Do Humidifiers Cause Mold and Excessive Humidity?

Humidifiers are intended to put moisture into the air. It’s heaven-sent during winter when the air gets very dry. Unfortunately, such dry air can irritate the lungs, eyes, lips, skin, and nose – problems that humidifiers can easily fix. Despite the benefits, many homeowners are asking: do humidifiers cause mold? If not used properly, this beneficial device can have an ugly side.

Below, we discuss how humidifiers can cause a mold problem and how you can prevent it from happening.

Will my humidifier cause mold?

Anything excessive isn’t healthy, and this is quite true with humidifiers. If not used properly, humidifiers can cause mold, which is harmful to your family’s health.

Unfortunately, many homeowners run humidifiers without regulating their moisture levels. It can easily raise relative humidity levels above 55%, which is ideal for mold growth.

Beware of cold mist humidifiers!

Cold mist humidifiers are the leading cause of mold growth indoors. It boils down to this device’s mechanism.

Unlike other humidifiers, cold mist types spew water molecules into the air. This means that any organism inside the device will also be spitted out.

Overall, warm mist humidifiers are much better, but it doesn’t mean they can’t trigger molds. Once the mist cools down, it can cling to surfaces and give way to microbes. Still, it reduces the risk of a massive mold problem.

Humidifiers with no humidistats are common culprits.

Portable humidifiers are also likely to cause excessive humidity indoors. This is because portable humidifiers don’t have humidistats that will regulate the room’s humidity level.

However, many humidifiers with built-in humidistats aren’t always accurate, especially cheap ones. Most of them are off by as much as 20%, which makes homes vulnerable to mold growth.

You should also be careful in using furnace humidifiers as this can trigger a massive mold problem.

Failure to clean the humidifier can cause molds.

Aside from excessive moisture production, a dirty humidifier can also be the culprit to molds. This allows microorganisms and molds to thrive in the water container inside. When that happens, a humidifier becomes a mold-dispersing device.

It only takes a matter of weeks for the mold to start spreading all over your home. For molds that can grow in low humidity levels, the spread would be much faster.

Take note that some mold subspecies thrive in warm temperatures. So even if the indoor air is warm, molds can still grow inside.

Signs that your humidifier is causing molds

Humidifiers aren’t the sole cause of molds indoors. Still, the following are signs that your humidifier is triggering a mold problem:

do humidifiers cause mold - photo of molds

⚠️Odd smell

Any musty or unusual smell emanating from your humidifier is a sign of mold. Even if it’s not mold, you should still check and clean your humidifier. The odor-causing microbe can still trigger respiratory problems if left untouched for too long.

⚠️Recurring respiratory problems

Is your nose getting runny and itchy when staying inside the room where the humidifier is located? If so, molds might be everywhere. The effect will be much worse if you have asthma and lung problems. This is why you should consider recurring respiratory issues as a potential sign of molds.

⚠️Discoloration on surfaces near the humidifier

Another tell-tale sign of molds is a dark discoloration near the areas where the humidifier is placed. These dark or colored spots are mold itself. However, you shouldn’t try to wipe it off abruptly, as the mold spores will go airborne.

To check if it’s indeed molds, apply a drop of bleach on the spot. If it lightens within a minute, it’s likely mold growth. Also, if the discoloration spreads, it’s a tell-tale sign of a mold infestation.

Take that there’s also the so-called pink mold, which can be caused by your humidifier.

How to clean molds in a humidifier

Proper cleanup is necessary if you discover that your humidifier has molds. This is to prevent molds from spreading in your home.

Here are a few simple steps you can take:

  • Unplug the unit and take it to the sink.
  • Open the humidifier and drain the remaining water.
  • Pour a mixture of hot water and vinegar into the humidifier.
  • Next, use an old toothbrush to scrub off the water container to dislodge the molds. If there is mineral buildup, you can use fine steel wool.
  • After that, rinse the humidifier container with hot water.
  • Let it dry before reassembling and using it again.

Take note that if the humidifier has molds inside, there’s a chance that molds are already present in your home. It’s best to dehumidify the area if your home’s walls, ceiling, and floor feel damp. And if the mold is already massive, you should call a mold remediation service to handle the problem.

How to prevent humidifiers from causing mold

Preventing mold due to humidifiers is fairly easy. The following hacks are some of the easy ways to avoid the problem:

✔️Add a drop of tea tree oil.

photo of a wall with molds

A drop of tea tree oil helps prevent molds inside the humidifier. It will also give off a nice scent in your room, which can aid those with asthma and other respiratory problems. Just make sure that you’re using organic tea tree oil without any additives.

However, if you have pets at home, it’s best to consult their veterinarian first. Tea tree oil can be toxic to cats and dogs when diffused. Still, it can be diluted to prevent adverse reactions.

✔️Use hydrogen peroxide

If you’re worried about your pets, you can use hydrogen peroxide instead. This substance will kill any microbes in the solution in your humidifier. It’s also safe and won’t give off any smell. Overall, two to three drops of hydrogen peroxide are enough for most portable humidifiers.

✔️Purchase humidifier tablets

If you want a foolproof way to kill molds, you can use humidifier tablets. These are formulated to neutralize mold and prevent mineral buildup. One tablet is enough to protect the humidifier’s reservoir from molds. However, continuous use can bleach the humidifier’s hose.

