How Do Dehumidifiers Work?

How Do Dehumidifiers Work?

Dehumidifiers reduce humidity in the home and make the air around you lighter and fresher. Too much humidity can be super uncomfortable. This is especially true on a rainy or foggy day or when the weather is hot. Humidity makes the air muggy and heavy and can make for a bad hair day too. But excess moisture can also be bad news for you and your home. If there’s too much humidity, it can allow mold and mildew to grow in your home. This can make indoor air unhealthy to breathe. Thankfully, there’s a solution to make things less sticky when you’re indoors: a dehumidifier. But how do dehumidifiers work?

The opposite of a humidifier, which adds moisture to the air, a dehumidifier removes moisture from the air. The result is a more comfortable environment in your home. If you live in a tropical zone or near the equator or a coastal region, you’re probably more familiar with the effects of humidity than you’d like to be. A dehumidifier could be just the reprieve you need to help improve the overall air quality of your home.

So how do dehumidifiers work exactly?

The relative humidity of your home should run between 30% and 50%. If it’s any higher than that, a dehumidifier can help get it where it needs to be. A dehumidifier has four basic parts that work together to remove excess moisture: a fan compressor, cooling coils, reheater, and a reservoir. Here’s how it works:

  • First, the fan draws air from the room into the compressor, rotating it in a counter-clockwise fashion. Have you ever had an old school ceiling fan? If so, you might remember that there was a switch on the fan that changed the direction of the fan blades. Instead of pushing the air down to cool you off, it would move the air up towards the ceiling. The dehumidifier does the same thing by pulling air into the unit. The fan pulls the air towards it to collect hot moisture from the environment.
  • Next, after the unit sucks in air, the air passes over the cooling coils. The warm air turns into moisture as it cools quickly. The hot, humid air that swirls over the cooling coils turns to water.
  • The moisture gathered by the hot air collects in the reservoir of the dehumidifier. The reservoir is often a bucket within the machine that needs to be drained frequently. Some devices even have a place for a hose to connect to dispose of the leftover reservoir water.
  • Finally, the cold air is reheated and pushed back out into the environment without the moisture. The reheated air isn’t hot like a furnace would produce. The system warms the cold air back to room temperature before releasing it back out.

The best dehumidifiers have a humidistat, which enables you to set the level of humidity that you want. The humidistat has a sensing element that detects changes in the amount of relative humidity. When the dehumidifier produces the desired humidity, it automatically turns off. When the humidity goes out of range again, the dehumidifier turns back on. Technology is a wonderful thing, isn’t it?

Tips to helping your dehumidifier work better

A few steps can improve the performance of your dehumidifier. If your unit works less efficiently, your home can build up yucky mold or mildew. These easy tips can keep your dehumidifier working its best.

Close all doors and windows in the room where your dehumidifier is located. It will prevent it from running all the time, which could shorten the lifespan of your appliance.

Place the dehumidifier in an open area. Air will circulate more efficiently through it. Avoid putting it against a wall where it will have to work harder. Make sure there’s at least 12” of space around your dehumidifier’s air vents. 

Replace the dehumidifier’s filter, or clean it regularly. This will prevent mold, mildew, or dust from accumulating on the filter, which could decrease your dehumidifier’s efficiency. Follow the manufacturer’s guidelines on maintaining the filter.

Clean the coils of the dehumidifier once a year or so. Air passes through these coils and may contain fungal spores and dust. It’s a good idea to turn off the dehumidifier and unplug it first. Use a vacuum hose to remove dust or mist the coils using water in a spray bottle. Then, wipe down the coils with a soft cloth.

Look for frost in the coils when the weather turns colder. When the temperature is below 65°F, ice can build on the coils, reducing the dehumidifier’s efficiency. If you see frost, turn the dehumidifier off and unplug it from the wall. Wait for the ice crystals to melt before using the appliance again. You may also want to check the manufacturer’s guidelines to see if you should run your dehumidifier in winter.

Clean the reservoir of your dehumidifier regularly. Mold can collect in the container, or the water can become stale. That wouldn’t be the best thing for your health.

When turning your dehumidifier off for maintenance, allow ten minutes before turning it back on. It helps to level off the pressure and will extend the life of your dehumidifier.

Ready to invest in a dehumidifier?

Now that you understand the answer to “How do dehumidifiers work?”, you can see how useful they are. Dehumidifiers reduce humidity in the home by removing excess moisture, thereby increasing your living space’s comfort. A dehumidifier can help to control humidity in areas that are prone to mold growth. Without abundant moisture in the air, mold spores cannot multiply as quickly. 

Dehumidifiers make your indoor environment healthier and more breathable. (Believe it or not, dehumidifiers can even kill fleas!) If you’re ready to buy one for your home, check out our Best Dehumidifier Reviews to find one that suits your needs. Regardless of which one you buy, putting the appliance in a spot with good circulation and performing regular maintenance will extend your unit’s life and help it work efficiently.

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