Depending on where you live, many homes might sit upon crawl spaces instead of basements or traditional foundations. These spaces are dark and dusty, and air quality isn’t always at its finest. If humidity climbs (which it often does) in a sealed crawl space, the moisture can cause mold, mildew, rot, and other difficult-to-handle issues.
Instead of letting this moisture-rich space grow mold and bacteria, call upon the best crawl space dehumidifier for your solution. The machine hangs from the floor joists in a crawl space, pulling the humid air, removing the moisture, and sending the fresh, dry air back out. If your crawl space is humid, keep reading to learn more.
- BEST OVERALL: AlorAir Commercial Dehumidifier 113 Pint
- BEST BANG FOR THE BUCK: Waykar 155 Pints Commercial Dehumidifier
- UPGRADE PICK: ALORAIR Basement/Crawlspace Dehumidifiers 198 PPD
- BEST FOR LARGE SPACES: Aprilaire – 1830Z 1830 Pro Dehumidifier
- BEST FOR SMALL SPACES: ALORAIR Basement/Crawl Space Dehumidifiers 120 PPD
What to Consider When Choosing the Best Crawl Space Dehumidifier
No one wants mold or mildew growing under their feet, and the best crawl space dehumidifier will help ensure it doesn’t. While these dehumidifiers work very similarly to indoor and basement units, there are some differences and points to keep in mind when shopping for one. The following sections will delve into the top considerations to think about.
Choosing the proper size dehumidifier is critical to ensure it’s able to handle the task at hand. If it’s too small, it won’t be able to remove humidity from an entire crawl space. If it’s too large, it’ll use more electricity than necessary and cost too much upfront. Here are some points to consider.
- Square footage: Most crawl space dehumidifiers clearly describe the amount of space they’re able to cover. They range from as low as a few hundred square feet to several thousand.
- PPD AHAM: Along with square footage, shoppers will notice a PPD (pints per day) AHAM value, which describes how many pints of water the dehumidifier can remove per day in a specific condition. These conditions are set by AHAM (Association of Home Appliance Manufacturers), and they’re 80 degrees Fahrenheit and 60 percent relative humidity.
- Saturation: Many dehumidifier manufacturers also describe how many pints their units can remove in saturated conditions. This value is often quite higher but lacks the same level of standardized testing as PPD AHAM.
Humidistats are an important feature to look for in the best crawl space dehumidifier. They allow the user to set the level of humidity for the dehumidifier to maintain. The unit will run when the humidity levels climb above the setting and shut off when they drop below it. Why are they important? Consider these points:
Even the best crawl space dehumidifier uses quite a bit of electricity. Allowing a unit to run constantly will make the power company very happy and your bank account less so. A humidistat will throttle the machine’s electrical output so it only runs when it needs to.
Crawl spaces aren’t people-friendly places. They’re dark, dirty, and very tight. Heading under to check humidity levels and manually activating the dehumidifier would be a nightmare. The humidistat takes care of it for you.
Crawl spaces are popular in many areas across the country, and many of those areas get very cold in the winter. Leaving a crawl space dehumidifier exposed to the elements can freeze the condensation coils and destroy the machine. For this reason, a defrosting system is essential.
The defrosting system maintains a warmer temperature within the dehumidifier. This prevents cold air from freezing the condensed water or coils, allowing the unit to run much longer. Even in areas where temperatures aren’t likely to freeze, it can be an important feature. In fact, it only takes one time for a freeze to break a coil.
Like household dehumidifiers, crawl space dehumidifiers collect the water they remove from the air. Unlike the household models, heading to the crawl space twice a day to remove a tank isn’t possible or practical. Instead, these models drain, but some models or scenarios require condensate pumps to work effectively.
Units equipped with condensate pumps push the water wherever it needs to go. Whether through a long run of hose or a drain that’s only accessible above the unit, a condensate pump will push the collected water out of the crawl space so you don’t have to crawl under and empty the tank.
There are a few other features that might make a particular model the best crawl space dehumidifier for your needs.
- Filtration: Many units feature filters that help collect dust and other particles, allowing the unit to last longer and the space underneath the home to stay fresher.
- Remote control: Some of the best crawl space dehumidifiers feature remote controls that allow the user to adjust the humidity levels and turn the machine on and off without entering the crawl space.
- Noise: Some units are louder than others, and since a dehumidifier typically attaches from the floor joists in the crawl space, that noise can travel into the house a bit. If this is an issue, you might be able to install your dehumidifier on concrete blocks, though you should follow manufacturer recommendations.
- Memory or auto restart: Many of the most humid months bring thunderstorms with them, which often knock out the power. Some models with auto-restart or memory functions will remember their settings prior to the power outage and continue working where they left off.
