It’s not the heat, as the adage goes, it’s the humidity.
And indoors, humidity can be a problem—particularly in basements, laundry rooms, bathrooms, and crawl spaces—any time there’s a string of warm, rainy days.
Telltale signs of too-humid air include musty odors, clammy conditions, condensation on windows, and damp spots on the walls or ceiling.
And excessive dampness can trigger allergies and even do damage to your home. “Dampness can cause mold and mildew to grow and spread on your walls and ceilings,” says John Banta, the engineer who runs CR’s tests of dehumidifiers. “And that can dampness can weaken wood.”
A dehumidifier pulls moisture from the air, collecting the water in a removable tank. But not all are up to the task.
There are currently 36 models in our dehumidifier ratings from 16 brands, and all earn an Excellent rating in our water-removal test, meaning they remove the number of pints of water from the air as claimed by the manufacturers. But our tests also found differences among the models.
A dehumidifier that earns an Excellent rating in our humidistat-accuracy tests comes close to holding the humidity level you select for your space.
And then there’s noise—most of it comes from the fan. Dehumidifiers that garner an Excellent rating in our noise tests are about as loud as a refrigerator running, while the noisiest are about as loud as a box fan set on the highest speed, earning a Fair rating.
Keep it clean. The filter cleans the air that flows through the dehumidifier, and when it’s dirty, your dehumidifier’s efficiency takes a hit. Most models in our ratings have an indicator light to tell you when it is time to clean the filter. Wash and dry it regularly, following your manual’s advice. While you’re at it, see the manual’s advice on cleaning the grill. When the grill is dirty, air movement is slowed.
Even the best dehumidifiers can’t make up for the problems that create damp air in your home.
Check gradation of the soil. It should slope away from your home’s foundation to prevent water from pooling. And don’t go crazy with the water when you’re watering plants near the foundation.