✔️Clean it regularly

Whatever you choose to add to your humidifier, it’s important that you clean the water reservoir or container first. Cleaning the humidifier once a week is the rule of thumb. You can also clean it more frequently if you’re running the device for extended periods.

Just make sure you let the humidifier dry before plugging it in. Most of all, you should avoid soaking electronic parts in water.

✔️Change the filters

There are humidifier models that come with filters. Just like your air conditioner, you should clean or replace the filter in your humidifier.

Overall, humidifier filters need to be replaced every three months. I also recommend a replacement after winter because humidifiers are highly used during this season.

For filterless humidifiers, regular cleaning would be enough to keep molds at bay.

✔️Use distilled water

Minerals from tap water can cause the formation of scales, which is the breeding ground of molds. When left unchecked, the mold spores will be dispersed into the air, which can lead to a full-fledged mold problem in your home.

Aside from that, mineral deposits in humidifiers will also harbor the growth of other microorganisms that can be harmful to your family’s health.

✔️Control dampness in your home

It’s crucial to control the humidity and dampness in your home. Make sure that there’s no excess humidity seeping through your window, doors, or walls. You should also check your pipes for leaks that could increase the humidity level in the air.

Most of all, I recommend that you use a separate humidistat. You should do so even if your humidifier already has a built-in one. This will let you check if the built-in humidistat on the humidifier is accurate with its readings.

✔️Change your humidifier periodically.

Humidifiers aren’t designed to last for long. The rule of thumb is to replace it every two to three months if used daily. Meanwhile, premium models can last for a few years. Still, you should check it for any defects that could cause mold growth.

So when is the right time to change a humidifier? If there are mineral deposits that are hard to remove, you should consider getting a replacement. The same goes if molds keep coming back despite your efforts to clean the device regularly.

Benefits of using a humidifier

While it comes with some risks, humidifiers are beneficial in many ways. Here are some of the health benefits of running a humidifier once you followed the recommendations above:

Reducing dryness

During winter or when using an air-conditioner, the air is stripped of moisture. This can make your lips and skin dry. Also, the dry air can irritate the eyes and trigger frequent coughs.

To solve this, you can run a humidifier to restore the ideal humidity level in your home. You can also add a few drops of your favorite essential oil to make your room smell great.

Making coughs more productive

Those with dry cough will benefit from the moisture coming from a humidifier. It will provide moisture to the airways so that coughs will be more productive. A productive cough means it will be faster to clear as the phlegm is expelled easily.

Alleviating snoring

Many homeowners report that humidifiers helped them reduce snoring. This is because the moisture from the humidifier acts as lubrication in the airway to prevent the soft tissues in the mouth from bumping with each other.

When running the humidifier at night, make sure it’s placed on a stable surface away from flammable areas. Also, you should keep it away from pets and children’s reach.

Preventing wallpaper from cracking

With the right humidity level, humidifiers can also prevent wallpapers from cracking easily. This is very helpful during the winter months when the air is too dry. Aside from that, humidifiers prevent static electricity from building up in the air.

Helping unclog babies’ nasal passages

Humidifiers designed for babies will help keep infants’ nasal passages moisturized. These humidifiers will prevent the skin from breaking and bleeding, which is a painful experience for newborns.

However, make sure that you use the humidifier right. Also, never use hot mist types as this can scald your baby’s skin. Also, you should clean the device often to prevent molds and the presence of bacteria.

Lastly, you should place the humidifier away from your baby’s crib. It’s also important to use an oscillating fan to make sure that the air isn’t stagnant.

Frequently Asked Questions

Q: Where should a humidifier be placed?

A: A humidifier should be placed a few feet away from your bed, chair, and other spots where people stay. Make sure you keep humidifiers away from items that can burn easily. Most of all, you should keep it away from pets and children.

Q: Do humidifiers make your room wet?

A: If you don’t use your humidifier properly, it can make your room too damp. This will lead to mold growth and a slew of respiratory issues. Also, you should avoid overusing humidifiers, especially during summer.

Q: What’s the black stuff in my humidifier?

A: Black stuff on humidifiers is often a sign of mold growth. It can also be a sign of mineral buildup if you’re not using distilled water. Whatever it is, you should clean your humidifier regularly.

Q: Should a humidifier run all night?

A: Humidifiers can be used overnight, but make sure that it’s placed in a safe spot. Running the device overnight can help a lot for those who always get chapped lips or dry skin. The humidifier can also reduce the drying effect of air conditioners.

Q: Can you run white vinegar in a humidifier?

A: It’s not a good idea to run vinegar in a humidifier, especially on cool mist types. The white vinegar molecules can irritate your eyes and nose. It’s best to use vinegar in cleaning and disinfecting the humidifier. After that, it should be rinsed well before use.

Final words

Do humidifiers cause mold growth? Yes, especially if you fail to clean the humidifier regularly and properly. You should also monitor the humidity level in your room to ensure that you’re not overusing the humidifier. Overall, molds related to humidifiers are easy to avoid with regular checks. You should also consider replacing your unit if it’s been around for years.

Have you ever encountered molds in your humidifier? How did you deal with it? Share it with us below!