One of the most common uses for a dehumidifier is to prevent mold and mildew in a damp basement. To dehumidify a large basement (up to 1,400 square feet), you'll need a dehumidifier that can remove 70 pints of water a day and can operate in temperatures below 65 degrees Fahrenheit. Automatic defrosting, which prevents ice from forming on the humidifier's condensing coils at low temperatures, is a particularly useful feature for basement use. Drainage is another important consideration. One option in basements is to connect a hose that continuously feeds water out into a floor drain, eliminating the need to empty the water collection container by hand. A few models have a pump that allows you to run the drainage hose to a sink or out a window. Noise level, by contrast, is a less important consideration in a basement than in a bedroom or living area.
We found several recommendations for the feature-rich, 70-pint Danby DDR7009REE (*Est. $210). This dehumidifier operates in basements as cold as 41 degrees Fahrenheit, keeps the coils defrosted and restarts automatically after a power outage. Other features include a digital display, a two-speed fan and a remote control. Although its 14.2-pint collection container is smaller than some, testers at the Good Housekeeping Research Institute find it particularly easy to remove and empty. However, it is also possible to set up this dehumidifier so that it drains continuously through a hose into a floor drain.
The Danby DDR7009REE dehumidifier is Energy Star-rated, but Good Housekeeping found "its energy consumption is higher than most." This may be due to the fact that the fan on this unit continues to run even after the desired humidity level is reached and the compressor turns off. However, some experts say a continually running fan is actually a good thing, because it helps keep the humidity even throughout the room and prevents mold from developing inside the unit.
The Danby DDR7009REE receives mostly positive reviews from about 300 owners posting reviews on retail sites such as Amazon.com, Sylvane.com and AchooAllergy.com. Most owners use it in a basement and say it quickly eliminates humidity and mildew. Their main complaint is that the dehumidifier's fan doesn't automatically shut off, so it creates continual background noise; however, most say that the humidifier is fairly quiet. The Danby DDR7009REE is backed by a two-year warranty -- twice the one-year warranty length we found for most dehumidifiers.
Reviewers at the Good Housekeeping Research Institute give the Comfort-Aire BHD-651-G (*Est. $250) a higher overall grade than the Danby dehumidifier. This 65-pint Comfort-Aire model is as energy efficient as the 70-pint Danby, and experts say it removes moisture well and is easy to use. Good Housekeeping notes that this machine is easy to set and forget, as it can run for more than seven hours before it needs to be emptied. On the downside, they note that it can be noisy. However, the 60 owners at Sylvane.com, who give this dehumidifier 4.5 stars out of 5 overall, generally do not find the noise level to be a problem. They also find it very effective and easy to empty. The 20 or so reviewers at Amazon.com, by contrast, are much less enthusiastic, giving the dehumidifier only 2 stars out of a possible 5, on average. We read many complaints about breakdowns within the first two years, and several reviewers note that it was difficult to get repairs under Comfort-Aire's one-year warranty. Due to the mixed user reviews for this model, we think the Danby unit is a better choice.
Another large dehumidifier that gets high marks from Good Housekeeping editors is the 65-pint Sunpentown SD-65E (*Est. $215). Reviewers say it is very effective at removing moisture, and the filter is easy to clean. However, its energy efficiency is unimpressive and its noise level is a bit high. Another professional test has similar findings: The Sunpentown gets excellent ratings for moisture removal and accurate humidity readings but is noisier than most. Its performance at temperatures below 50 degrees is also below average. We found roughly 130 reviews for the Sunpentown SD-65E at Amazon.com, with an overall rating of 4.5 stars. Owners find it effective and easy to use, and they like the auto-restart and continuous-drainage features. Some say that it can be excessively loud, but only on the higher of its two fan settings.
For those with small basements, we found good overall ratings for the 50-pint GE ADER50LQ (*Est. $235). This dehumidifier can operate at temperatures as low as 41 degrees, and it has digital controls, three fan speeds, an auto-restart feature and a continuous-drainage option. In professional tests, this dehumidifier gets excellent scores for moisture removal and energy efficiency. However, its humidistat accuracy and noise level are only so-so, and its performance at low temperatures is unimpressive.
We did not find many user reviews for this specific model, but we found about 75 for an older version at ABT.com and more than 50 for an equivalent model at Walmart.com. Both of these units get high ratings from users, who say they are effective and easy to use. Most also say that the dehumidifier's noise level is acceptable. The most common complaint is that the 17.5-pint water tank can be tricky to empty. We also read several complaints about breakdowns for the Walmart version.
