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Why Does My Humidifier Smell? 5 Causes & What To Do

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Humidifiers can be essential comfort tools in any home. Unfortunately, they can also be quite disgusting, explaining why today you’ve been left wondering, “Why does my humidifier smell?”

Without the regular cleaning and maintenance it requires, your humidifier will quickly transform into a vicious, festering cesspool of mold and bacteria. None of these entail the kind of stuff you’d want to be breathing in.

Fortunately for you, maintaining your humidifier is relatively easy if you do it consistently. As a general rule of thumb, most manufacturers recommend cleaning your humidifier at least once a week.

With that in mind, let’s take a look at several reasons your humidifier might be smelling as well as several ways to rectify the situation and get it back on track.

Why Does My Humidifier Smell 1
I have a cool mist humidifier that smells like algae – via Reddit

Why Does My Humidifier Smell?

Does your Humidifier Have an Electrical Burning Smell/

Burning smells aren’t the same. For example, electrical burns smell more like fish. With that in mind, if this is the kind of smell you’re noticing coming out of your humidifier, it implies that the electrical components inside your humidifier have probably burned up.

Speaking from experience, the most probable culprit inside the humidifier will be the blower motor that has overheated. This usually happens when there is a huge dirt buildup inside the blower motor.

Another probable cause of a humidifier’s electrical burning smell is faulty wiring. Of course, this will be a factory defect, and if your humidifier is still under warranty, you can have it replaced at no extra cost to you. If the unit isn’t under warranty, find a repair shop in the neighborhood and see if they can rectify the wiring.

To conclude this first reason, you’ll need to inspect the heat exchanger of your humidifier to check whether or not it has cracked.

If the whole of the humidifier has broken, expect an even more intense nasty smell in your home. It could also cause gases like carbon dioxide to leak into your home, which can, in turn, potentially endanger the wellness of you and your family members.

This brings me to my next point.

Is Your Humidifier Just Overheating?

When you notice your humidifier smelling, the first course of action should be to ascertain where the smell is coming from. If it’s a burning smell and its coming from the electric cord, then the cord in question could be faulty. Smell the cord itself to confirm this.

If you notice that the burning smell is coming from the humidifier’s base, chances are the appliance is just becoming too hot than recommended. They usually do this if they are overheating. If an overheating humidifier is left plugged in for an extended period, it could cause a fire hazard.

Note, though, that overheating can never cause your humidifier unit to explode.

Does It Have Water Inside?

Depending on your cool mist or warm mist humidifier, the chances are that you have to unplug it from the power when it starts smelling like its burning. This is particularly true for small humidifiers that do not retail with the automatic on/off features for when the water inside is all used up.

Is Your Humidifier Smelling Musty?

None of us want to deal with humidifiers producing musty smells. If you notice your humidifier emits such a smell, mold has accumulated in the humidifier. As such, to get rid of the musty smell, you’ll need to clean the humidifier using vinegar to get rid of the mold.

Note that mold also qualifies as an indoor allergen. So, if you do not get rid of it immediately before it accumulates beyond certain levels, it may cause humidifier sickness symptoms among your family members.

While researching for this detailed guide, I also came across lots of people claiming that their humidifiers smelt like wet dogs. If this happens to yours, the sulfur smell could be coming from the humidifier due to mildew or mold. Still, you’ll need to thoroughly clean the humidifier to rectify the situation.

Is Your Humidifier New?

Sometimes a humidifier will smell because it’s new. This is usually because of the plastic and chemical smell. Unfortunately, there isn’t much you can do about this. Simply give it some time, and after a few days of daily use, the smell should disappear.

Safe Practices To Keep Your Humidifier From Smelling

No matter where you source the water you use in the humidifier, chances are it’ll have some microbes that can eventually develop into a biofilm. So, if you usually turn off your humidifier for a day once a week, do not leave the water just sitting in there.

Pour it out and let the tank dry out for at least 30 minutes before refilling. You’re recommended not to refill the humidifier until you’re ready to use it again.

If like me, you tend to run your humidifier until its tank is empty, you’re still required to perform manual emptying at least once a week. Also, adding bacteriostatic treatments to the tank every time you fill-up the tank can help discourage the buildup of any nasty little organisms.

How Long Should Cleaning A Humidifier Take?

Plus drying time, cleaning a humidifier should take approx. 25 to 30 minutes each week. If you tend to let your humidifier sit for a month or more before disinfecting and deep cleaning it, expect to dedicate up to one hour to the cleaning session. The hour-long session also includes a lot of drying and soaking.


Final Thoughts

Over a long period of use, humidifiers tend to pick up odors due to mildew, bacteria, or just stagnant water. Use the tips I’ve shared above to get your humidifier smelling great again. What’s more?

Next time you’re out for a new humidifier, go for one with a humidistat and an automatic turn on/off feature (just to be safe.) This way, if the humidifier runs out of water, it’ll turn itself off automatically.