Are you looking for a dehumidifier to take care of the moisture in your crawl space?
You’re in the right place!
In this proHVACinfo guide, you’ll learn:
- What are crawl space dehumidifiers? (and why you might need one)
- What are the different types of crawl space dehumidifier? (learn which are most effective)
- How do crawl space dehumidifiers work?
- What do you look for in the best crawl space dehumidifiers? (keep an eye out for these things!)
- Our reviews of the best crawl space dehumidifiers
- And much more!

Our Overall #1 Rated Pick
January 2, 2022

Aprilaire E70 Pro Dehumidifier
Check on AmazonBecause of the enormous variety of crawl space dehumidifiers on the market, choosing the right one can be tough.--break--From a super competitive field, we narrowed it down to just five, and from those five, chose the Aprilaire 1820 Pro Dehumidifier as our top pick.--break--Why?--break--It isn’t the prettiest unit, but this industrial style dehumidifier just gets the job done. It’s suitable for up to 2800 square feet, making it more than powerful enough for the majority of household applications.--break--This is a nice, compact unit, and with a 9 gallon per day removal rate, really helps to prevent mold, termites, structural wood rot and odors in sealed crawl spaces.
In a rush? Below is a quick roundup of our top crawl space dehumidifiers!
Image | Product | |||
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Our Top Pick ![]() | Our Top Pick | Aprilaire E70 Pro Dehumidifier
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| View on Amazon |
High-End Pick ![]() | High-End Pick | Dri-Eaz Revolution LGR Dehumidifier
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| View on Amazon |
Best Budget Pick ![]() | Best Budget Pick | AC Infinity AIRTIAN T8 Crawlspace Ventilator Fan
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| View on Amazon |
![]() | AlorAir LGR Compact Dehumidifier
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| View on Amazon | |
![]() | Waykar Dehumidifier
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| View on Amazon |
What Are Crawl Space Dehumidifiers?
If your home has a crawl space, chances are you’re aware of their pitfalls.
While cost-effective for housing builders and well-intentioned for the homeowner, sometimes crawl spaces result in a hassle for those living in the home.
However, by their very nature, crawl spaces are prone to moisture-related issues including mold and wood rot.
Crawl space dehumidifiers are electrical appliances designed to absorb water from the atmosphere in a crawl space in order to prevent the above problems by reducing the overall humidity in the crawl space and maintaining the humidity at a desired level.
By reducing the humidity, they prevent the development of stale and musty odors, and can stop mold and mildew from growing.
Generally speaking, your crawl space should be at a humidity level less than 70%, ideally around 55%.

What size crawl space dehumidifier do I need?
This is one of the most common questions about crawl space dehumidifiers.
Like dehumidifiers for other parts of the home, the capacity for crawl space dehumidifiers is sized in pints per day.
The needed pints per day are determined by the square footage of the area needed to dehumidify, and the condition of the room without dehumidification.
Check out this table below to get an idea of how many pints per day you need!

What are the Different Types Of Crawl Space Dehumidifier?
There are two main types of crawl space dehumidifier.
Some are more common than others, but all are designed to do the same job.
Heat Pump Style
This is the most common style, mainly because they are typically capable of removing the most water from the air.
They actually work using much of the same technology as an air conditioning unit.
They feature a heat pump and heat exchange coils, and use a fan to blow humid air from the room over the coils.
As the coils are extremely cold, when warm, humid air passes over them, the airborne moisture immediately condenses on them.
This moisture is now in the form of water and can drip into the collection tank, or, out through a hose to a drain.
Ventilator Style
These are a lower tech option, but are reliable and cost-effective ways to reduce crawl space humidity.
Rather than removing moisture from the air, these dehumidifiers work to expel the damp air to the outside.
These dehumidifiers are usually mounted directly in an outside wall.
How Do Crawl Space Dehumidifiers Work?
In this section we will focus primarily on how heat pump style dehumidifiers work.
Heat pump style dehumidifiers work on the refrigeration cycle.