Another 50-pint model that does fairly well in reviews is the Kenmore 511100 (*Est. $210), formerly known as the Kenmore 50501. In a 2011 Washington Post article on choosing the best dehumidifier, this model is recommended for its Microban-coated water bucket, which helps control microbial growth, and its cycle timer, which can switch the unit off and on throughout the day. However, this dehumidifier has not been subjected to any actual testing, so our only source of information about its performance is the user reviews at Sears.com (the only site that sells Kenmore appliances). The Kenmore 511100 gets an overall rating of 4 stars out of 5 from more than 80 owners, who find it effective, nice looking and easy to use. They also like the electronic controls and continuous-drain feature. However, some complain that it is noisy and the 19.4-pint water bucket is difficult to empty.
The Santa Fe Classic (*Est. $1,535) is in a class all its own. This high-end dehumidifier is capable of extracting an impressive 110 pints of water from the air in a 24-hour period, which the manufacturer says will cover a 2,500-square-foot basement. Instead of a standard fan, this unit has a blower capable of moving 275 cubic feet of air per minute, and its energy efficiency exceeds Energy Star standards by a significant margin. Another feature that helps it earn a perfect 5-star rating at AllergyBuyersClub.com is a dual filter that reviewers say is extra effective at removing dirt, dust and other allergens from the air. Both the foam filter and pleated fabric filter should be cleaned every six months, though both will need replacement after a couple of years. The warranty on this dehumidifier covers the entire unit for one year and the refrigeration system (compressor, evaporator and condenser) for five years.
This well-reviewed dehumidifier is not without its drawbacks, however. For one, the Santa Fe Classic dehumidifier doesn't have a collection tank; it must be connected to a floor drain with the included 8-foot hose. This dehumidifier is also quite large and heavy: it measures 3 feet tall, 20 inches wide and 17 inches deep and weighs 110 pounds. This could make moving the unit a challenge for some. Also, the Santa Fe Classic will not operate at temperatures below 53 degrees, while some units can go as low as 41 degrees. Finally, the editors of AllergyBuyersClub.com note that the Santa Fe Classic dehumidifier is not particularly quiet, though an optional muffler kit is available to reduce noise. This dehumidifier can also be installed in a utility room and ducted to dehumidify an adjacent room, but this feature requires professional installation.
Owner reviews for the Santa Fe Classic dehumidifier are quite positive. More than 125 owners posting at DehumifierExperts.com (a retail site) give it a rating of 4.7 stars out of 5, saying it does an exceptional job of eliminating moisture and mustiness. The dehumidifier gets similar ratings from more than 80 owners at Sylvane.com. They say it's easy to set up and made a dramatic difference in the basement after just a few hours. Some add that although it's expensive, it costs less in the long run than buying a $250 dehumidifier that isn't really up to the job and then having to replace it every year. Their biggest gripe is that getting repairs is difficult since there are so few repair shops that service this brand, and shipping it back to the manufacturer is prohibitively expensive.
If you need to place a dehumidifier in a room where there is a lot of activity, noise is going to be a more crucial buying consideration. The size of the collection container is also important, as it's not likely you'll want to hook up an unsightly drainage hose. A dehumidifier with a large collection container will need less frequent emptying than a smaller one, but the full bucket will be heavy. A timer may also be important, if you want to delay the start time or set a specific stop time.
Editors at AllergyBuyersClub.com say the Frigidaire FAD704DUD (*Est. $220) can effectively dehumidify up to 1,400 square feet with minimal noise. This dehumidifier is the top performer in one professional test, with excellent scores for moisture removal and energy efficiency and very good scores for humidistat accuracy and noise level. (Its cool-room performance is subpar, but for use in a living space, this shouldn't matter.) The dehumidifier's 17-pint reservoir loads from the front of the unit and has a small window so you can see when it is nearing capacity. The dehumidifier does not come with a hose for continuous drainage, but it is possible to hook up a standard garden hose for this purpose. The Frigidaire dehumidifier has a washable, antimicrobial filter, a timer and automatic restart; however, it lacks automatic defrosting, which makes it better suited for living spaces than for chilly basements.
Consumers also like the Frigidaire FAD704DUD. It is the top dehumidifier at Amazon.com with an average of 4 stars out of 5 from roughly 335 owners, and it gets even higher overall ratings at ABT.com and Walmart.com. Reviewers praise the dehumidifier's performance, quiet motor and efficiency, although many say that attaching a hose for continuous drainage does not work properly. Two owners at Amazon.com say they had problems obtaining repairs under warranty, however.
The 50-pint Frigidaire FAD504DUD (*Est. $200) has the same features as the 70-pint Frigidaire. In professional tests, it gets lower scores for energy efficiency than the larger model, but its cool-room performance is better. This dehumidifier receives mostly positive reviews from about 200 reviewers at Amazon.com and Walmart.com. Like the larger Frigidaire, it earns praise for its quietness and effectiveness, but users gripe that draining it with a hose doesn't work. However, some note that you can fix this problem by either tilting the unit backward or plugging the hole in the top of the water reservoir. This dehumidifier is covered by the same warranty as the larger model; we did not read any reports of problems with warranty service.
