The crawl space is a little known part of the house that elevates your home off the ground and is a popular place to conveniently hide unsightly equipment like ductwork, plumbing, electric wiring, and more. At typically around 1 to 3 feet high, just high enough for someone to crawl inside, it might sound cozy. In reality, however, crawl spaces are damp and dark breeding grounds for mold, mildew, and bacteria.

One of the easiest ways to combat these conditions is to use a dehumidifier. Dehumidifiers are incredibly effective at reducing humidity levels in your crawl space. In this article, we’ll show you the best crawl space dehumidifier models in the market and highlight all the features that make them worthwhile additions to your home.

  • Capacity: 80 pints/day
  • Covers up to 7000 sq. ft.
  • Operating temperature: 33°F to 100°F
  • Built-in humidistat to display temperature and humidity conditions
  • Compact makes it easy to transport, hang, and position
  • Lifetime limited warranty

  • Capacity: 70 pints/day
  • Covers up to 3800 sq. ft.
  • Operating temperature: 50°F to 104°F
  • Automatic dehumidification
  • Horizontal orientation for easy crawl space installation
  • 5-year warranty

  • Capacity: 134 pints/day
  • Operating temperature: 40°F to 100°F
  • Compact makes it easy to transport, hang, and position
  • Automatic pump out feature allows continuous operation
  • Automatic humidistat to set and maintain desired humidity
  • Lifetime limited warranty

  • Capacity: 90 pints/day
  • Covers up to 3400 sq. ft.
  • Operating temperature: 49°F to 95°F
  • Dual exhaust outlets thorough air distribution
  • Horizontal orientation allows for easier installation
  • 6-year full warranty

  • Capacity: 120 pints/day
  • Covers up to 1300 sq. ft.
  • Lowest operating temperature: 33.8°F  to 104°F
  • Automatic humidistat control
  • Easy handling and installation
  • 5-year warranty


If you’re in the market for a powerful crawl space dehumidifier, then look no further than the Dri-Eaz F413. Using a refrigerant system, it’s able to cover up to 7000 sq. ft. and to extract a whopping 80 pints of moisture per day. This compact dehumidifier is housed in a durable polyethylene frame that’s backed by a lifetime warranty from Dri-Eaz.

The biggest drawback to purchasing the F413 is that it’s incredibly expensive. Considering its features, performance, and durability, this is no surprise. There are, though, an alarming number of reports from users that the F413 leaks, which is unacceptable considering how much the unit costs. Despite these flaws, however, there’s no denying that the F413 is one of the best dehumidifiers for your crawl space or basement. As expensive as it is, you can rest easy knowing that the F413 will repay you in durability, reliability, and performance. You get everything from automatic humidity control to automatic draining to extreme temperature operation.

Pros

  • High daily moisture reduction capacity
  • Large coverage area
  • Automatic humidity control
  • Compact lightweight
  • High air flow filter traps air pollutants
  • Automatic pump
  • Lifetime warranty
  • Low temperature (as low as 33°F) operation

Cons

  • Expensive
  • Leaking issues

The Aprilaire 1830 is easily the most popular crawl space dehumidifier. This model is a whole-house dehumidifier that you can connect to your HVAC system to service your entire home. It can cover up to 3800 sq. ft. and extract up to 70 pints per day.

Although cheaper than most models on this list, the 1830 still isn’t what you’d call affordable. One of the other, more notable flaws is that the lowest temperature at which the 1830 can operate is 50°F which can be problematic if you’re planning to use it during the cooler seasons. It’s also reportedly loud, and replacement parts for it are difficult to find.

Fortunately, the 1830 makes up for it in solid performance and high quality construction. Furthermore, despite its limitations with operating temperatures, it comes with automatic defrost control to prevent ice build-up. With its MERV-8 filter, you can rest assured you have only the cleanest, odor-free air in your crawl space. As with most Aprilaire products, the 1830 is durable, effective, and easy to use.

