What is the white gunk in my dishwasher & how can I clean it?

You open your dishwasher, expecting to find sparkling clean dishes, but instead, you’re greeted by a stubborn white film clinging to the interior and sometimes your dishes. This residue is more than just an eyesore; it can affect your dishwasher’s performance and the cleanliness of your dishes.

But what exactly is this white gunk, and how can you get rid of it for good? Don’t worry! We’ll help you understand what’s causing the problem and walk you through practical steps to clean your dishwasher and prevent the buildup from coming back.

What is the white stuff in the dishwasher?

In most cases, the white residue is caused by mineral deposits, particularly calcium and magnesium, from hard water. When the water in your dishwasher evaporates, these minerals are left behind, forming a chalky film. If you have hard water, this buildup is likely to happen more frequently.

Another common culprit is soap scum, which forms when detergent combines with hard water minerals or grease. And don’t forget food particles, leftover bits can mix with grease and detergent, creating a nasty sludge that adds to the gunk.

Where does white stuff form in the dishwasher?

Hard water is the biggest offender. The higher the mineral content in your water, the more likely you are to see residue over time. If you suspect hard water is to blame, testing your water’s mineral content can confirm it. You can use a water hardness test strip (available at most hardware stores) or try a simple DIY method: fill a bottle with water and a few drops of liquid dish soap, shake it, and see if it creates suds. If it doesn’t, your water is likely hard.

Overloading the dishwasher or using too much detergent can also make it harder for water to rinse everything clean, contributing to buildup. Using too much detergent can cause excess soap to combine with hard water minerals, leaving a sticky residue behind. Conversely, using too little detergent may not effectively clean grease and food particles, allowing buildup to accumulate. Check if you’re following the recommended amount for your water type.

Read more: Dishwasher Won’t Dispense Detergent: Top Five Reasons and Fixes

Cleaning the white gunk

Now that you’ve assessed the situation, it’s time to roll up your sleeves and give your dishwasher the deep clean it deserves. Don’t worry, it’s easier than you think, and you likely already have most of the tools and supplies you’ll need.

What you’ll need

• white vinegar
• baking soda
• a small scrub brush or old toothbrush
• a microfiber cloth
• gloves (optional, but helpful for scrubbing)

How to clean the dishwasher

1. Empty the dishwasher: Take out the racks, utensil holders, and any removable parts to give yourself better access. This also ensures you can clean these components separately.
2. Clean the filter: Locate the filter, usually found at the bottom of the dishwasher. Twist it out, rinse it under warm water, and use a brush to scrub away any grease or trapped food particles. A clean filter ensures proper drainage and prevents future buildup.
3. Wipe down the interior: Dip a microfiber cloth in white vinegar and use it to wipe the interior walls, door, and rubber seals. Pay special attention to corners and crevices where residue tends to accumulate.
4. Unclog the spray arms: Remove the spray arms (if possible) and check for clogged holes. Use a toothpick or thin wire to clear any debris. Clogged spray arms can reduce water pressure and affect cleaning performance.
5. Run a cleaning cycle with Affresh: Place an Affresh dishwasher cleaner tablet in the detergent dispenser or at the bottom of the dishwasher (follow the manufacturer’s instructions). Run an empty dishwasher on the hottest cycle to break down mineral deposits, grease, and soap scum.
6. Run a vinegar cleaning cycle: For an extra boost, follow the Affresh cycle with a natural cleaning products. Place a cup of white vinegar in a dishwasher-safe container on the top rack. Run a hot water cycle with the dishwasher empty. The vinegar will dissolve mineral deposits, grease, and soap scum.
7. Add a baking soda boost: After the vinegar cycle, sprinkle a cup of baking soda on the bottom of the dishwasher and run another hot water cycle. This step deodorizes and polishes the interior, leaving your dishwasher fresh and sparkling.
8. Clean the removable parts: While the dishwasher runs its cycles, scrub the racks, utensil holders, and other removable components with warm, soapy water. Let them dry completely before putting them back in.

Read more: What cycle should I run my dishwasher on?

FAQs

Why does the white gunk appear even though I clean my dishwasher regularly?
If you’re dealing with hard water, mineral deposits can form quickly despite regular cleaning. Using a rinse aid, a hard water-specific detergent, or installing a water softener can help minimize this problem.

Can I use bleach to clean my dishwasher?
While bleach can be effective for tackling mold or mildew, it’s not ideal for removing mineral deposits or soap scum. Also, avoid using bleach if your dishwasher has stainless steel parts, as it can damage the finish. Stick to vinegar and baking soda for a safe, natural clean.

Is the white gunk harmful to my dishes or health?
The gunk itself is usually harmless—it’s primarily composed of minerals and soap residue. However, it can affect the cleanliness of your dishes, leaving an unpleasant film. Regular cleaning ensures your dishes come out truly clean and safe to use.

What if my dishwasher still smells bad after cleaning?
Lingering odors can occur if grease or food particles are trapped in hidden areas, like the drain or spray arms. Double-check these spots and consider running a vinegar and baking soda cycle to neutralize odors.

Should I hand wash my dishes before putting them in the dishwasher?
It’s unnecessary to pre-wash your dishes, but scraping off excess food debris is a good idea. Modern dishwashers and detergents are designed to handle light residue effectively. Overloading your dishwasher or leaving excessive food bits can contribute to buildup, so load your dishes properly.

Can the white gunk damage my dishwasher?
If left untreated, mineral deposits and soap scum can reduce your dishwasher’s efficiency. Over time, they may clog spray arms, filters, or drains, potentially leading to costly repairs. Regular cleaning and maintenance help protect your appliance and keep it running smoothly.

Read more: How to Clean a Dishwasher

Additional information

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