How to Keep Your Humidifier Mold-free To Avoid Sickness

Humidifiers enhance the air quality and improve the comfort of your home.

But they have some disadvantages, and one of them is that they can develop mold. In return, this can cause nasty mold exposure symptoms in babies.

If you make a habit of maintaining your humidifier properly as often as possible, it is easy to notice when something is amiss.

When you take too long between cleaning sessions, you can have a problem of mold without being aware of it. You will also find other bacteria in the humidifier.

You also need to check whether the humidifier filter is dirty. These harbor serious bacteria all the time.

Or perhaps this is your first humidifier ever. Thus, you do not know the symptoms of mold in a humidifier to check out.

Should I worry about mold in the humidifier?

Why should I worry about mold in my humidifier
Mold can also grow on whole house humidifier filter


Mold can cause a few humidifier sickness symptoms.

It is unlikely that mold in your humidifier will make you sick, but all the same, you have to be very keen.

For example, if you see signs of mold in your humidifier, it means you have not been giving it the proper care and maintenance.

Chances are there are more bacteria in the humidifier. These could cause humidifier sickness symptoms!

Mold is one of the many indoor allergens that we really would not want to have at home. It can be bad for people who are asthmatic or have a compromised immune system.

Where there is moisture, there is likely to be mold. Since a humidifier is always in contact with water, mold is going to grow unless you take deliberate steps to prevent it.

Mold could affect the performance of your humidifier. It is something that should not be in your humidifier in the first place, so be sure to keep it away.

Mold in the humidifier is not going to manifest like the gray or black mold that you usually get on the walls.

Check for red or pink mold in the humidifier.

Just know that if you have water constantly in the humidifier, mold can happen. However, there are ways to prevent that.

Start by changing the water frequently and keeping the humidifier as clean as possible.

Common symptoms of mold in a unit

Image of can humidifiers cause mold

There are not too many humidifier sickness symptoms, but there are obvious telltale signs to warn you of mold in your unit.

Here, we will look at just a couple of them:

1. A pink or gray layer on the water

This is an indication of mold in the humidifier. If the water has been in the tank for some time, you may start to see a pale pink layer on the water.

This is an indication of mold. If you see that, empty the water immediately and clean the humidifier.

An indication of mold could also be an indication of other bacteria that your family will inhale with the mist.

Whatever microorganism is in the water is going to be dispensed together with the mist, so you will breathe it in.

However, if you use a warm mist humidifier, it is going to kill all the bacteria, so it will dispense a healthy mist.

Since this small pink layer can be hard to see in humidifier tanks colored blue or other colors, you should actively look for it.

Disconnect the humidifier tank and check for any signs of mold in the water. If it has been a week or more since you changed the water, there is likely to be mold.

2. Having a hard time breathing

Mold in humidifier symptoms

If you have difficulty breathing due to humidity, it could be an indication of an ailment or other conditions. But it could also be one of the symptoms of mold.

If you have been running a humidifier full-time and someone is diagnosed with a lung-related ailment, check the humidifier.

You should let the doctor know that you use a humidifier at home. Mold exposure symptoms include breathing issues, pneumonia, and others.

They do not have to be severe; they can be mild and easy to treat. However, continued use of a humidifier with mold could cause chronic lung and breathing issues.

Please note: Wheezing and other breathing symptoms are caused by mold in your home. This is not likely to happen as a direct result of mold from the humidifier.

3. Humidifiers causing sore throat

A humidifier can cause sore throat, stuffy nasal passages, and other ailments.

If you start experiencing many cold-related symptoms, then it is time to check the humidifier for mold if you have been running it.

Some of the symptoms of mold include irritation in the throat, coughing, eye irritation, and stuffiness in the nasal passages. If you start noticing such problems, it is time to look for signs of mold in the tank.

Please note that if you are not sensitive to mold, you are not going to experience these symptoms. If you are allergic to mold, the symptoms will be more severe.

You may even experience skin irritation. Let us just say that if you start experiencing some symptoms that you have not been used to, you could check the humidifier if you have one.

If you experience these symptoms, just get away briefly from the humidifier. You know, go to a room that does not have a humidifier and check whether your body is going to react.

If you do not experience these symptoms, you can conclude that the humidifier has developed mold.

3 ways to prevent mold from growing inside humidifiers

How to prevent mold formation in a humidifier

Now that you know about the symptoms of mold in a humidifier, it is time to find out how to prevent this indoor allergen from growing in the tank.

If mold is developing inside the house or on the walls, you have to reduce the humidity. It is recommended to keep it under 45 percent. You can use a hygrometer to find out the humidity inside your home.

As for preventing mold in a humidifier, here are a few things to do:

1. Clean the humidifier regularly

Mold on the humidifier filter is common.

If you run your humidifier every day, clean it daily. Mold is a fungus or yeast that thrives in moist conditions.

When you clean the humidifier tank daily, you reduce the chances of mold developing. If you do not operate the tank daily, clean it before using it a couple or three times a week.

How to clean humidifier tank

  • Step 1: Switch it off, unplug it, and let it cool down – for your safety
  • Step 2: Remove the tank and empty it
  • Step 3: Remove the mist tube, mist nozzle, clean them in water and vinegar
  • Step 4: Pour water into the tank, about half the tank capacity, and add white vinegar to fill the tank to about three-quarters
  • Step 5: Swish the water-vinegar solution to reach all parts of the tank, pour it out and rinse tank with clean water

How to clean humidifier filter

  • Open the filter cover, and twist, pull or slide the filter out
  • Rinse the filter under warm running water to remove loose debris
  • If heavily soiled, add a few drops of dish soap and gently scrub with the provided brush
  • Rinse thoroughly with clean water to remove all soap residue.
  • Optional: Soak the filter in a solution of equal parts water and white vinegar for 30 minutes to kill bacteria and remove mineral deposits. Rinse well afterward.

2. Use vinegar in the humidifier

Add a teaspoonful or two of white vinegar to the water. That way, you make it hard for mold to develop.

Please note that adding vinegar is only important if you are using tap water in the humidifier. If you are using distilled water, there is no need to add vinegar.

When cleaning the humidifier, you can use bleach, as it kills microbes and mold. However, never use bleach and white vinegar together, as they form toxic gas.

3. Check the humidifier regularly

Only run the humidifier when necessary. Just use a hygrometer to check the level of humidity indoors. Even if you have a whole house humidifier, ensure to have it checked regularly.

Check for signs of black mold in the humidifier, which occurs in the form of black slime. Likewise, if you notice gray or pink slime in the humidifier, you have mold.

Mold in Humidifier Indications: FAQ

Here are some of the questions that most people ask frequently about how mold develops in humidifiers.

They might help you understand how to easily detect mold in a humidifier.

Can a humidifier give you pneumonia?

This is not very well known. A few studies show that some strains of mold and mildew can cause symptoms such as those you would experience when you have pneumonia.

A humidifier causing sore throat causing sore throat is possible. Check out for an escalation of sore throat.

If it disappears a few days after switching off the humidifier, you will know that it was the culprit.


Mold is a sinister indoor allergen, especially for people who are allergic to it. It can give you many breathless nights of wheezing, coughing, sneezing, and throat irritation.

Mold in the humidifier filter is serious. It can cause asthmatic attacks.

Can a humidifier cause mold in a room? Unknown to many people, humidifiers cause mold. Stay on the alert and keep checking for mold in humidifier symptoms.

Will the humidifier make you sick? As good as this appliance is, it can indeed make you sick. Watch out for humidifier sickness symptoms.