Pros

  • High daily moisture reduction capacity
  • Large coverage area
  • Durable
  • Automatic humidity and defrost control
  • Easy to install, use, and maintain
  • MERV-8 filter removes pollutants

Cons

  • Expensive
  • Cannot operate at temperatures lower than 50°F
  • Loud
  • Short drain hose
  • Hard to find replacement parts

The PHD 200 is another top-performer from Dri-Eaz that capable of extracting a whopping 134 pints per day. It also uses a refrigerant system and is designed similarly to the F413. Its polyethylene frame is also backed by a lifetime warranty and its parts are backed by a 6-year warranty.

There are a number of complaints from users regarding its durability, which is a surprise considering the price of this model. In addition to that flaw, the PHD 200 cannot operate at extreme temperatures. With all things considered, though, the PHD 200 is still a solid choice for a crawl space dehumidifier. Aside from its exceptional specifications, it also comes with an automatic pump, automatic humidistat, and mesh air filter that all combine to give you moisture-free and clean air.

Pros

  • Lighter and smaller than standard humidifiers
  • High daily moisture reduction capacity
  • Automatic pump
  • Automatic humidity control
  • Mesh air filter removes pollutants
  • Quiet operation
  • Lifetime warranty

Cons

  • Expensive
  • Durability issues
  • Cannot operate at temperatures higher than 40°F

The Advance90 is one of the best-selling models from one of the most reputable brands in the industry, Santa Fe. This model is capable of covering a massive 3400 sq. ft. of space as well as being able to extract 90 pints per day (thus the name).

Like most crawl space dehumidifiers, the Advance90 does not come cheap, although it is notably cheaper than its Dri-Eaz counterpart the F413. Another notable flaw is that it cannot operate at temperatures lower than 49°F, which means you can’t have it running during the colder months. Overall, however, the Advance90 is definitely one of the best dehumidifiers on this list and comes quite close to our top pick. It has a MERV-13 filter capable of removing microscopic air pollutants to provide the cleanest and freshest air for your crawl space through reliable performance and the promise of a long, reassuring warranty.

Pros

  • High daily moisture reduction capacity
  • Large coverage area
  • Long warranty
  • MERV-13 filter effectively traps air pollutants
  • Energy efficient (Energy Star qualified)
  • Quiet operation
  • Customizable options with accessories (purchased separately)

Cons

  • Expensive
  • Cannot operate at temperatures lower than 49°F


The AlorAir Sentinel HD55 is the cheapest humidifier on this list but it’s by no means inferior. It’s rated to cover up to 1300 sq. ft. of space at an extraction rate of 120 pints per day. For its price range, the HD55 is definitely unrivaled in terms of performance.

Unfortunately, the HD55 has been the subject of several negative reviews from users claiming it isn’t as durable as its peers. Furthermore, despite its claim to be able to remove up to 120 pints of moisture per day, the HD55 seems to struggle removing moisture and lowering humidity levels in the areas it’s placed in. While the validity of the claims remains to be seen, there’s no denying that the HD55 is a worthy investment for homeowners looking for a reliable, high-quality, entry-level dehumidifier for their crawl space. Aside from being more affordable than most, the HD55 gives you more bang for your buck with its remote control, automatic humidity control, timer function, and extreme temperature operation.

Pros

  • Cheaper than other models
  • High daily moisture reduction capacity
  • Large coverage area
  • Remote control
  • Automatic humidity control
  • Timer function
  • Long warranty
  • Low temperature (as low as 33°F) operation

Cons

  • Durability issues
  • Water extraction issues

Crawl Space Dehumidifier Buyer’s Guide

The Importance of a Dehumidifier

Essential for hiding the “guts” of your home (i.e.: HVAC equipment, ductwork, plumbing, electric wires, and more), crawl spaces allow easy access to them when repairs and maintenance work need to be done. They can also be used to store old, infrequently used items.

Because crawl spaces house drain pipes and are situated so close to damp soil, they’re more prone to high humidity levels. This is especially true when said pipes are leaking and the crawl space vents are open, potentially bringing in more humid air from the outside. Unfortunately, these dark and moist conditions are optimal for the growth and proliferation of mold, mildew, and bacteria. These conditions also promote wood rot (caused by fungi) as well as degrade the air quality in the space.