Our Top Picks
There’s quite a bit to know about choosing the best crawl space dehumidifier. Between choosing the right size, deciding whether a pump is necessary, and picking convenience options like remote controls and filters, there are a lot of decisions. The following list aims to streamline the shopping process a bit, as it’s a collection of some of the best crawl space dehumidifiers on the market. Be sure to keep the top considerations in mind when comparing these products.
AlorAir’s Commercial Dehumidifier is worth checking out for anyone hunting for a medium-capacity unit to fix their crawl space moisture issues. This model features a 113 PPD capacity in saturation conditions and 53 PPD AHAM conditions, making it suitable for spaces up to 1,200 square feet (which includes most residential crawl spaces). It comes with a filter to prolong the life of the unit, which is easy to access from the side of the machine.
Besides its capacity, this gravity-draining unit has plenty of desirable features. Among those features are an automatic defrost setting to protect the coils from freezing and memory restart, allowing this unit to pick up where it left off after a power outage. This model from AlorAir is also compatible with a remote control for easy settings and readings, though it is a separate purchase.
Those looking for all the features of an expensive crawl space dehumidifier without the massive price tag should check into Waykar’s Commercial Dehumidifier. This model is capable of removing 155 pints of water from the air each day in saturation conditions, so it’s able to cover even larger crawl spaces.
This gravity drained model from Waykar has a lot to offer. The Commercial Dehumidifier has a programmable humidistat that allows the user to dial in the proper moisture level, as well as a digital remote control for convenient programming. A removable and washable air filter keeps dust from clogging the coil. An automatic defrost setting will kick on as needed to keep the coils from freezing. If the power goes out, the Waykar features an automatic restart, allowing it to get back to work when power is restored.
Large spaces with serious moisture issues might require a bit more power, and a heavy-duty upgrade unit like AlorAir’s Basement/Crawlspace Dehumidifier might be the way to go. This model features a 198 PPD rating in saturated conditions, giving it enough power to cover spaces up to 2,600 square feet.
This model from AlorAir isn’t just capable of handling larger spaces, it also has convenience features like automatic defrost and compatibility with a remote control (though it’s a separate purchase). If the power goes out, the automatic restart will kick on and begin dehumidifying without user input. Also, this unit comes with a condensate pump already installed, allowing users to remove water with ease, pumping the water away instead of relying solely on gravity. This makes for more installation options even in awkward crawl spaces.
Massive crawl spaces and other areas that require dehumidifying can benefit from a powerful unit like this model from Aprilaire. The 1830Z 1830 Pro Dehumidifier can remove up to 70 pints of water per day at AHAM standard levels in spaces up to 3,800 square feet.
The 1830Z 1830 Pro is a gravity draining unit with digital controls on the top or front of the unit. Once set, users can leave this dehumidifier to its own devices as it turns on and shuts off automatically according to the humidity levels in the air. This model comes with a dust and particle filter, offering long life and protecting the user’s investment.
For smaller crawl spaces, large units are a waste of money and energy consumption. In those smaller areas, a unit like this one from AlorAir is worth checking out. This model features the capacity to remove up to 55 PPD AHAM from crawl spaces and other areas up to 1,300 square feet, with a maximum PPD in saturation of 120. This smaller dehumidifier is also Energy Star certified, making running it more affordable.
This model has plenty of automatic features adding to its appeal. It has an automatic defrost mode to keep the coils from freezing during colder weather, as well as a removable filter to keep those coils clean. The AlorAir features a gravity drain as well as compatibility with a remote control for maximum convenience (though it is a separate purchase). Also, should the power go out, this unit will remember its settings and continue to dehumidify when the power comes back.
FAQs About Crawl Space Dehumidifier
Even with that extensive background on choosing the best crawl space dehumidifier, there might be some additional questions popping up. This section aims to provide answers, as a collection of some of the most frequently asked questions about crawl space dehumidifiers.
Q. Can I use a regular dehumidifier in a crawl space?
Technically, you could, but they aren’t built for the rigors of crawl space life. Regular dehumidifiers’ coils aren’t durable, they rarely feature defrost functions, and most have tanks that require emptying. Also, crawl space dust is sure to limit an indoor unit’s lifespan.
Q. At what temperature should I set my dehumidifier in a crawl space?
You shouldn’t set a crawl space dehumidifier to a temperature, but rather a moisture level. As a general rule, you want to keep that space under 55 percent humidity, so setting the unit to 50 percent should do the trick.
Q. Where should I place my dehumidifier in a crawl space?
You’ll want to set up the dehumidifier in an area where it can draw in moist air and push out dry air without obstruction. It’s best to set it up in the center of the crawl space.
Q. How long will my crawl space dehumidifier last?
Dehumidifiers don’t require much maintenance other than cleaning or changing the filter every 6 to 12 months. If maintained properly, you can expect your dehumidifier to last around 5 years.