How Long Does It Take For a Dehumidifier to Work

How Long Does It Take For a Dehumidifier to Work: FAQs and Complete Answers

Too dry air as well as excessive humidity in the room negatively affect your health and the condition of objects in the house and their service life.

Therefore, most install a dehumidifier that helps to decrease the humidity level. (Not to be confused with a humidifier which, on the contrary, helps to increase humidity levels in arid regions).

After purchasing a dehumidifier, the owner has several questions.

How do I know if my dehumidifier is working?

How long does it take for a dehumidifier to work?

How long should I leave a dehumidifier on?

These questions and many others interest everyone who uses a dehumidifier for the first time. So, read the article and find answers to all your questions.

how long does it take for a dehumidifier to work
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The most popular types of dehumidifiers for home purposes

Residential dehumidifiers. This is an excellent option for smaller rooms as it does the work fast and efficiently. But it isn’t suitable for larger rooms as it can’t control more moisture expected to be collected during large room drying.

Portable dehumidifiers. This device is great for a single room, for example.

After drying one room, you can move it to another room or a completely different room.

Portability is the main advantage of this dehumidifier. But there is also a drawback: the tank fills up with water very quickly, so it is necessary to constantly monitor and empty it in time.

How long does it take for a dehumidifier to work?

Most dehumidifiers start working immediately after switching on and require up to 12 hours to do the job and to bring the ideal humidity level.

More powerful dehumidifiers can decrease the humidity level from 90% down to 40% almost in no time.

20-30 minutes is enough to dehumidify the room of about 50 square feet. However, some dehumidifiers need 12 hours or more to cope with the task.

The duration of the dehumidifier work also depends on the following factors: dehumidifier capacity, the dampness level of the room, room size, and the temperature and climate of the region.

How Long Does It Take For a Dehumidifier to Work
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Dehumidifier capacity

The capacity of the dehumidifier means its ability to extract excess moisture from the same size area and then remove moisture. In other words, capacity is how much humidity is extracted for 24 hours by a dehumidifier.

Most dehumidifiers have built-in water tanks.

The minimum required capacity of the dehumidifier’s water tank is 25 pints. The most commonly used capacities of those tanks are 50- and 75-pints.

It is very important to define the right dehumidifier capacity for your room as a high-capacity dehumidifier can extract more water from the same surface area and in the same amount of time than a dehumidifier with a lower capacity.

Thus, a high-capacity dehumidifier will cope with the work faster and reduce energy costs.

How Long Does It Take For a Dehumidifier to Work
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The room’s dampness level

The humidity level of the room is also an important factor that should be considered when choosing a dehumidifier. How to define it?

If you notice the appearance of unpleasant odors, mold growth, etc., then most likely the relative humidity of the air in your home exceeds the norm.

You can also purchase a hygrometer to check for high humidity levels.

The acceptable level of humidity in living rooms varies from 30-45% during cold periods and 60% for the rest of the rooms such as a basement or crawl space.

In warm periods, the permissible level of humidity for the living room is 30-60% and no more than 65% for other rooms.

hygrometer to check for high humidity levels
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Room size

The size of the room to be dehumidified is also of great importance. It takes from a few minutes to a few hours to dry small rooms.

For a large room, it takes much longer, from a few days to a week of dehumidifier work.

In this case, you should be ready to constantly monitor the device, as well as measure the relative humidity of the air until you are satisfied with the result.

How Long Does It Take For a Dehumidifier to Work
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The temperature in the room and the environment is another factor to consider.

You should know one fact: temperature decreasing brings relative humidity increasing even without changing the amount of water in the air.

For example, if you take an 80°F room with 40% humidity and lower it to 60°F without removing any water, the humidity becomes 48%.

So, with the onset of cold weather, moreover, if you live in humid regions, you simply cannot do without a dehumidifier.

How Long Does It Take For a Dehumidifier to Work
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How do I know if my dehumidifier is working?