Crawl space dehumidifiers help you maintain the right humidity level in your crawl space and prevent mold growth as well as protect any items you may have there from unwanted moisture. Crawl space dehumidifiers are powerful devices used to extract massive amounts of moisture from crawl spaces continuously on a daily basis. They often look a little rugged compared to room dehumidifiers because they’re intended to be kept out of sight as well as withstand harsh conditions like extremely low temperatures.

The Different Types of Dehumidifiers and How They Work

Desiccant Dehumidifiers

A desiccant is a hygroscopic substance that is widely used for drying purposes. Desiccant dehumidifiers work by running moist air through a rotor that has a moisture adsorbent desiccant material. Once the water is removed from the air, the dry air can then be released back out into the vicinity.  Water collected from moist air is removed by heating, and the vaporized moisture can then be ducted out of the house/building.

Refrigerant Dehumidifiers

Most of the popular dehumidifiers in the market are refrigerant dehumidifiers, which work by drawing moist air into the dehumidifier and passing it over a cold evaporator coil. The coil cools the air past its dew point (the atmospheric temperature below which water droplets begin to form) and causes condensation to occur. This water collects on a pan and can be removed manually or purged through a hose directly connected to the dehumidifier. The newly dried air is then released back into the room.

Key Characteristics of Crawl Space Dehumidifiers

When it comes to choosing the right dehumidifier for your home, it’s important to keep these key characteristics in mind:

Extraction Rate

The extraction rate for a dehumidifier measures how much water it can extract on a daily basis. This is often measured in pints per day (PPD). Generally, refrigerant dehumidifiers are able to extract larger amounts of water as compared to desiccant dehumidifiers and are particularly more useful during flood restoration when materials require more rapid drying. Of course, extraction rates vary from brand to brand and from model to model so it’s best to do a little research beforehand.

Area Coverage

Area coverage simply measures how big of a space the dehumidifier is able to service. This changes dramatically depending on the relative humidity of the crawl space, the temperature, and the quality of sealing. A dehumidifier will be able to maximize its area coverage when the crawl space is very tightly sealed.

Operating Temperature

This is a very important characteristic that you will have to consider when purchasing a dehumidifier as the operating temperature directly affects how your dehumidifier will work. Desiccant dehumidifiers, in general, are able to withstand colder temperatures than refrigerant dehumidifiers because refrigerant dehumidifiers struggle to reach the required dew point during the cooler seasons. There are certain brands of refrigerant dehumidifiers, though, that are able to operate at temperatures as low as 33°F, so it’s best to do a little research before you buy.

Running Costs

Generally, dehumidifiers don’t cost much to operate. You can expect to spend $15 to $35 per month on electricity, but this can go upwards of $50 if your dehumidifier is running continuously. Between the two types of dehumidifiers, refrigerant dehumidifiers consume less energy than desiccant dehumidifiers.

Noise

Because refrigerant dehumidifiers use compressors to run, they’re typically louder and noisier than desiccant dehumidifiers. Considering crawl space dehumidifiers are tucked away in your crawl space, however, the noise shouldn’t be too loud or distracting.

Size/Weight

Crawl space dehumidifiers nowadays are available in more compact sizes, but despite their small appearance they can nevertheless be quite heavy. This is particularly true for refrigerant dehumidifiers which have heavier components. Regardless of the weight, your dehumidifier should be small enough to comfortably fit in your crawl space.

Crawl Space Dehumidifier Care and Maintenance

Compared to other types of home appliances, crawl space dehumidifiers often need very little maintenance, but they aren’t maintenance-free. There are still necessary steps you need to take in order to keep your dehumidifier in the best shape.

Ensure Proper Placement

One of the first things to determine when bringing home your crawl space dehumidifier is where to place it. To get the most of a dehumidifier, you have to place at least 6 inches away from the walls to ensure proper airflow. Furthermore, it’s best to keep the crawl space as tightly sealed as possible to keep the dehumidifier running optimally. Open windows/doors can make the dehumidifier work twice as hard to remove the moisture in the room and thus can lead to higher electricity bills.

