Winter tends to bring low humidity. This is due to the cold temperatures, which create dry air. When there is dry air, there is no moisture, and this leads to things like colds and the flu, along with allergies.
Introduction to Furnace Humidifiers
When buying a humidifier, you have plenty of different options to choose from. This article is concerned with a humidifier that can work directly with your furnace. One that connects to both your heating unit and water line.
In this short buying guide, we’re going to be taking you through the key factors that must be considered, along with why you should make this investment.
Our Recommended Humidifiers for the Furnace in 2023
Honeywell HE360A Whole House Humidifier (HE360A1075)
This whole-house unit by Honeywell is ideal for those who want a basic yet effective way to humidify their entire home.
Powered by a single-speed fan, this Honeywell humidifier distributes up to 3.5 gallons of water per hour. You can use the humidifier with any multi-stage forced-air furnace, and a valve lets you adjust the flow rate.
You won’t have to contend with a massive beast during installation. The Honeywell HE360A is a small humidifier, measuring 15.25 by 14 by 10.25 inches. Despite its size, the whole-house humidifier can circulate moist air throughout 4,200 square feet, making it suitable for spacious homes. Thanks to the PerfectFlo distribution tray, water loss is minimized.
Installation is relatively easy. The HE360A mounts directly to your furnace’s warm-air supply without the need for a bypass duct.
Honeywell provides you with installation equipment such as drain connections, tubing, a saddle valve and a wiring kit. The included humidistat offers simple controls, kicking on the humidifier when the blower motor starts running.
An aluminum mesh filter pad soaks in water with its absorbent coating. The filter pad lasts anywhere from 1 to 3 months, which should average out to twice yearly changes.
No tools are required to change the filter – All you need is 5 minutes to spare. If you run into a problem, Honeywell provides a 1-year limited warranty on the HE360A humidifier.
- Powered flow-through humidifier
- Easy installation and best choice for variable speed and multi-stage systems in homes up...
4) Aprilaire 700 Automatic Humidifier Review
The super-quiet Aprilaire 700 Automatic Humidifier is a great choice for people who don’t have time for frequent maintenance.
The evaporative flow-through humidifier is equipped with an integrated fan, which directs the furnace’s hot air into the humidifier for whole-house humidification. Due to its efficiency, the Aprilaire 700 achieves a flow rate of 0.75 gallons per hour.
In tightly sealed homes, the humidifier can moisten 4,200 square feet of air; however, the average home can expect 2,100 square feet of humidification.
The 16 by 16 by 10-inch unit flushes hard-water minerals via an attached drain to prevent water accumulation and the mold growth that comes along with it. You’ll also love that the filter only needs to be changed once a year.
With the 700 model, you get installation necessities like a 24 VAC transformer, a saddle and a solenoid valve and a water panel. The humidifier also comes with a template to help you install the 700 Automatic Humidifier to your furnace’s supply plenum and a 5-year warranty to cover any defect-related malfunctions.
The digital humidistat that has a user-friendly RH dial and an easy-to-read display screen. You can run the humidifier 24/7 or only when the furnace is blowing air; the humidistat even adjusts the output according to the current indoor relative humidity and outdoor temperature.
Plus, there are indicators for the humidifier’s operating status, the filter and more.
- BUY WITH CONFIDENCE This humidifier was designed and manufactured in the U.S.A. by...
- FULL COVERAGE up to 5,300 square feet in tightly built homes with a capacity of 18 gallons...
3) Aprilaire 500 Whole House Humidifier Review
Aprilaire’s 500 Whole-House Humidifier is a drum-style unit that promises low water usage and 0-percent water loss. The belt-driven humidifier is designed to fit on your furnace’s supply plenum or cold-air return for flexible installation.
In a home of 3,000 square feet, the Aprilaire 500 produces 12 gallons of moisture output per day.
In order to humidify the air, the 500 delivers water to the distribution tray at a rate of 3 gallons per hour. A belt rotates the absorbent filter pad, pulling water in the direct path of the furnace’s warm air.
