How to Clean a Humidifier

Keeping air clean and moist.

Low humidity can cause irritated eyes and sinuses and dry, flaky skin. So it’s important to keep the humidity at a comfortable level.

Humidifiers work effectively at increasing the moisture in the air. They make it more comfortable for you and your family. When properly maintained, a humidifier can last for years, but improper maintenance can lead to a few issues.

Mold, limescale and other contaminants quickly build-up inside the tank and mist outlet. If this occurs, contaminants will spread through the air that you inhale. As a result, your humidifier could be causing more harm than good.

Fortunately, knowing how to clean your humidifier is as easy as it can get.

How to Clean a Humidifier

There are several ways to get the task done depending on how dirty it is. We’ll show you the most common ways to clean your humidifier, starting with a basic clean you can do regularly.

Cut Power First

Before you get started, make sure you unplug your humidifier. If you have a warm-mist humidifier, leave it to cool for 30 to 60 minutes before handling it to avoid any burns.

Basic Humidifier Cleaning

Basic cleaning should be done regularly, depending on how often you use your humidifier. It doesn’t take long and all you need is the following:

  • Towel.
  • Clean water.
  • White vinegar.
  • Sponge.
  • Cloth.

1. Rinse the Filter

After unplugging the humidifier, remove the filter and rinse it underneath the running faucet using cold water. Turn it every so often to ensure you clean all sides thoroughly. Then, place the filter on a clean towel and allow it to dry.

If your filter is starting to look worn, consider replacing it with a new filter. You can check the manual to see instructions on how to replace it and how often it should be done.

Keep In Mind

Avoid using any cleaners or chemicals on the filter as these can damage it.

2. Clean the Tank

Remove the tank from the humidifier and empty the contents into the sink or drain. Next, fill it halfway with pure white vinegar and swish it around to cover the bottom and sides. Allow the vinegar to sit in the tank for at least one hour.

Vinegar is a highly effective natural cleanser. Because it’s high in acid, it effectively dissolves mineral build-up and limescale. It can even remove mold.

If your tank is rather filthy, use a sponge to gently scrub the bottom and sides. You can also use a cotton swab to really get into the tight corners.

Additionally, if your tank is small, you can add a small handful of rice with the vinegar and shake the tank. The rice will create a slurry and help dislodge gunk.


Avoid using any other types of commercial cleaners when cleaning your humidifier. A chemical residue could be pumped back into the air even after cleaning. Vinegar is natural and, therefore, won’t cause any harm.

3. Rinse

After pouring out the vinegar, rinse the tank thoroughly with cold, clean water. You might need to rinse it several times to get rid of the vinegary scent.

4. Clean the Frame

Now that the tank is sparkling clean, it’s time to finish off with the frame. Simply dampen a sponge in a mixture of vinegar and water and wipe the entire frame. Pay close attention to any small creases or crevices around the panel or dial.

5. Reassemble

Take a clean cloth and wipe the frame and tank to remove excess water. Place the dry filter back into the humidifier, fill it with water and enjoy a clean mist.

Disinfecting a Humidifier

Once in a while, it’s important to disinfect the humidifier. As we mentioned earlier, mold, bacteria and contaminants are prone to residing within the tank and outlet. Here are a few ways to disinfect your humidifier.

Keep In Mind

The following methods use bleach, vinegar and peroxide; however, these items should never be mixed. Mixing chemicals can create toxic fumes or byproducts that can harm you and your family (1). Choose one of the following methods and rinse thoroughly.

Method 1: Bleach

Bleach is a hard chemical, but it’s sometimes necessary to properly disinfect the tank. Fill the tank with clean water and add one to two teaspoons of bleach depending on how large the tank is. Allow the solution to sit for up to one hour to sanitize the tank. Avoid leaving it for any longer since the bleach can cause damage.

When the hour is up, pour the solution into a sink or drain and rinse the tank thoroughly with cold water. Make sure it’s rinsed properly before placing it back onto the frame.

Method 2: Vinegar

Pour one cup of vinegar into the tank and fill the rest of it with clean water. Place the tank on the frame and allow the humidifier to run for one hour — the vinegar will clean the mist outlet as it runs. Avoid running the humidifier indoors since it will make your home smell very strongly of vinegar.

Never do this with chemical cleaners or bleach as it will damage the internal parts of the humidifier. Additionally, it will spread the chemicals in the air.

