Pure Guardian H4600 Ultrasonic (Digital Controls)

Pure Guardian H4600 Ultrasonic

Knowing the difference between warm and cool mist humidifier units is very important to understanding which unit will work best for you and your room. One thing I should make clear from the get-go is that a cool mist machine does not disperse a cold mist. What it does is emit room temperature moisture into your room. A warm mist however, will heat the water in it’s tank and disburse heated moisture instead.

In this article we are strictly going to discuss the differences between cool and warm mist machines. If you would like more information on the other styles of humidifiers available, see this article.

Warm vs. Cool. In the End, does it Matter? 

Now that we know the differences between these two, it’s a little easier to understand why one style might be used more than the other. For example, a warm mist machine is better suited for use during the winter months than during the summer. Mainly because of its heating elements. Whereas a cool mist machine is best suited for the spring and summer months, but could also be used all year round. (some units may encourage temperature drops)

With that said, if you’re looking to treat a cold. It doesn’t really matter which style you use. As per mayoclinic.com, by the time the water vapor reaches your nasal passages and your inner airways, the temperature from both will be the same. Now this may be different when treating allergies, asthma or even skin problems, but for colds and flu’s it’s not a factor.

Pros and Cons of Cool Moisture Units



– since there is no heat they are considered the safer alternative to use in your toddler, newborn or children’s room.

– since there are no heating elements, this style uses less electricity overall.

– have the option of being used all year round.


– normal non-ultrasonic machines need to be cleaned very often to avoid any growth of bacteria and mold.

– temperature drops can occur when used during the winter months.

– depending on your machine you may be required to purchase filters on a regular basis.




– overall not as loud as most cool mist machines. (not including ultrasonic)

– since it creates heat, it’s the preferred option to use during the winter months.

– overall not too difficult to clean.


– because of its heating capabilities, it requires more electricity to function.

– again, because of its heating element. it’s considered more of a risk to operate around children.

Overall Thoughts:

In the end, a humidifier’s job is to help maintain comfortable humidity/moisture levels within your home. I think whether you prefer a cool or warm mist is more determined by personal preference than anything else in my opinion. I hope this article has helped you come to a better understanding and you’re now able to make a decision on which one to go with in your home.

Click here for a review of the The Pure Guardian H4500 Ultrasonic Warm & Cool Mist Humidifier