Live Science Verdict
Although it may not be best for bedrooms, the Honeywell Top Fill Cool Moisture Humidifier is a great option for humidifying extra-large rooms or multiple rooms at once.
Filter cleans minerals from water before it’s vaporized
Two large water tanks
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In this review, we’ll describe everything you need to know about the Honeywell Top Fill Cool Moisture Humidifier, a cool-mist humidifier made for extra-large or multiple rooms. We’ll explain how the humidifier works, how easy it is to put together and to clean, and how quickly it humidifies a room.
Two large water tanks (3-gallon capacity)
Large filter to reduce minerals
Good for hard water
Wide tank opening is easy to clean
Three fan speed settings
Evaporative humidifier leaves no visible mist
Top-fill tanks are easy to fill
Meant for extra-large or multiple rooms
Adjustable humidistat maintains set humidity level
The Honeywell Top Fill Cool Moisture Humidifier is an evaporative humidifier, meaning it pulls dry air from the room into a wet filter and pushes humid air out. Because it has to have room for the filter, it is larger than ultrasonic humidifiers, which tend to be filterless. However, the filter does remove many minerals from the water, especially hard water, keeping the white dust that can settle around a humidifier to a minimum.
Compared to other humidifiers in its price range ($100+), the Honeywell Top Fill Cool Moisture Humidifier has fewer features. It’s a basic humidifier with very simple controls, but has two large water tanks and can quickly raise the humidity of large rooms.
The Honeywell Top Fill Cool Moisture Humidifier is available in either black or white to tie into the design of your room, but is quite large and bulky so you’ll want to consider where you’ll put it before choosing this humidifier.
Honeywell Top Fill Cool Moisture Humidifier review: How big is it?
- Height: 13 (in)
- Depth: 13.4 (in)
- Width: 21.3 (in)
Compared to other humidifiers we’ve tested, the Honeywell Top Fill Cool Moisture Humidifier is large and bulky. While it can and will fit onto a dresser or counter, it takes up a lot of space. The user manual advises against putting the humidifier on any surfaces that can be damaged by water and also suggests placing it at least 12 inches away from any walls.
Because the water tanks are tall, they don’t fit easily into shallow bathroom sinks. Our tester used the humidifier in her bedroom and carried both tanks to and from her kitchen to fill them. However, the top-fill feature of this humidifier also allows you to leave the tanks in the humidifier and fill them with water from a jug. As this humidifier holds three gallons of water, that may mean taking multiple trips to fill it up.
Our tester found that the bulkiness of the Honeywell Top Fill Cool Moisture Humidifier does not make it ideal for a bedroom. Although Honeywell doesn’t specify a range of room sizes for this humidifier, it’s meant to humidify extra-large spaces or multiple rooms. Therefore, it’s probably best for something like an open living room.
Honeywell Top Fill Cool Moisture Humidifier review: How easy is it to use?
There’s a little bit of assembly required to put the Honeywell Top Fill Cool Moisture Humidifier together. The humidifier comes with two float paddles that have to be installed before you can start using it. Our tester found the paddles very easy to put in — they snap into place with just a little bit of pressure. The user manual also suggests taking out the included filter and saturating it in water before you start using the humidifier.
The filter absorbs water from the two water tanks. A fan sucks dry air in from the room, passes it through the filter, and pushes hydrated air back out. Wetting the filter first use helps this process along. The filter is easy to remove and put back in — you simply lift off the top of the humidifier, pull the filter out, wet it, and put it all back together.
Unlike other humidifiers we’ve tested, the Honeywell Top Fill Cool Moisture Humidifier has very basic features. There are only two controls, one with a water droplet symbol and one with a fan symbol. The fan symbol simply controls the speed of the internal fan, with options for low, medium, or high. According to the user manual, high is for fast humidifying, medium is for everyday moisture control, and low is a “quiet setting.”
The knob with the water droplet symbols ranging from one droplet to three is for humidity control. When you first turn the humidifier on, you should turn it to the highest humidity control (three droplets) and run it for at least an hour, then you can turn the humidity control lower. Once the “Humidity Reached Indicator” light turns green and the humidifier turns off, your desired humidity level is set. The humidifier will automatically turn on when the room drops below this setting and turn off when the humidity level is reached.
Our tester found these controls to be a bit confusing, especially compared to humidifiers that have screens that let you very clearly set a target humidity level. It’s unclear what humidity you’re setting the device to when you turn the humidity control down, unless you have a separate humidity meter (which Honeywell also sells).
Honeywell Top Fill Cool Moisture Humidifier review: Performance
We tested the Honeywell Top Fill Cool Moisture Humidifier on all three fan speeds. On high, the humidity in our tester’s room increased from 51% to 56% in the first hour and increased another seven percent to 63% within the next hour. Compared to other humidifiers we’ve tested, this is a very fast increase rate. It should be noted that our tester’s bedroom is 234 square feet — a large bedroom, but smaller than the space this humidifier is meant for.
On medium, the Honeywell Top Fill Cool Moisture Humidifier increased the humidity in the room from 65 to 68% within an hour, and another two percent in the next hour. On low, the “quiet mode,” the humidity in the room rose from 48% to 50% in one hour and to 53% in the next hour.
