How do Cool Mist Humidifiers Work?

This article explains how cool mist humidifiers work. 

Cool mist humidifiers aren’t the most complicated things in the world to wrap your head around, but there is some stuff that needs explanation. 

I have been using a cool mist humidifier for years, and it has taken me some time, allowing me to fully understand all the ins and outs. 

But tell you what, I’ve been wholly fascinated with my discovery. Below, I’ll tell you everything you need to know about cool mist humidifiers—including their functionality and benefits— and give some cool recommendations at the end.

So, if you want to know how cool mist humidifiers work and what makes them so special, keep reading!

How a Humidifier Works

A Humidifier is perfect during colder seasons when the air gets uncomfortably dry and respiratory problems follow. But how exactly do these machines work? 

Different humidifiers use different mechanisms to moisten the air in your indoor environment and increase its humidity. 

For example, steam humidifiers boil the water in the tank and propel hot steam to moisten the air.

On the other hand, evaporative humidifiers use a fan to force air through a filter soaked in water. As the air passes through, some water evaporates, adding moisture to the atmosphere.

Lastly, ultrasonic humidifiers use a diffuser vibrating at ultrasonic frequencies to convert water into tiny droplets, producing a cool mist. That said, these humidifiers can also release warm mist if used with hot water. 

How a Cool Mist Humidifier Works

Cool mist humidifiers work either by using ultrasonic vibrations to break water into tiny droplets and diffuse them into the air or, using a fan to evaporate the water that’s been pulled up into a wick.

In both cases, they release a cool mist that increases a room’s humidity but not the temperature. Cool mist humidifiers also make an indoor space feel a little cooler. I’ve described how the three most common types of cool mist humidifiers—evaporative, ultrasonic, and impeller—function below.    

How do Evaporative Cool Humidifiers Work

An evaporative cool mist humidifier uses an internal fan to pull air into the unit. This air is passed through an absorbent wick filter, where it becomes moist. The humidifier disperses the now damp air into the room, which increases the humidity levels.

Because evaporative humidifiers do not use heat to circulate moisture, they are safe for everyone, including babies and pets. Another upside of buying an evaporative humidifier is its reasonable price tag and lower dust discharge.

However, you need to clean the wick filter regularly to preventmold and bacteria growth in the water tank.

How do Ultrasonic Cool Humidifiers Work

An ultrasonic humidifier uses a ceramic diaphragm that oscillates to create ultrasonic vibrations–turning water into tiny droplets. As the vibration frequency increases, the water droplets are propelled out of the humidifier in the form of water vapor.

This vapor is then absorbed into the air, moistening the air. Ultrasonic humidifiers are environmentally friendly, have a whisper-quiet operation, and do not pose any health risk.

How do Impeller Humidifiers Work

Impeller humidifiers use a rotating disk that flings water through a diffuser. The diffuser then breaks water into droplets–releasing them into the air as mist.

Impeller humidifiers are inexpensive and very safe to use. But because impeller humidifiers use a rotating disc, they can produce a lot of noise.

Benefits of a Cool Mist Humidifier

Now that we know how cool mist humidifiers work, it’s time to dive into how these humidifiers can benefit us. 

Relief from Nasal Dryness

One of the key benefits of a cool mist humidifier is that it helps deal with morning sickness. The increased moisture in the air clears out the nasal passages and reduces mucus clogging–soothing the throat and nasal tissues.

Cool mist humidifiers are highly recommended if you’re prone to allergies and sinus problems all year round. Sso you can get relief even during the hot, sticky weather.

Faster Recovery from Illnesses

A cool mist humidifier can help you get over illnesses quickly. With adequate moisture in the air, there will be less mucus in your nose, and your body can take in enough oxygen.

Oxygen will improve blood circulation and help you recover faster from illnesses.

Helps with Snoring and Sleeping

If you have trouble with snoring or sleeping, a cool mist humidifier may be the solution. With a humidifier running all night, the air in your room will get sufficient moisture, and your nasal passages will be congestion-free. This can improve the quality of your sleep.

