What is the Best Furnace Humidifier?

A furnace has bucketloads of benefits in the winter months but it also lowers your humidity (air moisture) and could trigger issues such as your sinuses drying out chapped lips, and more.

A smart way of tackling this problem and creating a healthier, cozier environment for you and your kids is to install a humidifier for the furnace.

This is a complete guide to humidifiers for furnaces and will educate you about how they work and what to look for when buying one.

We shall conclude by bringing you our humidifier for furnace reviews to help you identify the best humidifier for the furnace.


Let’s get the ball rolling.

What’s a humidifier for furnace?

A humidifier for the furnace is exactly a furnace-mounted humidifier.

The greatest thing about these devices is that they’re whole-house humidifiers and supply moist air to your house.

Of course, standard humidifiers tend to work for single rooms only and are not designed to be part of your home’s heating/cooling systems.

How does a humidifier for furnace work?

Now, to generate the extra moisture needed to make your place comfier, this type of humidifiers mostly hooks up to forced-air furnaces (or to warm air supplies).

And the best news is that the connection is usually super easy.

The other thing you need to understand is that while there are different types of humidifiers for furnaces, they all feature a source of water (to generate the humidity) and a water collection container.

A way of blowing the air to create evaporation and a medium to control the flow of water is also required (despite some variations in the applied technology) 

Also common these days is a humidistat (to help you manage the humidity setting).

We shall tackle the types next to help you understand the differences fully.

Types of humidifiers for furnace

Here now is a rundown of the most common humidifiers for furnaces and how each function.

Flow through humidifiers for furnace (or evaporative humidifier)

As the name tells you, these have a setup that allows warm water to flow through the entire system and evacuate.

A mechanism is implemented that diverts heated air (from the furnace) into the humidifier unit where it will collect moisture from a mounted evaporator pad.

This will eventually be emitted to the environment to boost the humidity.

Reservoir type (or drum/bypass) humidifier in furnace

In these types, a container of water is mounted- connected to a water supply together with the furnace- and it will moisten a drum (the drum rotates through it) to produce moisture.

The air passing through the duct will pick up the moisture and deliver it to your rooms.

Steam humidifier for furnace

This heats water to release steam into your furnace’s airflow.

The water vapor will subsequently filter into the air to normalize humidity.

Console style humidifiers for furnace

These are closer to regular humidifiers in terms of construction- you simply plug it in, power it on, and you’re good to go.

Turning to how they moisturize, most work similarly to evaporative humidifiers for humidifiers.

Their biggest advantage is undeniably the fact that you won’t need to hire a professional installer as it’s the case with some conventional furnace humidifiers.

A word on the above types

Obviously, each type has its own merits and drawbacks.

However, overall, most people find flow-through humidifiers for furnace friendlier than the rest primarily because of the easier maintenance.

You see, they lack a reservoir where mold can grow which also means that you’ll have no messy cleanups waiting for you.

In addition, they tend to be more affordable (they use a comparatively inexpensive technology) to buy and run (they consume less energy too).

That’s doesn’t make the other terrible choices and depending on your needs, you could sometimes find them more ideal. 

Is a humidifier for furnace really worth it?

Well, admittedly, you can raise moisture by taking simple measures such as hanging wet clothes indoors to dry, spraying water with a spray bottle, growing and keeping houseplants well watered, and more.

But most of these techniques are not as effective as a humidifier for a furnace

First, you can specify the moisture level you feel most comfortable at and have it work to lift moisture to this desired level. 

Secondly, they are super-efficient and humidify the whole house.

Plus, some are pretty advanced and they can automatically moisturize the air as soon as it detects dangerous drops in the moisture level.

In short, you will notice a dramatic difference in the amount of humidity lingering in the air with a humidifier on a furnace.

And that means you’ll no longer struggle with desert-like air throughout your apartment.

Furnace Humidifiers Buying Guide

Here are some points to steer you through the myriad options when you’re buying your first humidifier for the furnace.

Check the covered area

First, you need to be sure of how big the area you want to moisturize is.

Capacity varies a lot and it’s important that you pick one that’s effective for your square footage.

Decent humidifiers start from about $120 and the bigger your house, the more you’re likely to splurge.

Be sure of its humidity output

The gallons of water the unit outputs to the warm air in a 24 hours period is another pointer towards its abilities.

Check the specifications and compare the values with what’s indicated in competing humidifiers targeting the same coverage.

It’s best to go for the highest possible output.

Research about its maintenance

Like any other device, these devices need some maintenance.

The problem is when there’s too much maintenance to do such that you find yourself wasting hours upon hours of productive labor cleaning it or undertaking other procedures recommended by the manufacturer.

I already narrated about flow-through models having the least maintenance requirements.

Installation and related questions

Ideally, the best humidifier for furnace should be a breeze to install so read the reviews and check the opinion of other buyers concerning its installation.

On a related note, a compact unit would be preferable if your furnace is located in a small room.

Presence of advanced features

Additions such as an automated on/off operation, a humidistat, intuitive digital controls, and such can make a unit a more compelling choice.

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Best Furnace Humidifiers Reviews

We have 5 outstanding units that we recommend.

They thoroughly impressed us.

Here is a review of each.

Aprilaire 700 Automatic Humidifier

The pick of the bunch is this Aprilaire 700 Automatic Humidifier because of the 0.75 gallons per/hour (18 gallons daily) evaporation capacity, one of the highest in humidifiers at this level.

Aprilaire 700 Whole House Humidifier w/Automatic Digital Control

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It’s best for tightly constructed homes not bigger than 4,200 square foot.

