How Long Does It Take For A Dehumidifier To Work?

Jalin Coblentz
by Jalin Coblentz

Dehumidifiers are a godsend for people who live in humid or wet areas of the world. They’re excellent appliances for reducing the risk of mold, humidity, and water damage inside your home. However, they sometimes take their good old time to get the job done. Many people want quick results and are wondering how long it will take for a dehumidifier to work.

On average, a dehumidifier can take around 12 hours to work. This will depend on the size of the dehumidifier and your room’s square footage. For example, in a damp room of 500 to 1,500 square feet, use a 30-pint dehumidifier. This means you can remove up to 35 points of moisture for very damp rooms or basements in 24 hours.

Technically speaking, dehumidifiers start doing their work the second that you plug them in and turn them on. However, it will take some time before you start to see or feel the effects. If you’re thinking about purchasing a dehumidifier and have questions or concerns, you’ve come to the right place.

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How Long Does It Take for a Dehumidifier to Work?

Dehumidifiers are tasked with the job of sucking moisture out of the air and storing it in a holding container. Therefore, a dehumidifier is working from the moment that you turn it on. While you might not feel the effects immediately or even within the first several hours, rest assured that your dehumidifier is hard at work. As a general rule, the smaller your room is and the bigger the dehumidifier, the faster it will work.

In most cases, you can expect your dehumidifier to take around 12 hours to work. Most dehumidifiers have multiple settings and you can optionally speed it up or slow it down depending on your desires. If you like small amounts of humidity in the air, your dehumidifier will work faster than if you want a completely dry room.

On the top of most modern dehumidifiers, you’ll notice a series of buttons and settings. This allows you to choose the percentage of humidity that you want to eliminate from the air. You can usually choose anywhere from 50% to 80%, but the higher your setting the longer it will take for your dehumidifier to reach those levels.

Ideal Dehumidifier Size (Based on Room Size)

Dehumidifier SizeCondition of RoomSquare Footage of Room
30-pintDamp500-1500 sq ft
30-pintVery Damp500-1000 sq ft
30-pintExtremely Wet500 sq ft
50-pintDamp2000-2500 sq ft
50-pintVery Damp1500-2000 sq ft
50-pintWet1000-1500 sq ft
50-pintExtremely Wet1000 sq ft
70-pintVery Damp2500 sq ft
70-pintWet2000-2500 sq ft
70-pintVery Wet1500-2500 sq ft

Factors Affecting How Fast a Dehumidifier Works

There are a number of factors that determine how quickly and efficiently a dehumidifier will work. Everything from the room and appliance size to the setting you choose will have an impact. Let’s look at the complete list so you know what to expect.

Size of the Room

The bigger your room is, the longer it will take your dehumidifier to do its job. Rooms with more square footage and higher ceilings can take a dehumidifier anywhere between 12-24 hours to dry out. Smaller rooms with lower ceilings take 12 hours or less because of the smaller total area.

Size of the Dehumidifier

There are tons of different dehumidifiers that come in all shapes and sizes. The bigger your dehumidifier is and the larger the reservoir area, the faster it will work. Dehumidifiers with smaller reservoirs must be dumped more often because they fill up with water faster. This will slow down the drying process significantly.

The Dampness of Your Room or Home

It goes without saying, but the more damp your home is the longer it will take for a dehumidifier to work. In extreme situations such as basements without proper insulation, your dehumidifier can run non-stop until it fills up with water. Humid areas such as Florida will experience more humidity than most other parts of the U.S.

Desired Humidity Level

The dryer you want your room to be, the longer it will take your dehumidifier to work.

Height and Position of the Dehumidifier

Humidity is very light and naturally rises to the ceiling of a room. For that reason, the taller your dehumidifier is the more effective it will be at sucking moisture out of the air. Additionally, you should always try to position your dehumidifier in the center of whatever room you’re drying out. Having it in the center will make it easier to reach all parts of the room, rather than if it’s on an outside wall.

Will a Dehumidifier Work on a Whole House?

Like I said before, there are many different dehumidifier sizes to choose from. Smaller dehumidifiers won’t be able to make a dent in an entire house and are best suited for a single room. There are, however, whole-house dehumidifiers that are effective at reducing the humidity level of your entire home.

How to Tell if a Dehumidifier is Working

Just because your dehumidifier is plugged in and running doesn’t necessarily mean that it’s working. Checking the reservoir to see if there’s water inside isn’t a solid indicator either. Your dehumidifier might be doing its job, but not to the best of its ability.

The best way to verify that your dehumidifier is working efficiently is to use a hygrometer. Hygrometers are handy, cheap, little tools that measure how much moisture is in the air. You should run your dehumidifier for an hour or two and compare its reading with your hygrometers. If the two match up, your dehumidifier is working properly.

How Long Can I Leave My Dehumidifier Running?

You can leave your dehumidifier running for as long as your heart desires. Dehumidifiers are designed for heavy and long-term use and running them around the clock won’t cause any damage.

In terms of saving money, however, the best time to run your dehumidifier is from 10 p.m. to 7 a.m. This is because electricity rates usually go down at night. If you don’t want your dehumidifier to stop running, even when the reservoir fills, you can connect a drain hose to the bottom of the reservoir and make your dehumidifier think that it’s running on empty.

Related Questions

How much water can a dehumidifier consume in a day?

Depending on the size of your dehumidifier and the size of its reservoir, a dehumidifier can absorb 30 to 70 liters of water in a single day.

Are dehumidifiers expensive to operate?

Most modern dehumidifiers are designed to be efficient and eco-friendly. As a result, they’re relatively inexpensive to operate, even if you run one around the clock.

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Final Thoughts

If you struggle with humidity and moisture in your home, a dehumidifier might be exactly what you need. They’re relatively inexpensive and low maintenance to operate and very user-friendly. As long as you empty the reservoir when it fills up, your dehumidifier will run as long and work as quickly as possible.

Jalin Coblentz
Jalin Coblentz

Before I started writing, I worked for 6 plus years in the plumbing, electrical, and HVAC business. I was primarily an HVAC installer but also worked as a plumber and electrician. Now I'm a copywriter, focusing on home improvement content and guides.

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