How to Clean a Humidifier and Thoroughly Disinfect It

How-To Guides
by How-To Guides

There’s nothing more soothing than a humidifier in the parched winter air. There are innumerable benefits of running a humidifier: You’ll have softer skin, moist nasal passages, relief from coughs, and your tropical plants will benefit, as well.

But if you’re an owner of this appliance, you need to know how to clean a humidifier correctly so it doesn’t become a magnet for germs, mold, and mildew.

Our guide gives you the best ways to clean a humidifier so you can make sure it emits the cleanest, freshest mist to make your home healthy and comfortable.


Photo via Shutterstock

Why You Should Clean Your Humidifier

In addition to painful dry lips and skin, a home without humidity can also cause cracks, gaps, and other damage on wood floors, furniture, and even in electronics.

All the benefits of a humidifier can become undone if it’s dirty. A dirty humidifier filled with bacteria and mold can send spores out into the air you breathe.

As a result, anyone can potentially experience the following from a dirty humidifier:

  • Asthma attacks
  • Severe coughs
  • Lung inflammation or scarring
  • Fevers
  • Loss of appetite
  • Anxiety
  • Shortness of breath

A dirty unit will also begin to emit a nasty odor and can start to fail to work effectively, since the filter will be damaged by all the build-up, according to Honeywell, makers of humidifiers. Those are all pretty solid reasons why you should clean your humidifier.

Why a Humidifier Gets Dirty

Let’s dive in a bit deeper to see why your humidifier gets so dirty. The water you use in your humidifier can cause your appliance to become crusty and dirty, according to WebMD. It may not matter if you use tap or distilled water—both have minerals that can clog your humidifier which causes more bacteria to grow inside the machine.

Using distilled water in your humidifier will cut down on mineral build-up. Distilled water may have minerals, but it has less than tap water, especially hard tap water.

How Often to Clean a Humidifier

It’s best to do a deeper cleaning on your humidifier once a week, regardless of what type of appliance you have. That way, you can eliminate mineral buildup before it becomes a serious issue. However, it’s best to disinfect your humidifier once a month, which is a different process than deep cleaning (which we will get to below).

How You Know It’s Time to Clean a Humidifier

If you haven’t been keeping up with weekly maintenance, there are three tell-tale signs that will let you know you need to clean your humidifier:

  1. You may begin to smell a bad odor coming from your humidifier. 
  2. You may begin to see mold spores form on the inside of the humidifier’s water reservoir. 
  3. The walls inside of the reservoir or base of your humidifier seem greasy or grimy. If this happens, your machine really needs a deep clean.
How to Clean a Humidifier With Vinegar

How to Clean a Humidifier With Vinegar

Any distilled white vinegar is considered a superior cleaning ingredient that cuts through grease and grime. But when cleaning a humidifier, opt for what’s called “cleaning vinegar” with six percent acidity (cooking vinegar has five percent acidity).

Don’t cook with cleaning vinegar, though! That extra one percent will make the vinegar 20 percent stronger in its ability to clean, so stick the jug of six percent vinegar in your cleaning cabinet, not your pantry!

Use vinegar to clean the appliance, but be sure to never run the humidifier with vinegar in it. A mist of vinegar in the air can irritate your eyes, nose, throat, and lungs.

Disclaimer: Hometalk may receive a small affiliate commission from purchases made via Amazon links in this article but at no cost to you.

Tools and Materials Needed:

  • White cleaning vinegar (six percent acidity—this is not the same as cooking vinegar)
  • Clean cloths
  • Soft old toothbrush
  • Bowl

Step 1: Unplug the Humidifier

Unplug and empty any water in the humidifier’s tank. Be careful not to get any water on the electrical components of the machine.

Step 2: Fill Base With Vinegar

Fill the base of the humidifier with one cup of hot water and one cup of white vinegar. Let it sit for one hour.

Step 3: Clean the Reservoir

Remove the build-up of the greasy film from stagnant water by filling the reservoir with two cups of white vinegar. Seal it shut and shake it for a minute or so to loosen grime.

Step 4: Empty Reservoir

Let the vinegar filter out into a sink through the reservoir nozzle. 

Step 5: Scrub Away Build-Up

If you see any mineral build-up—white stains or a film) in the reservoir or the base, use a soft toothbrush dipped in vinegar to remove the minerals.

Step 6: Rinse Reservoir

Rinse the reservoir with plain water.

Step 7: Rinse Base

Pour the solution from the base into a sink and wipe the base down with a clean cloth soaked with white cleaning vinegar. Let air dry.

Step 8: Clean the Nozzle

If the nozzle is detachable, soak it in a bowl of hot water and vinegar for 10 minutes, then rinse.

Step 9: Wipe the Exterior

Use a clean, white cleaning vinegar-soaked cloth to clean any funnels and the outside of the machine.

How to Disinfect a Humidifier With Hydrogen Peroxide

How to Disinfect a Humidifier With Hydrogen Peroxide

Vinegar will clean your humidifier of grime, but it won’t disinfect it. That’s where hydrogen peroxide comes in for that once-a-month disinfecting task.

Don't Use Bleach

Most appliance manufacturers will strongly discourage you from cleaning humidifiers with bleach. You don’t want to inhale mist with bleach in it.

Tools and Materials Needed:

  • Hydrogen peroxide (three percent)
  • Bowl

Step 1: Mix the Solution

Combine four parts water with one part hydrogen peroxide and mix well in a bowl.

Step 2: Fill Tank

Pour the solution into the humidifier tank. Leave to soak for a minimum of 30 minutes.

Step 3: Empty and Rinse

Empty the tank of the solution and rinse it with clear, clean water.

Step 4: Air Dry

Let the tank completely air dry before reassembling.

How to Keep a Humidifier Clean

In addition to weekly cleaning, here are a few other tips on keeping your humidifier clean as a whistle:

  • If you run your humidifier daily build it into your daily schedule to empty, rinse, and dry the base and tank.
  • Check the humidifier’s filter for deposits: Loosen any visible scale on a hardened filter by soaking the filter in cool water, but check your humidifier’s owner’s manual for confirmation. Never twist or squeeze the filter when cleaning.
  • Replace any filters and cartridges per the owner’s manual. A filter might need to be replaced every 30 to 60 days.
  • Clean and disinfect your humidifier when you put it away for the season and when you bring it out for use for the season.
  • Add a few drops of tea tree oil to the reservoir and run the humidifier; it has antibacterial, antiviral, and anti-fungal properties, helping you breathe better while inhibiting the growth of mold.

How to Clean a Humidifier

Do you have tips on products or methods you’ve used to clean a humidifier? Has your humidifier been able to give you a better quality of life? Please share your ideas and experiences below with the Hometalk community!

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 1 comment
  • Gig69451122 Gig69451122 on Aug 31, 2023

    I have a portable one. What I've done? Was the vinegar add. But, I placed it outside on the deck, on a clear day. Plugged it in, & let every part get steamed out. I found this worked well too.