Because this humidifier holds three gallons of water, it can last a long time without a refill. On the lowest setting, the two tanks should last 24 hours. When we tested it on high, the humidifier was still running after 14 hours.
Once she understood how the humidity control knob worked, our tester found the Honeywell Top Fill Cool Moisture Humidifier easy to use. However, it’s loud compared to other humidifiers she’s tested. On its highest setting, the humidifier registered 50 decibels on a noise meter. As the room registered 25 decibels without the humidifier on, it effectively added 25 decibels of noise to the room. This is much louder than the 5-7 decibels other humidifiers added to the room’s noise level.
Honeywell Top Fill Cool Moisture Humidifier review: What’s good about it?
We like how quickly and effectively the Honeywell Top Fill Cool Moisture Humidifier raises the humidity of a room. It’s an excellent option if your space is very dry and you don’t mind white noise in the background.
The Honeywell Top Fill Cool Moisture Humidifier is a no-fuss humidifier. It doesn’t have the extra features of similarly-priced humidifiers (at more than $100), such as app-control, screens that show the room’s humidity level, and aromatherapy diffusers. However, it’s an excellent humidifier for the simple purpose of increasing the moisture in your environment. We would suggest the Honeywell Top Fill Cool Moisture Humidifier for a large apartment or for people who want to humidify several rooms.
Honeywell Top Fill Cool Moisture Humidifier review: What’s not so good about it?
If you want features like a screen that shows the humidity and the ability to set a specific humidity target, the Honeywell Top Fill Cool Moisture Humidifier isn’t for you. At more than $100, you could get a humidifier with many more bells and whistles.
Even if a basic humidifier is what you’re looking for, the Honeywell Top Fill Cool Moisture Humidifier might not be the right option. This humidifier is very large compared to other models, which lets it hold a lot of water and provides space for a filter that clears the water of minerals, but makes it bulky. It’s also louder than similarly priced models, making this humidifier less good for bedrooms (unless you happen to enjoy white noise while you sleep). The noise is comparable to running an air conditioner — if that level of noise disturbs you while you sleep or while you watch TV, this humidifier won’t be good for either a bedroom or living room.
Even though it has a filter, the Honeywell Top Fill Cool Moisture Humidifier requires frequent cleaning. The user guide recommends cleaning it once a week to remove built-up minerals. However, this cleaning schedule is similar to other humidifiers.
Because the Honeywell Top Fill Cool Moisture Humidifier has a filter, it also requires slightly more upkeep than filterless models. You’ll have to replace the filter every 30 to 60 days, and more frequently if you have hard water.
Honeywell Top Fill Cool Moisture Humidifier review: User reviews
Amazon users rate the Honeywell Top Fill Cool Moisture Humidifier a 4.5 out of 5. Those who like the humidifier like that it quickly and effectively raises the humidity of a room.
Others like that the Honeywell Top Fill Cool Moisture Humidifier is an evaporative humidifier, as opposed to an ultrasonic humidifier. Because it’s evaporative, no visible mist comes out of the humidifier and the humidity output depends partly on how humid the room is to start.
People who were less thrilled with the Honeywell Top Fill Cool Moisture Humidifier think the filters and the water tanks are too flimsy. One reviewer writes that, especially if you have hard water, replacing the filter can get expensive.
Should you buy the Honeywell Top Fill Cool Moisture Humidifier?
The Honeywell Top Fill Cool Moisture Humidifier is a great no-frills humidifier that can quickly raise the moisture level in large spaces. We recommend it for an open living room to humidify multiple rooms in your home or for a large apartment. This humidifier does make more noise and is larger and bulkier than similarly priced models, so you should take that into consideration when thinking about purchasing the Honeywell Top Fill Cool Moisture Humidifier over others.
If this product isn’t for you
There are many other humidifiers in the $100+ price range. If you’re interested in more features, our tester likes the Levoit Classic 300S, which can be controlled through an app. This Levoit model has an auto mode to automatically adjust to a comfortable humidity level, an aromatherapy diffuser for essential oils, and a night light.
We also like the Levoit LV600HH humidifier, which is not app-controlled but has many of the same features as the Classic 300S. The Levoit LV600HH also has a larger water tank than the other Levoit, holding 1.5 gallons and able to run for at least 17 hours. If you’re unsure about choosing a cool-mist vs. warm mist humidifier, the LV600HH could be a good option, as it allows you to switch between the two.
Finally, the Elechomes HTJ-2119 is another good choice within the price range. Similar to the two Levoit models, it has a built-in humidity sensor and allows you to set a specific humidity target. If you’re concerned about little ones messing with your humidity settings, this is a great option for you. A child lock keeps your settings in place until you want to change them.
Kasandra Brabaw is a freelance science writer who covers space, health and psychology. She has a bachelor's degree in science and a bachelor's degree of arts from the University of Syracuse; she completed her master's of arts degree in journalism at Syracuse University in 2014. In addition to writing for Live Science and our sister site Space.com, Kasandra has written for Prevention, Women's Health, SELF and other health publications. She has also worked with academics to edit books written for popular audiences.