The 5 Best Whole House Humidifiers For Furnaces of 2025

Nothing is worse than having a home in a cold climate with super dry air.

Dry air can cause nose bleeds, itchy skin, static electricity, and even shrink your hardwood floors. The main recommendation by the EPA is that we should strive to keep our homes indoor humidity between 30% and 50% to minimize health problems and for a comfortable environment.

There are two main types of whole house humidifiers that can fix the problems of dry air:

1. Built-In & Ducted. These centralized HVAC humidifiers are installed onto the ductwork of your HVAC system, usually right next to your furnace or heat pump.
2. Console. The console type of whole home humidifier is a portable free-standing humidifier that can humidify an entire home (much larger than desktop units) — and you can just plug it in a regular 120-volt outlet. 

Below is our shortlist of the top picks for the best HVAC humidifiers. Keep reading to learn how to choose the top one, key buying criteria, and our detailed reviews!

How Do Large Home Humidifiers Work?

Whole house (HVAC) humidifiers and portable humidifiers can both humidify your home, but there are some key differences you should know about.

I don't think there is any disputing within the home industry that nothing compares with central humidification systems that are installed on your HVAC ductwork. These machines can operate automatically, and send the right moisture to each and every room of the house (even if the doors are closed).

Nevertheless, these ducted humidifiers can be costly and difficult to install while a console humidifier can moisturize an entire home or large room and do a pretty good job (without the headaches). Here is how each humidifier type works:

1. Portable Whole House Humidifiers

Portable or 'console' style whole house humidifiers are a great option for some homeowners who don't want to break the bank. These large whole house humidifiers are appliances that you can put in a living room or hallway. And yes, they are portable humidifiers, but they are much bigger and heavier than the common desktop style humidifiers that most people have.

How much moisture can a console put out?

Portable humidifiers can put out a whopping 3-7 gallons of moisture into your home each day. This is usually far less than a built-in whole house humidifiers, but it may be sufficient for a single level or for a moderately sized home, and it is considerably more than desktop humidifiers. If you have a large home, these console whole home humidifiers generally won't work well.

For these console humidifiers, you will have to refill the water tank pretty frequently. How often may be 1-2 times a day, or it up to a few days at most. The refill frequency depends on the size of the console humidifier, the dryness of the air, and the fan speed. Console humidifiers also have a wick that you will to change every 1-3 months.

2. Whole House Furnace Humidifiers

Whole house humidifiers for furnaces are literally screwed into the HVAC ductwork, usually right above or next to the indoor furnace, heat pump, or air handler. These HVAC whole house humidifiers usually have a daily moisture capacity of around 10 to 30 gallons per day. These units are the top choice if you want to deliver humidity throughout the whole house.

There are three main types of central humidifiers:

Steam Type

Probably the highest quality type of home humidifier system is the steam type. Rather than sending liquid water down an 'evaporator pad', steam humidifiers super heats the water using a heating element or electrodes and turns the water into steam. For more details, you can read my complete guide on the highest rated steam HVAC humidifiers right here.

With steam humidifiers, it is usually far easier to reach your desired indoor humidity level because the moisture output is much higher than conventional humidifiers. Steam whole home humidifiers are much more energy efficient and are less wasteful of water.

Bypass Type

The bypass type of central humidifier uses a 'bypass duct' which connects the whole house humidifier to the HVAC main duct, and it is likely the most common type of whole house humidifier. Bypass humidifier models do not have their own fan, so they can only work when the furnace or HVAC is actually turned on.

The bypass duct siphons off some of the HVAC air flow, and this air goes through the humidifier which sends moistened air back into the main HVAC duct—and throughout the entire home. A small stream of water trickles down an “evaporator panel” or pad which is what gives moisture to the air when air blows over it.

The upsides to the bypass whole home humidifier system is that they are simpler humidifiers (no power or fan) and far less expensive than steam units. 

The negatives of these humidifiers is the necessity of a  bypass duct that needs to be installed (if there is room). These whole home humidifiers do not have high moisture output which may make it more difficult for you to reach your desired humidity. Basically, bypass humidifiers are less efficient than the fan-powered type or steam type.

I invite you to read my full guide on steam vs. evaporative built-in humidifiers here for more information.

Powered Type

The powered type HVAC humidifier has it's own power supply and it's own fan. This home humidifier doesn't need the HVAC to be on for it to be running. It is more efficient than the bypass because less moisture is lost since it doesn't have to pass through the coil and heat exchanger (like the bypass type). A powered fan type of humidifier can send about 1 gallon more moisture into the air in a day than the bypass type. The downsides are that the fan-powered type is more expensive and will be costlier to repair.