Blooming Houseplants

Being a plant enthusiast, you should know that having the correct humidifier is essential for indoor plants. A cool mist humidifier can keep the moisture of a room at optimal levels.  

With enough moisture in the air, soil will not dry out as quickly, and tropical houseplants will thrive!

More Vibrant Skin

Our skin needs plenty of water to keep it hydrated. A cool mist humidifier can supply sufficient moisture in the air, improving skin health. 

Hydrated skin will absorb more nutrients and protect the skin from external pollutants. So, you can say goodbye to dry, dull skin and say hello to soft, glowing skin.

Recommendations For Cool Mist Humidifiers

Vicks Mini Cool Mist Humidifier

The Vicks Mini Cool Mist Humidifier is ideal for home use, including both adult and children’s bedrooms, as there is no risk of buns with cool mist technology.

It has a sizable 1.8-liter tank capacity that can last up to 24 hours without the need to refill. It also has a whisper-quiet motor, so you can easily enjoy a goodnight’s sleep.

Even better, it comes with an adjustable mist option that helps you reach the ideal humidity level between 40-60% and an adjustable nozzle that you can use to guide the mist.

Because of its compact design, it is effortless to use and maintain. In addition, the light and sound feature indicate when to clean your humidifier–making maintenance that  much easier.

The best part? It has two slots for VapoPads with essential oils for extra comfort when you’re  feeling under the weather. The Vicks Mini Cool Mist Humidifier is a premium-quality unit to invest in!

LEVOIT Cool Mist Humidifier

If you hate dry winter air as much as we do, the LEVOIT Cool Mist Humidifier is the perfect humidifier to add to your house. It is perfect for bedrooms, offices, and even nurseries.

It has a user-friendly top-fill design that makes refilling water a breeze. The large size also means that it lasts up to 3 nights in a row without needing a refill. 

Equipped with a  control knob and 360-degree rotatable nozzle, you can customize the volume and direction of the mist. It also has an automatic shut-off feature for when the water tank is empty, which is really convenient. 

You no longer have to worry about congestion, dry throat, and sleepless nights. The LEVOIT humidifier has a whisper-quiet motor and aromatherapy feature that helps you relax and breathe better at night.

It uses safe, BPA-free material, which makes it safe to use around babies, pets, and plants. You can’t go wrong with the LEVOIT Cool Mist Humidifier!

YOKEKON Cool Mist Humidifier

With its 2.5-gallon detachable water tank capacity and 500 square feet of area coverage, the YOKEKON Cool Mist Humidifier is a highly recommended humidifier for large-sized rooms.

It’ll operate for 36 hours straight without needing a refill. But even refilling the tank is an easy task thanks to the top-fill design. You can easily open the lid to add water without taking the whole unit apart.

It also lets you diffuse essential oils, which can be quite soothing . Even better, it has an adjustable humidistat, with three levels of humidification and a mist output of 300 millimeters per hour mist output.

This large capacity cool mist humidifier runs below 35 decibels, so you can still get a good night’s sleep if it’s running in the background. This also makes the unt perfect for use in a child’s room. 

Additionally,  it has an automatic shut-off feature, so if there’s no water in the tank, it will not run. This helps prevent damage to your humidifier and also  ensures your safety.

Wrap Up 

Cool mIst humidifiers can help combat a lot of symptoms of respiratory diseases , and if you live in a climate with very dry air, buying a cool mist humidifier is the right way to go.

I have been using a cool mist humidifier for years and it’s become an essential part of my life. Hopefully, this article has given you a head start on researchng cool mist humidifiers and finding the right one for your particular needs.


Shawn Willis is all about humidifiers. After working for some of the biggest names in the industry, he started HumidifierGuys with Scott Dawson. Now, the dynamic duo helps others figure out what they need in their next humidifier.

Shawn is an avid sports fan, motorcycle enthusiast, and has two dogs named Whiskey and Boba.