First, the humid air from the crawl space is drawn into the dehumidifier through the louvers on the side of the unit by an internal fan.
The moist air then passes over the supercooled evaporator coils.
The rapid cooling causes the moisture in the air to condense and return to its liquid form.
There won’t be streams of water here, but a noticeable amount will begin to bead up on the coils.
This water will start dripping off the coils and into either the collection tank, or out of the unit through a hose led to a drain.
Now that the moisture is removed from the air that has entered the dehumidifier, another fan blows the dry air back out into the room.
This process continues in a cycle, continuously lowering the average humidity in the crawl space.
If your crawl space dehumidifier has a collection tank, there will be a float that activates a cut off when the tank is full.
This type will need to be emptied regularly. If it is hooked up to a hose, it can run continuously with no intervention.
What Do You Look For In The Best Crawl Space Dehumidifiers?
No matter which technology you’re considering for a crawl space dehumidifier, you should know about the factors that separate the average from the great.
Reputable manufacturers should quote these specifications, and that should make it easy for you to compare them and make the most informed decision.
Dehumidifying Footprint
This is typically measured in square feet, and gives a rough indication as to the maximum area that the unit will be effective on.
For example, if your crawl space is 1500 square feet, but your dehumidifier is rated for 1000 square feet, it will constantly be working at maximum load, and will likely never catch up and take control of the humidity in the space
Tank Size
This is particularly important for anybody who does not have a run off or drain to have their dehumidifier empty to.
The tank size denotes how long the unit will run for without needing to be emptied.
So, if you have a unit with a 7 gallon per day tank, and a 10 gallon tank, you may end up having to empty it daily as most dehumidifiers have an auto shut off when the tank is full.
The larger the capacity, the better, but remember, a large tank full of water is heavy and potentially difficult to get out of the crawl space.
If you don’t want to intervene regularly, consider setting up arrangements for a hose and drain.
Unit Dimensions
As many of the industrial type crawl space dehumidifiers are extremely heavy given their size, this should be considered before purchase.
This about how you will get it into and positioned within the crawl space. If the unit is tall, you will need to think about whether it will actually fit inside the space.
Safety Features
As we mentioned above, good crawl space dehumidifiers should have safety features like auto shut offs for instances when collection tanks are full.
This makes sense, because having water overflowing into your crawl space is likely worse than having the humid atmosphere you were trying to get rid of.
Timers are another great safety feature that allow you to run the unit only for certain portions of the day, not only does this reduce the risk of overheating and potential fire, but it also helps to conserve electricity.
Finally, we suggest looking for a unit that has an easy-to-read display.
By definition, you’re probably in a dark, tight spot when working with your dehumidifier so a straightforward display can really make a difference!
Warranty
It’s definitely worth taking the time to find crawl space dehumidifiers from brands that clearly stand behind their products.
What better way for a manufacturer to show trust in their product than to offer a generous warranty?
This will give you the peace of mind you need, especially if you’re considering one of the more expensive industrial style dehumidifiers.
Best Crawl Space Dehumidifiers Reviewed
Aprilaire E70 Pro Dehumidifier
Check on Amazon
Our coveted best overall title went to this fantastic crawl space dehumidifier from Aprilaire.--break--It’s a rock solid unit that packs huge power into a compact shell.--break--It boasts a 70-pint (9-gallon) per day water removal rate and a 2800 square foot coverage area, which is great power! It has a convenient front mount panel, giving easy access to controls whenever settings need to be adjusted.--break--The display is simple, but shows all the information you need.--break--This is a quality, American made dehumidifier backed by a 5 year warranty.--break--The internal coils are made from corrosion resistant aluminum, and will work well for years to come.--break--The finish is a muted grey color, and it does come with leveling feet so you can keep it perfectly horizontal across a range of floor angles and conditions.