You may want to check out my complete guide on how humidifiers for houses work here.

How To Pick A Humidifier For Whole House?

Purchasing the right whole house humidifier that is sized correctly for your home is crucial, but it isn't the only buying consideration. The cost of whole home humidifier systems varies widely, from less than $200 to upwards of $1500 (cost & labor). Here are a few of the most important buying factors:

1. Size of Home

The size of your home is going to be a crucial factor in your central humidifier decision. Both console and HVAC humidifiers will give you the manufacturer recommendation for the maximum home size.

Most portable whole house humidifiers will be rated for homes in the 2,000 to 3,000 square foot range. Built-in whole home humidifiers are usually in the 2,500 to 6,000 square foot arena.

Also, instead of pushing the limit for a console whole home humidifier, it may be a better choice to get a smaller unit but multiple humidifiers such as one for each home level.

2. Budget

The budget is another key buying consideration with central home humidifiers. There is a significant price difference between HVAC humidifiers and console humidifiers.

Adding up the cost of installation is a big factor

When you factor in the cost of the HVAC humidifier such as all of the installation materials, and the professional labor cost — it can be several times more expensive than the console. As an example, the AprilAire 800 steam humidifier, when you consider the cost and labor, may total more than $1,500.

With console humidifiers, you can get a decent model for a home up to 2,500-sf at less than $250.

3. Water Capacity (Gallons)

Another important consideration after choosing the type of humidifier is the water capacity. Portable whole house humidifiers have the lowest capacity, and usually put out only 3-7 gallons of water per day.  As you can imagine, delivering the desired humidity throughout a large home with a console humidifier can be a difficult task.

In contrast, furnace humidifiers can deliver anywhere from 12 to 30 gallons of water per day. Of course, the down side is that HVAC whole house humidifiers are more difficult to install, and the overall cost can be much more mainly due to the labor.

4. Thermal Envelope of Home

The thermal envelope is basically how well your home is insulated and air-sealed. If you have old single-paned windows, poor attic insulation, leaky air ducts, and lack of external wall insulation — it is going to be harder to humidify your home (as well as heat it).

How well insulated and air-sealed is your home?

If you have an older and leakier home, you may need to get a whole home humidifier that has a higher capacity, or you may need more than one humidifier.

5. Runtime

Runtime is the amount of time a console humidifier will run prior to having to fill it again with water. HVAC humidifiers don't have this issue because it is directly connected to the home's water supply.

With some portable whole home humidifiers, you will need to fill it up 2-3 times a day if you use it continuously or on a high speed setting. With other humidifiers, you may only need to fill it up every few days.

6. Ease of Filling

Some console humidifiers are also easier to fill up with water than others. There are humidifiers with removable water tanks where you can remove it and take it to the sink to fill it up. But even if it doesn't have the removable 'bottle style', you can always buy a pitcher to make it easier to fill it up.

The weight of the unit can also be a factor if you just want to lift it up to a sink and fill it up. Some humidifiers can be more than 20-lbs which can make it more challenging to lift it and fill it for some users. Also, some humidifiers have tiny water spouts which can make it frustrating to fill it.

What Are The Risks of Home Humidifier Systems?

Even though whole home humidifiers provide a lot of health benefits, they can also turn against you if it isn't properly maintained. Probably the biggest hazard of humidifiers is the mold risk, and the second is the possibility of water damage. Here are a few safety considerations when you buy a whole house humidifier:

1. Mold Inside Portable Whole House Humidifiers

The biggest hazard with console humidifiers is mold growth. You may be running a console humidifier for quite a while without realizing there is mold growth inside the machine. The easiest way to prevent mold growth in a console humidifier is to regularly treat the water tank with a tablet/liquid bacteriostatic treatment.

A bacteriostatic liquid is an anti-microbial agent that will kill and prevent mold growth in the water tank and on the wick.  Since it inhibits mold and mildew growth, it should also make the unit run better and extend the life of the wick. If you want to learn more about preventing mold, you can read my complete guide on whole house humidifiers and mold right here.

Regular Cleaning And Wick Changes

Besides a bacteriostatic solution, you should also clean the humidifier regularly as specified by the manufacturer. For most humidifiers, you can clean it with a white vinegar solution. You don't want to use bleach because it can damage the humidifier and may release it into the air. You will also need to change the wick at least every heating season, but possibly as often as every 1-2 months.

