What to look for in a dehumidifier
Dampness level: Dehumidifiers come in different sizes depending on how much moisture they can remove in 24 hours. Here's what size to buy based on how humid your room is:
Dampness level | Characteristics | Dehumidifier size | Room size |
Moderately damp | Musty aroma in the area during humid weather | 25-39 pint capacity | Small (closets, small bathrooms) |
Extremely damp | Always damp in the area regardless of season | 40-59 pint capacity | Medium (bedrooms, small basements, large closets) |
Wet | Visible condensation on ceilings and walls | 60+ pint capacity | Large (large basements) |
How the unit removes moisture: It will either have a built-in pump or a direct drain. A built-in pump lets you run the drain hose to a window or sink, while a direct drain funnels the water directly into a sink or drain.
Energy performance: To get maximum efficiency out of a unit, look for those that are Energy Star-certified.
Automatic or useful features: Look for a unit with an adjustable humidistat, which will automatically turn your unit on and off to maintain the preset humidity level. Other useful features, according to The Home Depot, include:
- Automatic shutoff: Turns your unit off once the tank is full
- Digital display: Shows the relative humidity level and other settings
- Filter sensor/indicator: Tells you when it's time to replace the filter
- Programmable timer: Lets you run the unit only at certain times of the day
- Auto-defrost: Keeps your unit from freezing in cold temperatures
It's also worth pointing out that many AC units have built-in dehumidifiers. If your AC unit is in your desired room, check first to see if it has a dehumidifier and whether it works well. We tested the best air conditioners.
Why we're the experts
In our first major rewrite of this guide, we consulted allergy, skincare, and HVAC experts to learn more about how a dehumidifier can help your health and what features to look for. We spoke to Kenneth Mendez, president and CEO of the Asthma and Allergy Foundation of America (AAFA); John McKeon, CEO and founder of Allergy Standards Limited (ASL); and Jeanine Downie, MD, FAAD, director of Image Dermatology PC.
Using their insights, along with our own research and knowledge of the space, we selected our dehumidifier options.
Dehumidifier FAQs
Why do you need a dehumidifier?
A dehumidifier helps maintain the optimal level of humidity in your room so it's not too humid. It reduces the growth and incidence of mold, mildew, and dust mites.
Dehumidifier vs. humidifier: what's the difference, and which do you need?
A dehumidifier removes moisture from the air, while a humidifier adds moisture to the air.
If your room feels stuffy and you see condensation or mold, you need a dehumidifier. It's commonly used in bathrooms, basements, closets, boats, and RVs, but you can use it anywhere else in the house, too.
If your room feels dry and your skin is irritated, you need a humidifier. We tested the best humidifiers.
How does a dehumidifier work?
A dehumidifier works by blowing moist air over coolant-filled coils, causing the moisture to condense into water droplets. The condensation then drips from the coils into a receptacle.
The collected water is directly drained out or pumped into another area like a sink, depending on the unit you have.
Is a dehumidifier good for your skin?
"Dehumidifiers decrease the incidence of dry skin," said Jeanine Downie, MD, FAAD, Director of Image Dermatology PC. They also reduce irritation due to allergens like dust mites and mold.
If your dehumidifier removes too much humidity from the air, however, it may dry out your skin.
"It's important to note that if the humidity starts to drop below 30%, it can have a negative impact on health, including drying out of the eyes and mucous membranes," said McKeon. "Very dry air can also result in dry skin, worsening of eczema, and irritation of the airways." You should continue to monitor humidity levels and how your skin feels as you use your dehumidifier.
How do you clean a dehumidifier?
There are two parts to focus your attention on: the air filter and the tank. Clean the air filter under your faucet often (once a week).
Wipe down and dry out the tank after every use to reduce mold and mildew growth within your dehumidifier.