishwasher and run another hot water cycle, again without any dishes or detergent. The baking soda will help neutralize any remaining mineral deposits and deodorize your dishwasher.
6. Wipe down the dishwasher interior. Use a damp sponge or cloth to wipe down the interior of the dishwasher, paying particular attention to areas with visible mineral deposits or stains.

If your dishwasher is badly clogged with hard water deposits, you may find that CLR does a better job than vinegar. Check out this post on how to clean your dishwasher with CLR.

Tips for preventing hard-water buildup in a dishwasher

Now you know how to get rid of hard water buildup in your dishwasher, how do you stop it from happening again?

Preventing hard water buildup in your dishwasher is easier than you might think.

The most effective way to prevent hard water buildup in your dishwasher is to use a water softener or a dishwasher salt specifically designed to soften the water. This can help to break down the mineral deposits in the water before they have a chance to accumulate in your dishwasher.

In addition to using a water softener or dishwasher salt, there are several other steps you can take to prevent hard water buildup in your dishwasher:

• Check your water hardness. If you’re not sure how hard your water is, you can purchase a water testing kit to find out. This will help you determine the best course of action for preventing hard water buildup.
• Use the right detergent. Make sure to use a detergent that is specifically formulated for hard water. These detergents contain ingredients that can help break down mineral deposits and prevent buildup in your dishwasher.
• Clean the dishwasher regularly. Regular cleaning of your dishwasher can help prevent the buildup of minerals and other deposits. Make sure to clean the dishwasher filter and spray arms at least once a month, and wipe down the interior of the dishwasher with a damp cloth or sponge.
• Use distilled vinegar or citric acid regularly. Running a cycle with white vinegar or citric acid regularly can help prevent mineral buildup in your dishwasher. Adding a half-cup of vinegar on the top rack of every wash can also help.
• Use rinse aid. Rinse aid can help prevent mineral buildup and improve the performance of your dishwasher.
• Don’t overload your dishwasher. Overloading your dishwasher can prevent water and detergent from reaching all parts of your dishes, which can lead to mineral buildup.
• Use the right cycle. Make sure to choose the right cycle for the level of cleaning your dishes need. Using a heavy-duty cycle for lightly soiled dishes can create excess suds and leave behind more mineral deposits.
• Rinse dishes before loading. Wiping dishes with a damp cloth before loading them into the dishwasher can help remove any excess food particles and prevent them from accumulating in the dishwasher.
• Avoid high-heat settings. High-heat settings can cause minerals to bond to surfaces in your dishwasher and on your dishes, leading to more buildup and cloudy glasses. Instead, use a lower temperature setting.

Frequently asked questions

How long do dishwashers last with hard water?

Hard water can shorten the lifespan of a dishwasher, but with proper cleaning and maintenance, a dishwasher can last up to 10 years or more.

Can you put limescale tablets in the dishwasher?

Yes, limescale tablets can help prevent hard water buildup in your dishwasher. Simply follow the manufacturer’s instructions for use.

What is the best limescale remover for dishwashers?

Distilled white vinegar and citric acid are both effective at removing limescale and mineral buildup from dishwashers. Simply run a cycle with either of these solutions to dissolve the deposits.

What does limescale look like in a dishwasher?

Limescale appears as white or brown stains, spots, or film on the surfaces of your dishwasher, dishes, and utensils.

What chemical would be used to remove hard minerals from a dishwasher?

Distilled white vinegar and citric acid are both effective at dissolving hard mineral deposits in dishwashers.

Why does my dishwasher have limescale?

Limescale in dishwashers is caused by hard water that contains high levels of minerals such as calcium, magnesium, and lime.

Why is there so much grit in my dishwasher?

Grit in your dishwasher can be caused by hard water buildup, or by food particles and debris that have accumulated in the dishwasher filter.

Does vinegar remove hard water stains in the dishwasher?

Yes, distilled white vinegar is an effective solution for removing hard water stains and mineral buildup in dishwashers.

Does dishwasher salt get rid of limescale?

Dishwasher salt is used to soften hard water and prevent mineral buildup, but it is not effective at removing existing limescale or mineral deposits.