2. Excess Moisture & Mold With Whole House Furnace Humidifiers

One of the biggest risks with ducted humidifiers also has to do with mold, but it is usually external to the humidifier (not inside it). With central HVAC humidifiers, it is pretty easy to over-humidify your home, especially if you have a high capacity humidifier. And if you don't control the humidity level properly based on the outdoor temperature, you may release far too much moisture into the home.

If you notice condensation on your windows, that is probably the biggest indicator that there is too much moisture. This excess moisture can lead to mold growth around the home such as on the walls, on the roof sheathing and joists in the attic, and around the window trim, baseboards, and door trim. You should always be monitoring the indoor relative humidity with a simple $10 humidistat.

3. Water Damage

Whenever you have a home appliance that uses water, there is a risk of flooding or water damage. With console humidifiers, you are risking a limited amount of water such as a 3-6 gallons (the size of the water tank). But with central humidifiers, it can cause significant water damage if there is a leak since it is connected to the plumbing.

This is even more true if the whole house humidifier is installed in an attic where the leak can trickle down to the lower levels. So if you plan on installing an HVAC humidifier in an attic, finished basement, or on a main level — I highly recommend installing a water alarm. Water alarms will make an audible sound if it detects water on the ground (or in the HVAC pan) and some can even be WiFi connected so you get an alert on your phone.

What Are The Benefits of Whole Home Humidifiers?

There are some significant health and environmental benefits to having an adequately humidified home during the cold season. If you have ever woken up with a scratchy throat, itchy eyes, itchy skin — you know how bad dry air can be. Here are a few of the benefits of buying a house humidifier:

Reduces Flu & Viruses

There are numerous scientific studies that show how dry air facilitates the transmission of viruses and other pathogens. For example, the amount of moisture in the air affects the airborne survival and transmission of the influenza virus.

The basic idea is when someone is sick they release tiny droplets that can travel much farther in dry air. In properly humidified air, these tiny droplets are more likely to just fall to the ground than to get dispersed around a large area. Also, in dry air, it is more difficult to clear airborne viruses from your nasal passages.

Dry Skin

Dry skin is the plague of homes in cold climates. Dry air can even result in winter itch or winter xerosis which can produce an itchy sensation all over the body.  It can get so bad that the occupant may think they have poison ivy or some other malady. Having the proper humidification during winter (30-50%) can relieve dry skin problems and make your entire body feel more comfortable.

Save On Energy Bill

When your air is drier, it actually feels cooler. So when you add humidity to your home, the air holds more heat, and you feel warmer. This means that you can turn down the HVAC temperature and still feel comfortable.

It is estimated that for every one degree that you turn down the HVAC temp, you can save 3% on your energy bill.

Static Shocks

Static electricity shocks can be a frustrating problem in a home with dry air.  Drier air is more likely to result in a buildup of static electricity, and since air moisture is a natural conductor --- static shocks are the result. Adding humidity to the indoor air will help prevent static electricity shocks.

Protect Wood & Furnishings

Dry air can shrink, warp, and crack your home's interior wood. Whether it is your wood flooring, furniture, cabinets — it can damage these precious objects.

Dry air can also cause damage to costly musical instruments. And even your books, paintings, and pictures aren't immune from the hazards of dry air.

How To Install And Maintain Large Home Humidifiers?

Installing a portable type of whole house humidifier really isn't difficult at all. You simply fill the water tank, turn on the unit, and set the desired indoor humidity. There are usually different fan speeds you can select as well. Here are a few installation and maintenance considerations:

Where to place it?

A good place to put a console whole home humidifier is in a central location. If you have a three level home, you would want to put it on the second level, and preferably towards the middle. You also want to keep it at least 6-inches from the walls to avoid any kind of moisture damage and to maximize air flow.

You may want to also consider placing the humidifier near a return vent for your HVAC system. The return vent is the one or two large rectangular vents which serves as the 'intake vents' for your HVAC system. So when your furnace or heat pump turns on, it will suck in the humidified air into the return vent and send it out throughout the entire home.

Refilling The Water Tank

One of the biggest downsides with console humidifiers is the continuous need to fill up the water tank. When the tank goes dry, your home goes dry. And with some consoles, it can be a pain to fill it up with water.

You may want to consider buying a large plastic pitcher to make it easier to fill it up. Also, some consoles have 'water bottles' that you can separate from the unit so you can fill it up at the sink.

Bacteriostatic Solution

A bacteriostatic treatment is an anti-microbial liquid or tablet that you can insert into the water tank to prevent mold and mildew growth. Mold sometimes grows in the humidifier or water tank that you may not be able to easily see. Needless to say, a humidifier that spews out mold spores into your indoor air is the last thing somebody wants.