Pros
- Includes drain hose--break--2800 Square foot footprint--break--70 Pints per day removal capacity
Cons
- Some users thought the fan was loud--break--Heavy (56lb)
Dri-Eaz F413 Revolution LGR Dehumidifier (High End Pick)
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If you’re looking for a high end, high performing dehumidifier for your crawl space, you should consider the Dri Eaz F413 Revolution.--break--This is a serious unit, with a monster removal rate of up to 80 pints (17 gallons) per day depending on the temperature.--break--It has a heavy duty rotomolded polyethylene shell, so it can take some serious knocks, too.--break--The easy to use panel shows a wealth of information, including inlet and outlet temperatures, relative humidity, and run time.--break--It’s a heavier unit, but is relatively easy to transport using its integrated carry handle system.--break--In addition to its dehumidifying prowess, this unit also boasts a strong pump capable of sending water up the drain hose up to 20 feet above the level of the dehumidifier.
Pros
- Incredible performance--break--25 Foot power cord--break--Durable shell
Cons
- Struggles to remove moisture below 70 degrees Fahrenheit--break--Price
AC Infinity AirTitan T8 Ventilator Fan (Best Budget Pick)
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Our best value pick was the only ventilator style dehumidifier on the list, the AC Infinity AIRTITAN T8.--break--Given its low price, this is a strong performer.--break--It’s made from heavy duty stainless steel and boasts an IP-44 rating, making it highly resistant to dust and liquids.--break--It has a smart programming function that provides active temperature and humidity monitoring, and the fan speeds can be programmed to react to changes in temperature and humidity, too.--break--This is a truly heavy duty ventilator fan, the fan bearings are rated at 67,000 of use, and the motors run on pulse width modulation to maximize airflow and reduce noise and energy use.--break--The display is large and easy to read, and best of all, it’s a plug and play solution that requires no maintenance.
Pros
- Price--break--Sleek design--break--Assists in radon reduction
Cons
- Requires space to mount in an outside wall--break--Extremely humid spaces may require the installation of multiple units
AlorAir LGR Compact Dehumidifier
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Another excellent option on the list is this industrial standard unit from Alorair.--break--This crawl space dehumidifier works over a wide range of temperatures - from 33 degrees F to 104 degrees F.--break--It has an auto-defrosting function that can really come in handy if you live in a colder climate.--break--It’s capable of removing 10.6 gallons per day, and has a built in pump to move any water it removes to a disposal area. --break--This model is completely waterproof, so if your crawl space is prone to significant leaks or flooding, this dehumidifier is a great option.--break--The electrical safety of this device is backed by independent test lab Intertek, where after going through a series of standardized tests (and passing them all), it was granted cETL certification.--break--Its coils are made from rare earth alloys, giving them a superior lifespan compared to standard materials.--break--What’s more, Alorair supplies this with a 5 year warranty, so you can be confident that you’re buying a reliable product.
Pros
- Auto defrosting--break--Works on standard 115v voltage--break--cETL Certified for Safety
Cons
- Display screen can be hard to read--break--Hose pump strength less than other models tested
Waykar Dehumidifier
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This model from Waykar is a standard style dehumidifier, but because of its massive footprint, it should be able to handle a crawl space with ease.--break--It is rated to 4,500 square feet, and can remove up to 9 gallons of water from the air in your crawl space each day.--break--It features built in wheels for ease of transport, and the fan is exceptionally quiet.--break--The touch control display is impressive, giving lots of vital information about the atmospheric conditions.--break--With this unit you get a 24 hour timer, and automatic shut off/switch on features when the tank is full and empty respectively.
Pros
- Excellent safety features--break--Great design--break--Child lock setting
Cons
- Not as rugged/durable as industrial models--break--Tall height may prevent use in tighter crawl spaces
Final Thoughts On Crawl Space Dehumidifiers
Dehumidifiers are a vital appliance in any home with a crawl space.
You may not even feel that the air needs to be dehumidified in your crawl space, but run any of these 5 units down in yours for 48 hours or more and you will be amazed at how much moisture they can draw out of the atmosphere.
Controlling the humidity can prevent serious damage to your home, and even reduce the possibility of viral transmission as drier air does not provide the right kind of environment for viruses and bacteria to breed, grow and spread.
In this day and age, that’s a benefit everybody can use.