For most people, the dishwasher serves a vital function in the home. When it begins to smell bad or lose its cleaning power, it's important to diagnose the cause correctly and act promptly to remedy the situation. When left unchecked, bad dishwasher odors can transfer to your dishes, glasses and utensils. Over time, this can affect the taste of food and even cause illness in some cases. Some causes of bad smells can also damage your dishwasher. The best way to deodorize your dishwasher depends in part on what's causing the smell. A little regular attention can keep it free of bad odors and operating at peak efficiency.

Dish washer
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Why Does My Dishwasher Smell?

Typical Causes of Bad Smells in Your Dishwasher

A number of factors could be behind a smelly dishwasher. One of the most common culprits is poor drainage. Not only can a blocked drainage hose cause mildew and mold, it can also lead to trapped food particles, adding to the bad smells.

Another frequent cause of odors is burned rubber on the dishwasher's heating elements. If a plastic container or lid falls to the floor of your machine, the dishwasher's heating coils can melt the item, creating a very unpleasant smell. Even after removing the plastic, the odors can linger for a long time.

Somewhat less commonly, the dishwasher's connection may make it susceptible to intrusion from sewage gas. Additionally, a buildup of water softening products can reduce the machine's ability to clean your dishes, resulting in trapped food smells that turn sour over time.

Remove Food and Any Blockages

First, check around the bottom of your dishwasher for any food or other substance that may be causing blockages near the drain. Remove the substance carefully.

Next, prepare some hot, soapy water and soak a clean cloth in the solution. Then, wipe down all the inside walls, door and any other accessible interior surfaces with the cloth. This will help clean up any leftover food that didn't make it down to the drain. Don't forget the interior seal around your dishwasher door, keeping an eye out for any signs of mold that may signal a leak that needs to be repaired professionally.

Finally, check the filter itself, as this is often the cause of unpleasant odors. Consult your machine's user manual for instructions on properly removing the filter. Immerse the filter in hot soapy water and clean it thoroughly, then replace it.

White Vinegar Removes Odors and Bacteria

If cleaning the interior and the filter doesn't completely eliminate the smell, try a white vinegar solution. Using a dishwasher-safe glass or bowl of sufficient size, pour two cups of white vinegar into the container, then place it securely on the top rack of the otherwise-empty dishwasher.

Set the dishwasher to its hottest water setting and run the machine through one cycle. This allows the water to mix with the vinegar and disburse it throughout the machine.

If you're not crazy about the smell of white vinegar, add a few drops of an essential oil, such as lemon, lemongrass, orange or peppermint to the bowl or glass.

Bleach and Baking Soda

You can also try other household items to remove bad odors from your dishwasher. Add a light sprinkle of baking soda over the interior of the dishwasher, but don't run the machine yet. Let it sit overnight first. In the morning, run the empty machine through a cycle on its hottest water setting.

Alternatively, try filling the machine's detergent compartment with bleach. Run through one cycle on the hottest water setting, then run it one more time to rinse away any remaining bleach residue. The bleach should kill whatever bacteria caused the bad odor.

Tips to Keep Your Dishwasher Odor Free and in Great Shape

To help keep your dishwasher free of bad smells and running at peak efficiency, follow these tips:

  • Clean filters and screens on a weekly basis to prevent it from happening again.
  • Don't leave your dishwasher half full of dirty dishes, waiting for more dishes to run a full load. Instead, run the dishes through a rinse-and-hold cycle first or rinse them thoroughly in the sink before putting them in the machine.
  • Don't divert water resources when the machine is running. Too little water can make it more likely that food will get trapped inside. Keep the kitchen faucets off while the dishwasher is operational.
  • If the smell persists, make sure there's no kink in your dishwasher's drainage hose. This can lead to backed-up water and trapped odors.
  • Don't forget to open the dishwasher's door when the cycle is finished. This allows the machine's interior to dry thoroughly. Damp walls can lead to growth in mildew and bad odors.
  • If all else fails, the odors could be related to sewage gas or smells. If that's the case, a plumber should be able to assist you in remedying the problem.