You are currently viewing Ultrasonic vs Evaporative Humidifier

Ultrasonic vs Evaporative Humidifier

You might have been contemplating to get a humidifier for your home. However, you might wonder what the difference is between an ultrasonic humidifier and an evaporative humidifier. Fortunately, we are here to help you.


In this guide, we will explain the differences between these two humidifiers. Hopefully, by the end of it, you will be able to make an informed decision.

What is a Humidifier?

A humidifier is a gadget that ensures that moisture levels in a home or work environment are maintained by increasing the level of humidity, especially during the cold season. Humidifiers can either be used to humidify one room or an entire building, depending on a person’s preference.


In buildings like hospitals, they are used to make the environment more comfortable for patients. There are different types of humidifiers, with two of the most common types being the evaporative and ultrasonic humidifiers.

Evaporative Humidifier

Between the two, an evaporative humidifier has a simpler design and is more manageable. Having various designs, some have filters while others do not, but most have a wick, fan and a reservoir.

The main function of an evaporative humidifier is to release moisture into the air. Thus, reducing the dry air, which can irritate the skin and the throat when inhaled. Furthermore, it also reduces the durability of items present in the house, such as wooden chairs and floorboards, among others.

This humidifier works in a circular motion, starting from one particular point and repeating the same process all over again. Dry air in a room is sucked into the device by the rotating fan. Within the humidifiers’ casing is where the wick is located.

Smoke Humidifier Led Color Mood Light

The wick filter absorbs water from the humidifiers’ water reservoir. Then, this water is absorbed by the air as it passes through. The air is then released back into the atmosphere in the room in form of a spray or water mist.

The level of humidity in the room determines how much of the water from the wick will be absorbed by the humidifier and then released. In an instance where the room is already humidified with enough moisture, there is no evaporation.

This is because the evaporative humidifier recognizes that there is already high humidity and no moisture is released. Moreover, the filter design is good at trapping dust, which helps in the release of clean air into a room.

Kinds of Evaporative Humidifiers

There are two different kinds of evaporative humidifiers that you have to take note of.

  1. The first type is one that has filters that are porous. For this type, it might be more inconvenient when it comes to cleaning and maintenance, since it can easily get polluted by many different factors.
  2. On the other hand, the second type has rotating discs. Unlike the first type with porous filters, this one is much easier to clean and take care of. This is because of the fact that it is made out of plastic that has been hardened.

Ultrasonic Humidifier

An ultrasonic humidifier makes use of vibrations instead of the wick and fan found in evaporative humidifiers. Made up of a tiny metal plate, the plate emits a high ultrasonic frequency. Once it vibrates, it splits water molecules within the water reservoir, changing them into water vapor.

The water vapor is then released into the atmosphere, balancing the humidity levels. Due to the lack of hot water in the water reservoir, the ultrasonic humidifier reduces any chances of blistering. In fact, it is considered by some to be safer than the evaporative humidifier.


Although it doesn’t produce any sound like the former, the ultrasonic humidifier does not have a filter. This results in the formation of gray dust into the room. These dust particles will be explained more further on.

One of the options used to reduce these emissions is to purchase models that have ceramic-type cartridges, which can be replaced once in a while, disinfecting the humidifier. On the other hand, use demineralized water, which releases fewer mineral deposits into the air.

However, the use of demineralized water can be costly.

Price Difference

As mentioned, there are different types of humidifiers that are available and they have varying prices. However, it depends on the type that you choose to purchase as well as their operational functionalities.

That said, you are able to either get evaporative or ultrasonic humidifiers at reasonable costs, which are economically-friendly, fitting into your budget. Although ultrasonic humidifiers are normally higher in cost compared to evaporative humidifiers.

Like most things these days, those that have the lowest features are normally cheaper, with ultrasonic humidifiers ranging from low end priced ones, to those that are pricey.


Ultrasonic humidifiers that have more than one function, such as those that release both cold and warm mist, are costly. These models can be used during different weather conditions, which involve the cold mist during warm weather, or in hot climatic conditions.

On the other hand, the warm mist can be released during winter or cold weather. Other extra features that might make the ultrasound humidifier cost higher than the usual price include features like automatic functioning, which can be found in some.

While evaporative humidifiers might seem cheaper, their maintenance is a bit difficult and its costs increase with time, taking into consideration the frequent need to exchange filters and the wick. That said, the wick should either be replaced or washed from time to time.

You are able to get wicks and filters for replacement at different prices, depending on the size. However, although they are not expensive, the regular replacements will definitely build up your costs with time.

Health Risks

As mentioned, humidifiers work by increasing the moisture i.e. humidity in the air. However, one purpose for this is in order to prevent dryness that can result in irritation, or itchiness on parts of the body.

Not only that, humidifier therapy is particularly useful for treating nosebleeds, sinus irritation and dry throats. While a humidifier may have plenty of benefits, users should also note that both the ultrasonic and evaporative humidifiers have different advantages and different side effects.


One advantage of the evaporative humidifier is the fact that it makes use of a filter, which allows it to significantly reduce the presence of dust particles. While dust particles may be a mere annoyance to some people, they are in fact quite dangerous.

This is because they can trigger an asthma attack or allergic reaction in some people. However, you have to take note that the filters on evaporative humidifiers need to be changed on a regular basis in order to be effective.

On the other hand, as mentioned previously, ultrasonic humidifiers eliminate the dangers of scalding from hot water, which makes them slightly safer to use. However, as ultrasonic humidifiers lack a filter of any kind, this can result in an increased buildup of gray dust particles in the air.