In turn, the furnace blows moist air through the ducts in your home. When necessary, the humidifier self-flushes minerals in the water via a built-in drain.
One sensor reads the outdoor temperature while another gauges the indoor relative humidity (RH).
Both sensors send this information to the humidistat, which adjusts its output accordingly. From the humidistat, you can see when the filter needs to be changed and if the humidifier is running. The activation switch lets you toggle between automatic and continual humidification.
To streamline the installation process, Aprilaire added an integrated bypass damper and a discharge change-over to the 5-year-warrantied humidifier. Valves, a template and the water panel are also supplied. After you install the humidifier, all you need to do is close the damper, change the filter and clean the water pan at the start of the off-season.
- BUY WITH CONFIDENCE This humidifier was designed and manufactured in the U.S.A. by...
- FULL COVERAGE up to 3,600 square feet in tightly built homes with a capacity of 12 gallons...
2) Aprilaire 700M Whole House Fan Powered Humidifier Review
If you have a large home, the Aprilaire 700M can handle its humidification needs. For this flow-through humidifier, Aprilaire used the time-tested evaporative method. Thanks to a strong fan, the 700M delivers 18 gallons of moisturized air per day, which is enough to cover 4,200 square feet.
The 16 by 18 by 11-inch whole-house humidifier boasts a water feed rate of 6 gallons per hour.
As the fan draws in hot air straight from the furnace, the air blows over the humidifier’s porous, ceramic-coated water panel. Due to the panel’s aluminum mesh core, you’ll only have to replace it once every year.
With the installation kit, you get a transformer and self-piercing saddle valve; most people can manage installation on their own. Once you connect the humidifier to your home’s water line, that’s it – You’ll never have to fill the humidifier yourself.
In addition to the installation kit, you also get a lot of peace of mind with Aprilaire’s generous 5-year warranty.
The 700M’s single-sensor humidistat has a dial that ranges from 15 to 45 RH. You have the choice of putting the humidistat on the wall or the furnace’s return plenum.
To determine the current indoor RH, turn the dial in both directions while listening for two clicking sounds. The RH reading in between the clicks will give you an approximate idea of the air’s moisture level.
- BUY WITH CONFIDENCE This humidifier was designed and manufactured in the U.S.A. by...
- FULL COVERAGE up to 5,300 square feet in tightly built homes with a capacity of 18 gallons...
1) Aprilaire 800 Whole House Steam Humidifier Review
Whether your house is 6,200 square feet or half that size, this steam humidifier will send plenty of moisturized air to every room. It boasts an output range of 11.5 to 34.6 gallons per day. Those who wire the Aprilaire 800 to 240-volt or 16-amp circuits will get the highest moisture delivery rate; however, the 800 still works efficiently on 120-volt and 11.5-amp circuits.
Inside the humidification unit, there’s an electrode canister with a leak-proof O-ring. A fill valve streams water to the canister, and the canister’s electrodes utilize the water’s mineral, heating the water to a boiling temperature.
Therefore, the Aprilaire 800 works best with water on the hard end of the scale.
While the 25-pound 800 is a little on the heavy side for a humidifier, it’s super-easy to install on your furnace’s cold-air return.
Once installed, the humidifier will run as long as the indoor temperature stays between 40 and 99-degrees Fahrenheit. Should a malfunction occur, Aprilaire has you covered for five years.
The two-sensor humidistat measures the relative humidity inside your home and the temperature outside of it. A digital display shows the current RH, and a sliding switch lets you choose between auto mode and continuous mode much like you would with a thermostat.
There is also an indicator light that tells you when to change the electrode canister, which happens about once a year.
- BUY WITH CONFIDENCE This high output steam humidifier was designed with electrode...
- FULL COVERAGE up to 10,300 square feet in tightly built homes. Choose from 6 levels of...
Furnace Humidifier Buying Guide
What to Look for in a Furnace Humidifier
Regular humidifiers are great. No one is denying that. They work very well, and for their purposes, they are more than ideal. But, there is one small “problem”, you might say.
