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Cool Mist Humidifier vs Warm Mist Humidifier: Which is Better?

A home with properly-balanced humidity is more comfortable and healthy. With proper humidity levels, you and your family will breathe easier and avoid many of the problems that come from air that is either too dry or too humid.

If you are trying to choose a humidifier, you’ll find that you really have two options. You can choose a cool-mist or a warm-mist humidifier. While the result is the same (moisture added to the air) the way these two types of humidifiers operate can differ greatly. For this reason, it helps to understand the differences, and, depending on your circumstances, which one is right for you.

Why Use a Humidifier?

A comparison of cool-mist vs warm-mist humidifiers would be hard to justify (let alone comprehend) if we didn’t understand the importance and usefulness of the humidifiers themselves, regardless of temperatures. Humidifiers are excellent appliances to have in the home, as they can be helpful for both overall health and for the maintenance and upkeep of the house.

Dry air inside the home can be disruptive to health, especially when you consider its effect on your nasal passages. Whether sinus problems are initially caused by the flu or allergies, dry air can exacerbate the issue, making it harder for someone to recover when they are sick.

Dry air leads to more inflammation, which further causes coughing, sneezing, itching, and even a burning sensation, but moist air can relieve many of these aggravating symptoms. Humidifiers are also popular for allergy sufferers because they tend to reduce symptoms. According to the Mayo Clinic, moisture in the air is beneficial for alleviating dry sinuses, bloody noses, cracked lips, dry skin, and many other problems caused by dry air.

The right amount of moisture in your home’s air can also impact viruses. It’s believed that ideal humidity levels will reduce (but not prevent) the chances of viruses growing and thriving in your home’s air.

Low relative humidity can increase the spread of viruses, so keeping a humidifier could improve your family’s overall health, especially during cold and flu seasons.


cool mist humidifier

Understanding Humidifiers: The Different Types

Cool-Mist Humidifiers: Evaporative vs Ultrasonic

In most cases, you will find that cool mist humidifiers come in two types: evaporative and ultrasonic. Both of these humidifiers expel a cool mist of moisture, increasing the humidity in the room, but they accomplish this goal in two different ways.

An evaporative humidifier is usually a more simplified machine. They basically consist of three parts: a fan, a wick, and a water reservoir. The wick draws air from the water reservoir and when the fan is activated, it moves air across the wick; this air picks up the moisture on its way out and, in this way, the evaporative humidifier, also known as a wick humidifier, is able to add moisture to the air.

Ultrasonic humidifiers, however, work in a slightly different fashion. These humidifiers have a metal plate that vibrates at an ultrasonic frequency. The vibrations are so powerful that they literally break apart water molecules inside the reservoir; when the molecules split, they become cool vapor, which is then emitted into the atmosphere as an invisible mist.

Ultrasonic humidifiers are popular because they are quiet and more efficient than evaporative humidifiers. (The fan in the evaporative versions can be louder.) However, ultrasonic humidifiers can produce a white dust, which is essentially leftover minerals from the water in the reservoir. You can use cleaner water such as distilled water, but it’s virtually impossible to have 100% pure water.

While these two types of humidifiers are different, for the sake of this article we will be lumping them together, giving you information (including pros and cons) that generally apply to both types of cool-mist humidifiers.


Warm-Mist Humidifiers

Warm-mist humidifiers work in a very different way. These units have an internal heating element that boils water from a reservoir and releases it into the outside air. It releases a warm mist. The units do not have internal fans, as the heating process creates enough energy to release the moisture outward.

Most warm-mist humidifiers have an internal heating element that boils water inside the humidifier. This process then creates a steam, and this steam is released outward. Some of the units also have absorption pads, which act as filters that trap minerals in the water and keep them from being released into the air and becoming dust.

Pros and Cons of Cool Mist Humidifiers

Pros of Cool-Mist Humidifiers

Because of how they operate, cool mist humidifiers generally require less electricity than warm mist units, making them more efficient and reducing your expenses in an energy bill.

Also, while warm-mist units are generally safe, cool-mist humidifiers do not have hot components that can cause injury; this is especially important if you have small children in the home.