The 50-pint Danby DDR5009REE (*Est. $210)
Dehumidifiers for crawl spaces have a special set of features. First, they must be short enough to fit into a crawl space with a low clearance. They also need to operate at low temperatures. Finally, they need continuous drainage, because climbing into a crawl space to empty a water reservoir every day isn't a practical option. The Santa Fe line of dehumidifiers, made by Therma-Stor, includes several models that meet these criteria, but they cost much more than a standard home dehumidifier. For the money, though, you get a powerful dehumidifier that reviewers say is built to last.
The most powerful crawl space humidifier we found in our sources is the 90-pint Santa Fe Advance (*Est. $1,275). The manufacturer says this 20-inch-tall unit can effectively dehumidify a crawl space up to 2,200 square feet. On this unit, the air intake is at one end, and the exhaust is out the top. Rather than setting a specific target relative humidity (RH), it has three settings -- dry (35 to 45 percent RH), normal (45 to 55 percent RH) or humid (55 to 65 percent RH) -- and the fan can be set to run continuously or only when it's dehumidifying. Other features include two-stage filtration, a defrost cycle and automatic restart after a power outage. One potential drawback to this dehumidifier is that it cannot run at temperatures below 55 degrees, which may make it less suitable for colder climates.
The reviewer at AllergyBuyersClub.com gives the Santa Fe Advance a perfect 5-star rating, describing it as "durable, powerful, and energy efficient." This dehumidifier also gets a 5-star rating from about 50 users at Sylvane.com and a 4.6-star rating from nearly 50 consumers at DehumidifierExperts.com. Owners say this machine is extremely effective at removing moisture, even in a huge space. Most also find it reasonably quiet. Although a couple of users say a longer power cord would be handy, we did not find any who appear to be dissatisfied with their purchase.
The smaller Santa Fe Compact Dehumidifier (*Est. $1,110)
Both these units include a drain hose that must be hooked up for continuous removal of the condensed water (there's no internal collection container). A pump is available as an option if you need to run the drainage hose vertically. Other options allow you to install a remote humidistat, hang the dehumidifier, add caster wheels or attach ductwork to the intake and exhaust. Installing these options may require the help of a professional. The manufacturer offers a comprehensive one-year warranty, but the compressor, condenser and evaporator are covered for five years.
If you need a dehumidifier for a small, enclosed space like a closet or cabinet, owners say Eva-Dry mini dehumidifiers are an effective choice. The Eva-Dry E-333 Mini Dehumidifier (*Est. $20) and Eva-Dry E-500 Mini Dehumidifier (*Est. $30) operate without batteries or electricity. Instead, these appliances use silica gel crystals that naturally absorb moisture. When the crystals have absorbed all the moisture they can, their color changes from blue to pink, indicating it's time for the unit to be plugged into an electrical outlet so that the crystals can be dried and reused. During recharging, the unit should be placed in a well-ventilated area (such as a bathroom with the vent fan on) so that the moisture isn't released back into the space. Once the crystals are dry, which takes up to 14 hours, they turn blue again.
The Eva-Dry E-333 dehumidifies an area of up to 333 cubic feet, making it appropriate for closets, cabinets and safes; the larger Eva-Dry E-500 dehumidifies up to 500 cubic feet, a good size for boats and RVs. The manufacturer says the E-333 needs recharging after 20 to 30 days, while the E-500 can dehumidify a space for 30 to 60 days. Both units can last up to 10 years and come with a five-year warranty.
The Eva-Dry E-333 and E-500 aren't covered in any professional reviews, but the larger EDV1100 gets a 3-star overall rating from the expert reviewer at AllergyBuyersClub.com, who tested it in a small bathroom. The reviewer is "impressed with how it helped with preventing mold, mildew and stuffiness," but warns that this tiny dehumidifier is not powerful enough to cover an entire room. The reviewer also notes that unlike most dehumidifiers, the Eva-Dry does not heat up the room while it is in use. The smaller Eva-Dry units receive many positive reviews at Amazon.com -- about 125 for the E-333 and 185 for the E-500.
Many owners report using the Eva-Dry to eliminate mustiness and mildew in closets, safes, cabinets and small bathrooms. Satisfied users say the Eva-Dry units are much more cost-effective than silica packets, which need to be discarded and replaced when they've absorbed all the moisture they can hold. However, a minority of owners complain that their Eva-Dry dehumidifiers didn't work at all, and some who bought the E-500 say that recharging the unit is awkward because it's too heavy to stay plugged into a wall socket without support.