To make sure that the dehumidifier is working, you just need to check the readings of the hygrometer.

Take measurements before starting the dehumidifier running and then about an hour later.

If the humidity levels have decreased, the device is working. Leave the dehumidifier run and check periodically until the desired result.

You can also check the presence of water in a special water tank or the drain hose.

If you see water, this also indicates that the dehumidifier is working.

How long should you leave a dehumidifier on?

How long does it take for a dehumidifier to work? Or, How long it is possible to leave a dehumidifier on?

It all depends on the type of dehumidifier.

If your device has intelligent humidity control, then you don’t need to do anything.

A modern dehumidifier will do everything for you: determines the level of moisture and turns on and off as needed.

With dehumidifiers without self-control, you’ll have to periodically look at the hygrometer readings and turn off the device manually as soon as you reach the appropriate readings.


What is a dehumidifier and how it works?

The dehumidifier was invented to reduce the humidity level in the room and keep it at a relatively constant level.

It is especially important to have a dehumidifier for those who live in humid regions.

This device will help to reduce moisture levels, and as a result, eliminate musty odors, and prevent the growth of fungus and mold, and the appearance of dust mites.

Modern dehumidifiers guarantee not only comfortable thermal conditions for life but also the elimination of factors harmful to health.

Dehumidifier work principles resemble the work of an air conditioner.
Dehumidifiers extract moisture from the air that passes through the dehumidifier unit.

Depending on the type of dehumidifier, the extracted water either turns into condensate during the refrigeration cycle in condensate dehumidifiers or is absorbed by hydrophilic materials in absorption dehumidifiers.

How long does a dehumidifier take to dry out a room?

If we talk about a small room, then the dehumidifier will need a few hours to remove excess moisture and improve air quality.

One large room will take longer to dry and decrease moisture levels, from 12 hours to the entire day.

And to dry an entire house or other large space, the dehumidifier running probably will last for several days.

How long does it take for a dehumidifier to collect water?

On average, the dehumidifying process lasts for 10-12 hours and the same time is required for the tank to be filled.

But if the humidity levels of the room are too high, the process lasts longer and that means the dehumidifier fill happens more often and you have to empty the tank a couple of times.

Larger rooms require more time to dehumidify and more time for emptying the tank.

A whole house dehumidifying process takes even a few days.

So, watch after the water tank carefully to empty it in time.

You can also install the drain hose for a constant drain option not to worry about the filled tank and not to empty it if you have no possibility.

Do the dehumidifiers lose effectiveness over time?

A dehumidifier cannot work forever. 5-10 years is the average indicator of work duration. But with proper care and operation, the dehumidifier can serve longer.

Clean the cold coils and exhaust grills regularly.

Don’t forget to check the air filter and water tank. If you cannot do it yourself, contact the nearest service center.

How does water appear in the dehumidifier?

The dehumidifiers work cycle consists of absorbing warm air from the surrounding space. Then the air passes through cold coils where the water vapor is turned into liquid water.

The liquid water is collected in a tank or extracted through a hose.
On average, a dehumidifier can collect from 10 pints to 100 pints of water in a day depending on the dehumidifier’s capacity and the air humidity of the space.

You’d also know that dehumidifier water isn’t useful and you can’t drink it.

This is technical water, which is suitable only for everyday purposes such as cleaning, watering plants, etc.

Final thoughts

Now, you know how long does it take for a dehumidifier to work as well as other features of a dehumidifier run.

Also, now you have a general image of what humidity levels should be ideally, how does the dehumidifier run and where does the dehumidifier collect or trap moisture, how much moisture can a tank collect, and other important information about dehumidifiers and their dampness level capacity.

In addition, among a great variety of dehumidifiers, you can choose those exceptionally suitable for your purposes.

Note: If you actively use your dehumidifier, take care of having no pipe leaks.

Don’t leave your windows open too. These factors can influence the moisture level and make the device work constantly increasing your energy costs.

Read Also: Why Does Dehumidifier Blow Hot Air

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