In fact, the Mayo Clinic recommends that parents only use cool-mist humidifiers for children. The hot water or steam from a warm-mist humidifier can be harmful to children and can cause burns if someone gets too close. A child (or careless adult) could also knock over the humidifier, causing injury. For this reason, people concerned with the overall safety of a home will want to choose a cool mist humidifier.

When it comes to initial price, you will likely find that cool-mist humidifiers are usually more affordable as well, and they can often be purchased in sizes that are more manageable and portable.

Many cool-mist humidifiers use filters to remove contaminants from the water and mist. These filters can capture bacteria and viruses, preventing further growth. Warm-mist humidifiers, which use heat, tend to kill many of the organisms in the water, so filtration is not as important. Filters can also capture the minerals in water, keeping them from creating dust when they settle.

Generally you will find that evaporative humidifiers have filters, but ultrasonic humidifiers do not, which is why they can create more dust. Changing these filters on a regular basis is important for the performance and effectiveness of the units.


Cons of Cool-Mist Humidifiers

One of the major setbacks for cool-mist humidifiers is the increased chance for mold spore production and bacteria. For this reason, you need to clean the units thoroughly, which means overall ownership can be more of a hassle.

Many cool-mist humidifiers also have a filter that needs to be replaced on a regular basis; this is not a difficult task, but it will take time; if you forget, it can harm the overall performance of your humidifier.


warm mist humidifier in home

Understanding Warm Mist Humidifiers

Pros of Warm Mist Humidifiers

One of the main advantages for warm mist humidifiers is that they are generally much quieter than cool mist humidifiers. The cool mist units have fans that blow the mist into the air; just like a house fan, this can create a lot of noise, which some homeowners may find annoying. If you want to keep the home quieter, consider a warm-mist humidifier that does not have a fan.

Another advantage of a warm-mist humidifier, although it is admittedly slight, is that they can help warm a room. During the cold seasons, keeping a room warm could be difficult, but a warm-mist humidifier could not only add moisture to the air (which is important during the winter) but also keeps the room’s temperature more comfortable. You can’t rely on the warm mist as a space heater, but it does help, although only slightly.


Cons of Warm Mist Humidifiers

The biggest disadvantage for using a warm mist humidifier is the potential safety concern. These units can get hot, and parents will want to make sure that children are not able to touch the humidifier, as contact with certain components can lead to burns. If you use a warm-mist humidifier in a home with children, you will need to be extremely diligent to ensure that the children do not have access to the unit.

Warm mist humidifiers also use more electricity than cool-mist units. This is because it takes more energy to heat the water than to operate a fan or the ultrasonic plate. While the difference may not result in a huge utility bill, if you are concerned with energy use you may want to have a cool-mist humidifier instead.

Warm-mist humidifiers can also lead to issues with dust from the water, which is why many people prefer distilled water for these units.

Warm or Cool, Cleaning Remains Essential

Whether you use a cool-mist or a warm-mist humidifier, proper cleaning remains essential. Because humidifiers have a reservoir of water, they can easily have mold and bacteria growth, which could be spread through the mist. For this reason, it is absolutely essential that you take your time and clean the units thoroughly.

Proper cleaning will depend on the unit, and you should be able to find cleaning instructions in the owner’s manual. If your unit did not include cleaning instructions, you can likely find information from the manufacturer online.

No matter what the appliance, cleaning will require that you wash and rinse the water reservoir, remove accumulated dust, and sanitize the unit on a regular basis. Some experts recommend filling the tank with water and mixing in a tablespoon of bleach, which will kill the bacteria. You can also use white vinegar to remove many of the contaminants.

Add Qualify Air Purifiers to Your Space

In addition to maintaining a good relative humidity level in your home you can also benefit from clean, fresh air for your overall indoor air quality. Oransi has the right air purifiers to keep your home full of healthy air to help you get a better night's sleep. Browse our full selection and you’ll find the right options for living rooms, bedrooms, and even commercial spaces.

With the right air purifier, you’ll breath air with less pollutants and fewer allergens, so contact our staff today for more information!