These gray dust particles are a result of mineral deposits from the water being left behind. The dust particles are harmless to most people, but can be dangerous if exposed to asthma sufferers or young children.


If you are living in a location where the water is particularly “hard” i.e. water that has a high mineral content, chances are that an ultrasonic humidifier can result in a dustier environment.

Along with this, there is an increased risk of bacterial contamination as well, as the water is not heated. This means that users need to ensure that only clean water is being used at all times.

Noise Difference

Humidifiers are most commonly found in the bedroom, where it can help you get a good night’s rest. Instead of waking up with a sore, dry throat, or a bleeding nose, the moist air can bring relief from such ailments.

Along with this, humidifiers also help eliminate snoring, as the nasal passages are kept moist.

In this regard, ultrasonic humidifiers are much more popular with users, as they are almost noiseless in operation.

Diffuser Aromatherapy Aroma Oil Essential Oils

This is because, as mentioned, they do not make use of a fan system, which is especially beneficial if you are a light sleeper. On the other hand, the more traditional evaporative humidifier emits a noise, which can be irritating for light sleepers out there.

If you are a heavy sleeper who is not bothered by ambient sounds, or you are looking for a humidifier for anywhere other than your bedroom, the evaporative humidifier is not a bad choice.

The Design

As discussed earlier, both ultrasonic and evaporative humidifiers operate by increasing the humidity of the surrounding air. However, the design of both these humidifiers differ significantly. Here, we look at the differences between the designs of these two humidifiers.

As we all know by now, the most common and simplest type of humidifier is the evaporative humidifier. This is because it consists of 3 primary components which we now know to be the reservoir, the wick and the fan, which disperses water into the surrounding air.

humidifier air
Image Source

On the other hand, as stated previously, an ultrasonic humidifier uses high frequency vibrations to expel an ultra-fine mist of water into the air. As a result, it doesn’t emit a humming noise. The key component in an ultrasonic humidifier is its ceramic diaphragm, which allows water to be dispersed silently.

While ultrasonic humidifiers are silent in operation and energy efficient, they do not make use of a water filtration system, which is its main drawback. This means, as previously mentioned, that you are able to expect to see more of those flecks of dust around your home.


Just like any other piece of equipment, you have to take care of your humidifier to ensure that it is in excellent working condition at all times. That being said, both evaporative and ultrasonic humidifiers have differing maintenance requirements.

In this section, we look at some of points that you need to look out for when maintaining your humidifier.

Evaporative humidifiers, being much simpler in design, have lower maintenance requirements. Periodic replacement of filter cartridges and regular cleaning and disinfecting can go a long way in ensuring the safe operation of your humidifier.

humidifier air
Image Source

Moreover, keeping your filter cartridges in check can reduce the amount of gray dust build-up. In addition to that, regular cleaning can reduce bacterial contamination and fungal growth.

On the other hand, since ultrasonic humidifiers are more advanced, they may need regular maintenance checks by a qualified technician. The ceramic diaphragm may need to be replaced after a set period of time.

However, some models come with ceramic-type filter cartridges that need regular replacement as well. Also, do take note that ultrasonic humidifiers need to be regularly cleaned and disinfected to reduce the likelihood of fungal growth and minimize the spreading of bacteria.

Possible Risks Humidifiers Pose

Despite all the benefits that humidifiers bring to our homes, there are some risks – besides the dust particles – that you have to take note of. For one thing, if the humidifier gives out too much moisture, then there’s a high possibility that it will cause mold to grow on your house.

Hence, you must always make sure that before your use a humidifier – whether it is an ultrasonic one or an evaporative one – your house needs to have good ventilation.


In areas with cold climatic conditions and colder seasons like winter, the humidity levels are usually low. Low humidity levels cause the drying out of the surrounding air, which can have severe health issues, especially in the throat and nose.

Home equipment such as furniture, walls and floors made out of wood can easily dry up, which can cause them to crack, split, or flake off. As a result, this reduces their durability due to wear and tear.


Humidifiers are essential in maintaining a comfortable environment and when used well, they ensure that the surrounding air within the room is healthy for the occupants. In other words, humidifiers provide a safe and clean atmosphere.

Moreover, they are available in different designs, models and sizes. For those looking for humidifiers for home use, you are able to purchase the small humidifiers, which are able to provide the right levels of humidity for small spaces.

On the other hand, if you would like to purchase a humidifier either for commercial use, an institution such as a medical center, or home for the aged, large humidifiers are also available. Ready to learn more? Here’s our complete review of the best humidifiers of 2018.

Melissa Styer

Melissa Styer is the Founder, and long time Editor-in-Chief of With a Bachelor of Science Degree from the University of Oregon, and a Masters Degree in Biology from California State University, Melissa has been writing and teaching about essential oils and the importance of a maintaining a healthy living environment for over 25 years. === Hi All, I started Wellness Appliances in the Winter of 2014 as a way to and share my knowledge and thoughts on essential oils and the importance of healthful living. As a youngster, I have vivid memories of walking through the large fantastic garden my dad kept for his entire life. It was there I learned about all the plants and the varied, important properties they can offer humanity. A cool morning misty walk down the meandering paths was a child’s delight, and something I still do to this day in my own sprawling gardens. While I have stepped back from the day-to-day managing of Wellness Appliances, I intend to continue contributing articles on subjects that matter to me from time to time. My days are largely filled volunteering at the local co-op, tooling in my vegetable and fragrance gardens (which I attempt to keep as a year-round gardens), writing, and being the leader of the pack to my two dogs Jacko and Lea. Thanks for the years of great readership! - Melissa

Leave a Reply