Adjust the Humidistat

All dehumidifiers come with a humidistat that allows you to set the humidity to your desired level. Ideally, the Environmental Protection Agency (EPA) recommends keeping indoor humidity levels to 30% to 50%. The same is true for your crawl space. To keep your dehumidifier from working too hard, make sure you adjust the humidistat to the right level and avoid setting it at a very low humidity level.

Periodically Replace the Filter

Most dehumidifiers come with an air filter to remove unwanted air pollutants such as allergens and dust. The filter protects the dehumidifier as well as ensures the air it releases is as clean and healthy as possible. Different models use different types of filters, so it’s best to always check the manufacturer’s instructions or user manual to find out how often you should change out your dehumidifier’s filters.

Check the Drain

Crawl space dehumidifiers often have hoses that allow the collected water to drain automatically so you don’t have to worry about doing it yourself. It’s important, however, to ensure that there are no blockages or airlock in the drain system to keep the dehumidifier running efficiently. Otherwise, a qualified service professional may need to repair it.

Check Coils

A common problem with dehumidifiers is that they’re prone to frost or ice build-up especially when they’re running in cooler conditions. This will interfere with how the dehumidifier operates. If you think your dehumidifier is suffering from this problem, turn off the dehumidifier and unplug it so that you can safely access the internal system. Be warned, though, that opening your dehumidifier or taking apart may void your warranty. In these cases, it’s best to check for defrosting tips in the user manual or contact the manufacturer of your dehumidifier.

You can also place the dehumidifier in a warm place to hasten the defrosting process. Another way to curb this problem altogether is to purchase a dehumidifier unit with an automatic defrost function that shuts the compressor off when it detects ice build-up. The fan keeps running to melt the ice build-up and, once all the ice has melted, the compressor turns on again and operation resumes as normal.

Clean air intake and exhaust grills

As with any home appliance that solves air quality problems, the air intake and exhaust grills of the dehumidifier need to be cleaned regularly to keep it running efficiently. You can do this by running a vacuum brush over the grills at least once per season.

Avoid Short-Cycling

Avoid switching on and turning off your dehumidifier at short intervals. Doing this can cause the compressor to overheat and potentially trip your circuit-breaker. You should be waiting at least 10 minutes before switching your dehumidifier on again. This allows the pressure in the system to equalize and prevents damage to the compressor.

FAQ

Does a dehumidifier help prevent mold growth in our crawl space?

Yes, it does. Dehumidifiers effectively remove moisture from a given space to maintain optimum humidity levels. Without high levels of moisture, mold and mildew cannot grow. This is why it’s important to have a dehumidifier in areas where you want to inhibit the proliferation of mold, mildew, and bacteria that thrive in humid environments.

How loud can I expect a crawl space humidifier to be?

The crawl space dehumidifiers on this list are quite powerful so it’s no surprise that the fans and airflow can make quite a loud noise. Generally, crawl space dehumidifiers are around 60 dB loud which isn’t too bad especially considering their tucked away in your crawl space.

What is the ideal humidity level for a crawl space?

The ideal humidity level for the crawl space is the same for the rest of the house: 30% to 50%. This is the humidity level recommended by the EPA and is the level at which mold spores are unable to grow. For more information on maintaining the ideal humidity levels at home, read our guide here.

Final Thoughts

Crawl spaces deserve care and attention, particularly since they’re prone to high humidity thanks to their close proximity to the soil. These conditions bring about problems such as mold and bacterial growth that you’ll want to remedy before it gets out of hand. One of the easiest ways to address these issues is to use a dehumidifier in your crawl space.

Our top pick for the best crawl space dehumidifier would definitely be the Dri-Eaz F413 Revolution LGR Dehumidifier. All that you pay upfront will be repaid in powerful, reliable, and convenient performance. The F413 does everything you need it to do at an unrivaled level and makes using it extremely hassle-free and convenient.

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