What is the difference between an ultrasonic and evaporative humidifier?

February 29, 2016 • By


The key differences between an ultrasonic humidifier and an evaporative humidifier

Humidifiers come in two main different types. These are the ultrasonic humidifier and the evaporative humidifier. Both have the same intended function and those looking for a humidifier will want to conduct research into which type is best for them and their home.

Humidifiers are basically units that provide air with more moisture. There are various different types, as mentioned, but the goal is the same: to increase the level of humidity in a room, home or building in order for those inside to feel more comfortable. There are several benefits to this, including helping with dust allergies, helping with sinus infections, preventing nosebleeds, keeping warm air circulating through your home and much more – humidifiers can even help your furniture, wallpaper and other items in your home last longer.

Humidifiers are particularly useful during colder months, when the nasty effects of cold weather are most pronounced and the air inside your home can be very dry. In addition, if you live in dry, warm conditions, a humidifier can help bring about the right balance of moisture in your home.

Depending on your personal preferences and exactly what you’re looking for, when purchasing a humidifier you will have to decide initially between the ultrasonic humidifier and the evaporative humidifier. So, how do you decide? Read on to find out the differences between an ultrasonic and evaporative humidifier.

Why buy a humidifier in the first place?

You should buy a humidifier to achieve a balance of moisture in a room or building. Moisture in a room is essential for staying healthy and can help alleviate many unpleasant things that we are unaware come from dry air. Chapped lips, nose bleeds, dry skin, sinus infections and much more can be helped by having a humidifier in your home. Most homes will suffer from an imbalance of moisture, especially during winter months, and so most people will immediately notice the benefits of having a humidifier in their home.

In winter, having a humidifier is a great idea. Most people find that winter is the time of year they most rely on their humidifier. When cold air is heated indoors, humidity levels can go below the recommended level.

The lack of humidity in the air can also affect your furniture by shrinking the wood or creating cracks. By increasing the relative humidity in the air, you’ll feel much more comfortable around the house.

What is an evaporative humidifier?

An evaporative humidifier is the simpler of the two kinds of humidifiers in terms of sophistication. The evaporative humidifier is also known as a “wick humidifier” owing to the way it works. It consists of just three major parts: a fan, a wick and a reservoir. An evaporative humidifier pull air into it using its internal fan. This air will then pass along a water-saturated wick filter which has absorbed water from the reservoir. The air will then absorb some of the moisture into it and will then be emitted back out into the room to give the room a healthy balance of humidity.

This process is self-regulating, since the evaporation from the wick depends on the humidity of the room.

What is an ultrasonic humidifier?

Ultrasonic humidifiers features a water reservoir that is then turned into moisture to improve the humidity levels in your home. Instead of a wick and a fan, as we find in an evaporative humidifier, ultrasonic humidifiers feature a tiny metal plate that vibrates at an ultrasonic frequency. This plate’s vibrations are extremely powerful. In fact, they are so powerful that they break apart water particles inside the reservoir. Once the particles are split they become a cool vapor which is then emitted as a fine, invisible mist into your room. The effect of this is to bring about a healthier balance of humidity in your room.

What are the major differences between an ultrasonic humidifier and an evaporative humidifier?

Ultrasonic humidifiers are currently the most popular type on the market. This is for a variety of reasons, including the fact that they are generally quieter and more efficient.

The drawback of ultrasonic humidifiers, however, is that they also produce white dust. White dust is produced as a result of mineral build up in the humidifier, which can happen over time since the water used in the unit is unlikely to be 100% pure. Without due care and regular cleaning, this white mist can eventually be emitted into the air and cause problems.

Evaporative humidifiers suffer from this less, but do come with their own advantages and disadvantages. Running costs are generally more as filters need replacing, and it is rare to find an evaporative humidifier that runs as quietly as an ultrasonic humidifier.

Should you buy an ultrasonic humidifier or an evaporative humidifier?

Choosing the right humidifier for you will depend on a whole range of different things, the most important ones being what is right for your home and what is right for you. The major considerations are price, noise level, health issues and design. Here we look at these topics in detail.