The problem is that most air humidifiers can only work within a single room. Not the entire house. So, if you want to add the necessary humidity to your home, you’re going to have to either buy multiple humidifiers or invest in a humidifier that can humidify your entire home.
When you add that necessary humidity to your home, several things happen.
First, the air becomes far more moist, which lessens allergies and symptoms of things like colds and coughs.
Second, if you are already dealing with some kind of sickness – especially if it’s directly related to the dry air – it becomes far less potent, making it easier for your immune system to get rid of it.
For example, if you have a runny nose, your nasal passages will become far more moist with a humidifier, which gets rid of your runny nose.
Third, things like houseplants, and even the wood that makes up your floors, become a lot healthier and sturdier. With the dry air, house plants often suffer from a lack of moisture. The same is true of wood.
Now, if the wood in, say, your floors doesn’t have enough moisture, it can begin to degrade. Things like shrinking are quite common. If this is left unchecked, it can easily cause some very nasty damage.
The Type Of Furnace Humidifier You Are Purchasing
There are three types of furnace humidifier that you can find.
A steam humidifier is by far the most popular type of furnace humidifier. Now, steam humidifiers are unique in the fact that they produce both cool mist, as well as warm mist.
Because of this, they are the furnace humidifier that produces the most moisture, overall.
Flow-through humidifiers take the warm air that your furnace produces, and they allow warm water to trickle over it. This leads to evaporation. One of the notable things about flow-through humidifiers is that they are very, very low-maintenance, and there is no risk of mold.
Finally, we have drum humidifiers. Drum humidifiers use a large pan that is full of water, as well as a belt that rotates and passes through this pan. All of the water on the belt then evaporates.
Now, this particular furnace humidifier does require you to clean the pan on a regular basis. If you fail to do so, it can easily lead to mold.
Each one works well with any kind of furnace, but you need to consider what your needs are.
For example, steam humidifiers are great, but they do use a lot of electricity, and as such, they can be more expensive.
On the other hand, flow through humidifiers are a bit cheaper, but they only produce warm mist. If you want the option for cool mist, then a flow-through humidifier isn’t ideal.
With a drum humidifier, you have a humidifier that works very well but does require a fair amount of regular maintenance. And, of course, there is the risk of mold.
Maximum Area Coverage
Whether it’s an air purifier or humidifier, this is a BIG factor that must be considered.
Most furnace humidifiers have a Maximum Area Coverage of at least 1500 feet. Some have less, but most have around that, or more.
But, depending on how large your home is, this might not be enough. And if you don’t know the size of your home, it’s always wise to choose a furnace humidifier that has a large Maximum Area Coverage.
However, no matter the size of your home, there will be a furnace humidifier that is right for you. You have access to humidifiers with a Maximum Area Coverage of 3000 feet, and even up to 8000 feet, if not more.
Naturally, though, if your home is especially large, then you will have to pay some extra money for a furnace humidifier that can accommodate that particular space and its abnormal size.
Daily Output & Control
Most furnace humidifiers measure their daily humidity output in gallons. Some produce 19 gallons per day. Others produce 12 gallons per day. Every furnace humidifier is different.
What you want to consider is both the output and the kind of home that you live in, as well as the space that the furnace humidifier is designed for.
If you are living in a home that is two-thousand square-feet, and the furnace humidifier you are using is designed for three-thousand square-feet and produces 20 gallons of humidity per day, then that humidity will be spread around your home in fairly large quantities.
You might get too much of it. Or, depending on the furnace humidifier and the space, too little.
More often than not, it’s good to go for the furnace humidifier that can accommodate a bigger space with a bigger output.
Usually, you have many options when it comes to how much humidity is being produced. This is especially important if you know the necessary humidity levels.
Make sure that you have access to the daily humidity output. This means that you know exactly how much humidity is being produced, and what humidity levels work best for you.

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Last Update: 2023-03-23 | Affiliate links/Images from Amazon Product Advertising API