This fan powered flow through unit is again up to the job for homes up to 4,200 sq. ft.

It’s a high-output model and equals the 18 gallons (per day) capacity achieved by its sibling, the Aprilaire 700.


This flow through powerhouse elevates humidity pretty fast – the company says that it sends up to 50 extra moistures than competitors- and you and your pets will have a healthier environment.

But perhaps the feature that delivers a knockout blow to rivals is the automated humidification operation.

Believe it or not, thanks to the digital humidifier control, all you have to do is set your agreeable humidity level (turn the dial) and leave it to do the rest.

And make no mistake about it- its smart and will dish out optimum humidity all through.

Plus, it’s unbelievably quiet!

A couple of features got us sold to this unit including the fan control – this tests your indoor humidity and initializes the fan when it’s imperative.

This keeps room humidity steady and pleasant.

Another feature we loved is the special water valve design- it built to restrict the water flow to save water.

Just like its companion humidifier, this humidifier is fully automatic- set your wanted humidity and forget about it.

The two sensors (it’s a dual sensors unit) keeps an eye on the room humidity and outdoor temperature will adjust appropriately and you have nothing else to do.

There’s a manual option too.

Speaking of which, the super responsive-to-the-touch controls will have even the biggest novice operating it like a pro.

The size is bang on and should look sweet on your furnace.


  • Manual or automatic options to control temperature and humidity.
  • Straightforward maintenance (annual).
  • Easy DIY install.
  • Works extremely well.
  • Reasonably quiet.
  • Space-saving shape.


  • Uses more water.
  • Installation takes longer.

AIRCARE MA1201 Whole-House Console-Style Evaporative Humidifier

This humidifier proves that console type humidifiers can do the job as well as traditional furnace humidifier models.

AIRCARE MA Whole-House Console-Style Evaporative Humidifier

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It humidifies the whole house proficiently as long as you position it near your furnace’s air intake for houses up to 3600 sq. ft.


This machine has nice digital control settings for the fan speed, humidity levels, temperature etc. and there’s no guesswork.

A smooth functioning humidistat feature means that it comes on automatically once the humidity level goes below set levels (and shut off when humidity level reaches optimum level or when it needs a refill).

And oh, we love the four swivel wheels- you can move it to another room when sweeping the floor or as necessary. 

A removable tank makes refilling and tank cleaning easy-peasy.


  • Superb digital display.
  • Easy setup.
  • Easy to operate.


  • Reduced daily output (about 12 gallons) compared to Aprilaire 700.

Honeywell HE360A1075 Whole House Humidifier

Perfect for installation in variable speed and multi-stage furnace systems, this flow-through humidifier has a big heart and works like a charm for spaces up to 4,500 sq. ft.

Honeywell Home HE360A1075 HE360A Whole House Humidifier

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The unique PerfectFLO distribution water tray maximizes its efficiency and water consumption to cut down on your heating and AC Energy bills.


The beast ramps up the humidity for more ambient surroundings within minutes without adding significant noise- the output of 18 gallons/day evidences its powers.

It continues the tradition of having a humidistat that automatically turns it on/off to sustain preset humidity levels.

A pressure switch is packed to ensure that your Honeywell furnace humidifier is working and air moving before the humidifier engages.

Furnace humidifier installation is a piece of cake as you can mount it right to the furnace without going through the bypass ductwork (order the installation kit together with the unit). 

The workmanship is flawless and we were very impressed with Honeywell’s quality control in this product.



  • Expensive equipment.

Aprilaire 400M Whole House Humidifier

The Aprilaire 400M is a manual model that covers 4,000 sq. ft. with a mega-capacity of 17 gallons/day.

The manual operation gives you more flexibility to choose the humidity levels you feel most satisfying in response to outdoor temperature changes.

Aprilaire 400M Humidifier

View on Amazon.com


We like its easy-to-use controls and the single sensor that accurately guides you when specifying your predetermined humidity percent.

It employs a water-efficient evaporative technology to heighten your home’s humidity and uses considerably less water.

It follows that you don’t need a floor drain.

What’s more, a helpful indicator will remind you when it’s time to replace the water panel.

Above all, it’s truly industrious and dispenses blissful humidity 24/7 uniformly across the width of your home.


  • Conserves water.
  • Delightful after-sales support.
  • Fast results.


  • Manual setup.

What’s the recommended humidity level for your comfort and good health?

Anything within the 30% – 50% relative humidity is considered comfortable for human beings indoors.

Humidity above 50% is regarded as extremely high and is the perfect recipe for renewed mold growth (and other issues like musty odor) during the winter months.

Likewise, you will be at risk of suffering dry skin (and problems such as static electricity and shrinking wood furniture) if the humidity drops below 30%.

Be sure to set your humidifier appropriately to enjoy optimal humidity. 

Maintenance Tips for Best Furnace Humidifiers

To keep the unit running like a well-oiled machine

  • Clean any mineral deposits/scales.
  • Ensure proper water levels.
  • Check it for (and seal) leaks.
  • Replace evaporator pads and filters as indicated in the owner’s manual.

Wrapping it up

When the air heats up (after turning your home furnace humidifier on during winter), the relative humidity in your home drops.

And if unchecked, you’ll be staring at terrifying results such as your skin drying out, going down with myriad respiratory infections, itchy skin/hair, aggravated asthma symptoms, among other issues.

One of the best ways to overcome dangerously low moisture levels is by investing in a humidifier for furnaces.

You now have all the information at your fingertips including how to select one that won’t disappoint.

It’s now your turn to step up and take control of your home’s moisture.