Cleaning & Wick Replacement

Console humidifiers also require regular cleaning. And if you don't use distilled water (probably won't since these units are big), mineral deposits will build up on the unit and the wick. The mineral buildup means you will need to change the wick at least every 1-3 months. Cleaning the console humidifier with a vinegar solution will also be needed (don't use bleach).

Refilling The Water Tank

One of the biggest downsides with console humidifiers is the continuous need to fill up the water tank. When the tank goes dry, your home goes dry. And with some consoles, it can be a pain to fill it up with water.

You may want to consider buying a large plastic pitcher to make it easier to fill it up. Also, some consoles have 'water bottles' that you can separate from the unit so you can fill it up at the sink.

Buy A Humidistat

You can purchase a cheap $10 humidistat to monitor your indoor humidity levels. In addition to the humidity sensor on the console, monitoring the humidity with a separate humidistat is highly recommended. The EPA recommends to shoot for a minimum of 30% indoor humidity and a maximum of 50%.

Too much humidity can be just as bad as too little humidity, and overly high moisture will fog the windows and lead to mold growth.

How To Install And Maintain Humidifiers For Furnaces?

For furnace humidifier, the installation is much more of a challenge. In general, installing a whole home humidifier isn’t for a homeowner with little or no DIY skills. On average it will take at least a few hours to  install a whole home humidifier onto ductwork and possibly longer. Below are a few installation considerations:

Wiring & 220V

With some units, you will have to install the humidifier into the furnace wiring and tie it into your thermostat. With other humidifiers, very little wiring is required. HVAC home humidifiers are installed at the furnace (or heat pump) on the supply or return side.

For higher powered central humidifiers, you will probably need to hook it up to a 220-volt circuit if you want it to run at full capacity. This means you may need to route a new 220-volt line to the HVAC utility room or attic — and install a disconnect. If there isn't an existing outlet by your heat pump or furnace, you may need to wire a new outlet to plug in the humidifier.

Ductwork

For bypass or fan-powered humidifiers, you will need to will have to cut into the ductwork, and the humidifier will be inserted into the circular cut and fastened with some screws.

Drainage

All central HVAC humidifiers need drainage. You will need to know where you are going to drain the humidifier if you purchase a bypass, powered, or steam humidifier. Does your utility room already have a floor drain? You can then send the humidifier water to the floor drain.

If you don’t have a floor drain, you may be able to send it to an existing sump pump or to a condensate pump. The condensate pump (which may be right next to the furnace already) or the sump pump will send the water to the outside or possibly to a utility sink.

How To Control In-Home Humidifier Systems?

Controlling a whole house humidifier is usually a 'set it and forget it' affair, but there are a few things to consider such as the outdoor temperature and even connecting it to a smart thermostat.

Auto Mode

Pretty much all whole home humidifiers have an auto mode where you can set the desired humidity level. The humidifier will turn on and off as the humidity reaches that level and drops below it. The possible downside is the 'swing' may be too low, and even if it just drops one percent in humidity it may cause the humidifier to 'short cycle' — turning on and off too often.

Fan Speeds

With console humidifiers, there are usually between 1-5 fan speeds which are independent or work together with auto mode. If you have issues with the noise level of the console unit, you can set it to a lower fan speed. But if you want a faster degree of humidification, you can set it to a high fan speed.

Humidistat

All humidifiers have a humidistat which is basically a sensor for indoor relative humidity. You can control the humidistat setting to let's say 45% indoor humidity, so the whole house humidifier will keep pumping moisture into the air until that 45% level is hit—then it will automatically turn off.

Outdoor Temperature Sensor

Some central humidifiers such as the Aprilaire 800 humidifier also have an outdoor temperature sensor (in addition to an interior humidistat) which helps it regulate indoor humidity to an even greater degree.

The indoor humidity isn't stable since it is based on the outdoor temperature. If the temperature suddenly drops outside, but you keep the indoor target humidity at the same level — then this may cause a large increase of indoor moisture. This is because when the outdoor temperature drops, the air naturally becomes drier. When the outdoor temperature drops, you need to reduce the indoor humidity target.

If there isn't an outdoor temp sensor, you will have to try to anticipate the outdoor temperature and manually adjust the humidity level.

Smart Thermostat

You may be able to control your HVAC humidifier with a smart thermostat. And there is a possibility that you can even program it to adjust the humidity levels based on the outdoor temperature.

But even if the smart thermostat can't adjust it in conjunction with the outdoor temperature, a smart thermostat will allow you to set alerts and control the humidifier through the thermostat or even a phone app.