How a Dehumidifier Works

If you understand how a dehumidifier works, you’ll be better able to choose the best dehumidifier for your needs. The whole process is not as complex as you might imagine. So how does a dehumidifier work?

How it Works

A dehumidifier works a lot like an air conditioner. There is a fan that pulls in air from the room. The air blows across the evaporator coils, which are cold. That causes the water in the air to condense on the cold coils. It’s just like water will condense on the sides of a cold glass of iced tea on a hot summer afternoon.

Then the water that has condensed on the coils drips into a collection bucket. Most dehumidifiers have sensors that alert you when the bucket is nearly full. Then you must remove the bucket, empty it and replace it. Most dehumidifiers will shut off automatically if the bucket gets full to prevent it from overflowing.

How often you need to empty the water bucket depends on how humid the air is in the room you wish to dehumidify. If you have a good dehumidifier in a very humid room, you may need to empty the bucket every couple days. If the room is not so humid, you’ll need to empty the bucket less often. Make sure to wash the bucket out periodically because bacteria can grow in stagnant water.

Some dehumidifiers allow you to attach a hose so that water can drain continuously. Then you don’t have to bother with emptying the water bucket.

Meanwhile, the fan then blows the air past the compressor coils, which are warm. The warmed, dry air is then blown back into the room. Because the air that comes out of the dehumidifier has been warmed, the room temperature may seem a bit warmer, especially close to the dehumidifier.

Some dehumidifiers, such as Frigidaire brand dehumidifiers, have a special filter that the air passes through before it returns to the room. The filter removes allergens and bacteria from the air. That’s an important factor in how a dehumidifier works because it greatly improves the air quality in a room.

How Does a Dehumidifier Work to Control the Level of Humidity in a Room?

Now you know how a dehumidifier works to remove moisture from the air. Many dehumidifiers allow you to select exactly how much humidity you want in a room and they remove just enough moisture from the air to maintain that level of humidity. But how does a dehumidifier work to maintain the desired amount of humidity in a room?

These dehumidifiers contain a part called a humidistat. The humidistat contains a sensor that determines how much relative humidity is in the air. The dehumidifier automatically turns off when enough moisture has been drawn from the air to reach the level of humidity you selected. When moisture begins to build in the air again, the dehumidifier automatically turns back on.

How Does a Dehumidifier Work to Prevent Mold?

People purchase dehumidifiers for many reasons, but a common reason these days is to prevent mold in the home. Mold in the home can lead to all sorts of health problems, including respiratory problems. Excessive moisture is a significant contributing factor to mold growth. So how does a dehumidifier work to prevent mold? By simply keeping the humidity in your home at 50 percent or less, mold will find it difficult to grow and spread.

If You Want to Learn More

Follow this link for more information about what size dehumidifier is right for your needs. To learn about which brand of dehumidifier is best, just follow this link to our Dehumidifier Reviews page.

Return From How A Dehumidifier Works To Our Dehumidifier Ratings Page

Black Mold Health Symptoms Home Page

Do You Need a Hygrometer?

Dealing With Mold

Testing for Mold

Cleaning Mold