Get the Most From Your Dehumidifier

Even a great dehumidifier can deliver lackluster performance if used incorrectly. Follow these tips to keep yours working at its best.

Select the right size. Before buying a dehumidifier, figure out which size best fits your space. Our article “What Size Dehumidifier Do You Need?” offers step-by-step instructions and a neat dehumidifier size chart. CR readers with All Access membership can also view our full ratings of small-capacity, medium-capacity, and large-capacity dehumidifiers. 

Set the right humidity level. Indoors, the optimal relative humidity level is below 50 percent. If the humidity is higher than that, it can breed dust mites, mildew, and mold, which can trigger allergies and cause other health problems.

Pick the right spot. Placement is key. Be sure to allow enough room for air to freely flow into and out of the dehumidifier. Most of the models in our ratings release air through vents on the top, but a few vent out the side. So leave some space around your dehumidifier so that the vents aren’t obstructed, keeping the unit at least a foot away from walls and furniture.

Close all windows and doors. Enclosing your space will help keep humid air from entering your home, allowing your dehumidifier to work more efficiently.

Empty the tank regularly. All of the dehumidifiers in CR’s tests have an indicator that lights up when the tank is full, and the unit shuts off automatically. You can either empty the tank yourself or connect a hose to divert the water to a drain nearby. Some dehumidifiers, conveniently, have a built-in pump that pushes water up and out through the hose and into a sink or even outside (through a basement window, for example).

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. Many models in our ratings have an indicator light to tell you when it’s time to clean the filter. Wash and dry the filter regularly according to your manual’s advice. While you’re at it, read the manual’s guidelines on cleaning the grille. When the grille is dirty, air movement is slowed. CR also recommends doing a deep cleaning and sanitizing of the tank at least once a week.