The cost of your humidifier will obviously vary depending on the model you choose. Economic options are available in ultrasonic humidifiers and also evaporative humidifiers.

Generally speaking, an ultrasonic humidifier will be more expensive than an evaporative humidifier. Towards the lower end, evaporative models can be very basic since the technology is not quite as sophisticated. Equally, when you are looking at more expensive models, ultrasonic humidifiers can offer both warm mist and cold mist options; fully automatic functioning, and a variety of different options that are a little more difficult to find on evaporative humidifiers.

On the other hand, the initial outlay could be outweighed by the cost of maintenance and upkeep for the evaporative models. With evaporative models you will frequently have to change the filter and wick, therefore costs can build up. In terms of maintenance, the upkeep of your ultrasonic humidifier will be less, even though it will require regular cleaning.


Having a humidifier in your bedroom can help you sleep soundly, avoid noise bleeds and even reduce snoring. For that reason many people put their humidifier in their room, and so noise levels are certainly a concern.

Ultrasonic humidifiers such as the PowerPure 5000 Ultrasonic Humidifier are extremely quiet, almost silent models and therefore do not threaten to disturb your night’s sleep at all. On the contrary, many evaporative humidifiers are much noisier since they require the use of a fan system. These fan systems can have a constant humming sound to them which, for people who sleep lightly or are easily disturbed by noise levels, can become irritating.

So if you think noise may be an issue for you, it would be prudent to opt for an ultrasonic humidifier. If this is not your priority and price is of tantamount importance, the evaporative humidifier could be the one.

Health issues

Ultrasonic humidifiers require maintenance to keep them clean. If you do not do this you risk the unit having a buildup of minerals which can eventually lead to white dust being emitted into your home. Without a good, clean filter and a water decalcification unit this can turn into dust that may trigger allergies or cause illness.

Evaporative humidifiers do not suffer from this so easily, and so if you do not wish to regularly clean your humidifier, you might find that this is the better option.

If you are sure to follow the instructions given to you when purchasing your humidifier, you should not have any troubles with health issues. By keeping them clean and replacing the parts as recommended by the manufacturer, the only changes in health when you have a humidifier should be positive ones: healthy skin, relief from allergies and much, much more.

Maintenance and upkeep

As mentioned, the ultrasonic humidifier requires regular maintenance to ensure the air that is in your home is not just appropriately humid, but healthy and free of white dust, too. In order to ensure this white dust does not get promoted around the house, be sure to clean your unit regularly. Also be sure to use distilled water at all times and, if you can, try to buy a filter to attach to your humidifier.

Evaporative humidifiers require less regular upkeep, but the individual parts of the model will need replacing more frequently than those in the ultrasonic humidifier. The wick will need replacing every 60 days or so, and other parts may require replacing after 500 hours of use. For each humidifier it is different, and we recommend checking the individual model for more specific timings. Be sure to abide by the recommendations given by the packaging of your unit, since to do otherwise is to risk the buildup of bacteria in your home.


Of course, personal taste is the deciding factor when it comes to design. Different people will prefer different models, and the way someone’s home is designed will obviously impact upon whether the unit looks good in the house.

It is difficult to say if one style of humidifier has a better design than the other, though it is fair to say that reviews in general are more favorable when speaking about the design of ultrasonic humidifiers. Since the units come with more functionality and a greater level of sophistication, more time and effort is invested in the design, too. Some modern ultrasonic units are particularly sleek looking, and settle in nicely into any modern home.

So which is the one for you?

Which humidifier you buy will depend upon what you most value. Generally speaking, ultrasonic humidifiers are more sophisticated and come with more options. The design is usually a little nicer and there are fewer ongoing costs. Ultrasonic humidifiers are the more popular of the two on the market at the moment.

Evaporative humidifiers, however, are still extremely popular. Their low upfront cost is appealing to many customers, and for those simply wishing to increase the humidity levels in their home with no frills and not too many worries about maintenance, this is the best option.

Either way, buying a humidifier is a great thing for you home. They can help maintain wooden furniture longer, help houseplants breathe, help your skin develop a healthy glow, stop nose bleeds, help with allergies and more.