Once the hour is up, empty the contents of the tank and rinse with clean water. Fill it once more with clean water and allow the humidifier to run for an hour to remove any vinegar that might be hiding in the outlet. Rinse the tank one last time once the hour is up.


Never add essential oils to your humidifier to get rid of the vinegary scent unless recommended by the manufacturer. Essential oils can damage the humidifier. Instead, rinse thoroughly with water until the scent is gone.

Method 3: Peroxide

Peroxide is a milder form of bleach, but just as effective. All you have to do is fill the tank halfway with peroxide and swish it around to cover the bottom and sides. Leave the peroxide to sit in the tank for up to an hour before pouring it out. Then, rinse thoroughly with cold water.

Regular Maintenance

Cleaning your humidifier isn’t an everyday task. However, there are a few things you should do regularly to keep bacteria at bay.

1. Change the Water

Your humidifier might be able to hold over a gallon of water, but unless you’re going to run it continuously, it needs to be emptied.

When you leave the water to sit in the tank for an extended period, mold and bacteria are likely to grow. We recommend that you empty your humidifier daily or every other day to avoid bacterial growth or mold.

2. Clean Regularly

Depending on how often you use your humidifier, we suggest you do a basic clean every three days. You can either do a basic clean or disinfect the tank using one of the above methods. Deep clean the humidifier every two weeks depending on usage.

3. Avoid Dampness

Humidifiers are effective, sometimes too effective. It’s essential to check the surrounding area for signs of dampness or excessive moisture. If the humidifier is set on a high setting, it could cause mold and bacterial growth in the tank and around it.

To avoid this potential issue, turn the device down or off as soon as you feel like the air is at a comfortable humidity level.

4. Store Properly

If you only use your humidifier during dry seasons, such as winter, it’s important to store it properly. Before packing it away, make sure you empty the tank completely and do a basic clean. Wipe the tank and frame with a clean towel to remove any excess moisture.

In addition, when you take it out of storage, give it a quick clean as well to ensure there are no impurities.

5. Replace When Needed

It might be hard to say goodbye to a trusted appliance, but it’s definitely necessary. An old humidifier might begin to break down if it’s been used a lot over the years. In addition, worn-out parts are more likely to have a significant amount of bacterial growth.


How Can I Remove Calcium Build-Up From the Humidifier?

Calcium build-up is a common issue in humidifiers. It’s caused by the minerals found in your tap water. Homeowners living in hard water areas might experience this issue more often. Removing calcium build-up is relatively easy and can be done using plain white vinegar.

Can the Filter Air Dry By the Following Day?

The filter should be completely dry before placing it back into the humidifier. If you can spare a day without your humidifier, letting it air dry is an excellent idea to further remove any bacteria.

Can I Wash Any Part of the Humidifier in a Dishwasher?

Any electrical parts of a humidifier should never be washed in a dishwasher. Still, some humidifiers do contain certain parts that are dishwasher-safe. However, unless stated by the manufacturer, we do not recommend that you wash your humidifier in the dishwasher.

Should the Filter Be in Place When Running the Humidifier With Vinegar?

No, it’s important to remove the filter before running the vinegar solution for an hour. Any cleaner or chemical — even a natural ingredient such as vinegar — will permanently damage the filter.

What If My Humidifier Wasn’t Cleaned Before Storage?

Before you throw your humidifier out, give it a thorough clean using vinegar. However, if it looks filthy and has a bad smell to it after cleaning it thoroughly, consider replacing the unit.

What Is the Colored Residue on the Inside of the Humidifier?

If you notice any form of discoloration or residue on the inside of the humidifier, it’s likely a type of mold. Mold comes in a range of species and can be a variety of colors ranging from black to pink. If you do notice mold, disinfecting the humidifier is crucial (2).

Mold in the tank can spread to the air as the humidifier is running. This can cause you to inhale the mold or cause it to spread within your home.

Keeping It Clean

Keeping your humidifier clean is crucial to avoid mold, bacteria and other contaminants. In addition, proper maintenance will help to keep your humidifier running for longer.

Cleaning the humidifier is easy and doesn’t require any specific cleaners or tools. Depending on how filthy your humidifier is, you can either do a basic clean or disinfecting.

Vinegar is one of the best things to use when cleaning your humidifier. Whether it requires a quick clean or a more thorough job, we recommend you use vinegar.

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About the Author

Matthew Sullivan

Matthew is a freelance writer with several years of experience in DIY and HVAC. For as long as he can remember, Matthew has always found great pleasure in taking things apart and learning how to put them back together.