How Long Can You Leave a Dehumidifier Running?

How long do I keep my dehumidifier on for?

This is a very common question. People ask it when they buy a dehumidifier for the first time. Others ask if they have an old unit that does not have a humidistat.

This is the same as asking: How long does it take to dehumidify a room?

Well, no one wants to buy a dehumidifier or a humidifier blindly without knowing how fast it can work.

When summer sets in, it is time to crank up the whole house dehumidifier to get rid of the excess moisture.

If you don’t, it could damage your furniture, paintings, walls, and clothing, and it could cause a mold infestation.

So how long do I keep my dehumidifier on? 6 to 7 hours of running a dehumidifier should get rid of the excess moisture in your indoor air. When it is new, it can take more than 10 hours to start working. However, if it is not new, running a portable dehumidifier for 20 to 25 minutes should be enough to lower the humidity in a 50-square-foot area.

Use a hygrometer to remove all doubt

How long do I keep my dehumidifier on for

The reason for running a dehumidifier is to lower the humidity level to between 30 and 50%. If you let the humidity level rise too high, it can cause serious mold sickness symptoms.

The best option is to run a dehumidifying unit to lower the moisture content in the air. But you should not run it blindly!

It is vital to know how long to run your dehumidifier, lest you remove all humidity from the air.

You could buy one with a humidistat so that it switches off when relative or the set humidity is attained. However, if that is not possible, there is another way.

Just buy a hygrometer! This device keeps tabs on the humidity level in your indoor space. You can get a wall hygrometer that runs on a battery. Check it frequently to know when you need to lower the humidity level in your house.

If possible, get a hygrometer that comes with a thermometer. Temperature is related to humidity. Warm air holds more moisture content!

Thus, if you notice more warmth inside, chances are high that the humidity will rise too, especially if it is summer.

Buy the right size unit

How Long Can You Leave A Dehumidifier Running

When you have a hygrometer to show you the humidity levels in the house, run the dehumidifier for as long as necessary.

The duration will depend on many things. However, the most important one is the size of the unit. If you are using a small unit in a big room, you might have to leave it on longer. It will take more time to lower the relative humidity level.

It is vital to look at the space rating before you can order a unit. If the manufacturer says it is suitable for 250 square feet, do not use it for 450 square feet. It will simply take too long to lower the RH level in that kind of space.

Frequently Asked Questions for Dehumidifiers

When finding out how dehumidifiers work, you want to know how fast they can remove excess humidity from the air.

To clear the air some more, we have anticipated and answered the questions that most people ask. These include things such as:

  • When is the best time to run a dehumidifier?
  • How long does a dehumidifier last?
  • How long does it take for a dehumidifier to work?
  • How long should a dehumidifier last?
  • Can I leave a dehumidifier on all day?
  • How long should I run a dehumidifier after a flood?
  • Is it safe to leave a dehumidifier on all night?
  • How much electricity does a dehumidifier use?

We will only answer the most outstanding questions and later do a full FAQ for dehumidifiers.

Read more helpful articles:

How to stop humidifier white dust

When to use a humidifier for your plants

Indications of high humidity in a home

Here they are:

How quickly should a dehumidifier fill up?

You should keep your dehumidifier on for as long as it takes to fill up. However, bigger, 70-pint humidifiers such as the Frigidaire can be fixed with drainpipes so that you don’t have to worry about emptying them.

Such are best suited to removing excess humidity from areas that are larger than 1000 square feet.

If you have bought a new dehumidifier, it could take more than 10 hours to fill up. However, if it is not new, a portable dehumidifier such as this can take up to 7 hours to fill up.

How long it takes to dehumidify a room depends on the size of the room and the capacity of the dehumidifier.

For example, a 22-pint dehumidifier will take 17 minutes to lower humidity from 80% to 50%. Of course, this is just a guideline, so it can probably take longer or shorter than that.

A 35-pint unit can take 9 minutes or thereabouts to lower the relative humidity to 50% from 80%.

A 50-pint one can take 7 minutes to lower humidity from 80% to 50%. Therefore, as you can see here, the higher the capacity of your unit, the faster it can dehumidify a room.

How often should I use a dehumidifier?

Should a dehumidifier run all the time? The answer is no, it should not. The good thing is that a dehumidifier can switch itself off once the set humidity level in the room where you are using it is attained.

How often you can use this appliance depends on how humid your home is. For example, humidity is high in southern Florida throughout the year.

Therefore, a person living there is bound to use a dehumidifier more than a person who lives in a dryer place, such as Utah.

Image of how long should a dehumidifier last
A portable dehumidifier

You can use a hygrometer to find out the humidity level in your home. If the humidity level is above 50%, you should run your dehumidifying unit.

If the set humidity threshold is not met, it can turn itself on automatically if it has an auto-off/on feature, even when you are not at home.

How many dehumidifiers do I need?

If you do not have a whole-house dehumidifier, chances are you will need a portable dehumidifier for every room, especially if you live in a large country house.

OK, alongside this question, many people also ask: Can a dehumidifier dehumidify more than one room at the same time?

If you live in a small townhouse apartment, you can open all the doors to the rooms so that your dehumidifier can work on the air in all of them.

How long should you run a dehumidifier after a flood?

With the weather playing havoc all the time thanks to the global warming phenomenon, when a flood strikes, it hits hard. So how long do you keep yours on after a flood?

Well, this depends on the severity of the flood. If it was quite intense, we can say you can keep the unit on for as long as need be, until the walls are completely dry. This can take several weeks altogether!

If the flooding was not too intense, you can run the unit for a few days. Keep running the dehumidifier 24/7. If the humidity goes below 50%, it will turn off automatically, and vice versa.

How long should a dehumidifier run per day?

Should a dehumidifier run constantly, or are there specific times when you should switch it off? If it is a new appliance, you can run it for 12 hours a day.

A new unit takes a longer time to start drawing the excess moisture from your indoor air. If it is an old dehumidifier, run it for 6 hours or 7.

When should I turn off my dehumidifier? Do that as soon as the hygrometer shows you that the humidity level is 50%.

Also, if you notice that the humidity level has not been going down despite running the appliance for hours, you need to turn it off and check whether it is faulty.

It is not a good idea to keep your unit running all the time because it can draw all the moisture from your indoor air.

This can affect your indoor plants. It can also make you run a humidifier to raise the indoor humidity level.

How long do dehumidifiers last?

3 to 10 years is a good lifespan for your dehumidifying unit.

Even if it keeps running throughout the day, it should last for at least 5 years. Of course, these will not be maintenance-free years.

You need to keep the dehumidifier coils clean all the time. Change the filters when the need arises, and generally keep the appliance clean.

Of course, if you live in a very humid area where this workhorse has to work heavily, it could live a shorter life, but it will be worth it.

If your unit runs all day, it needs more regular care and maintenance. If you crank her up a few times a day, you need not clean it every week. Find a schedule that works for you!

Does running a dehumidifier use a lot of electricity?

Does a dehumidifier use a lot of electricity? You will ask this question, especially if you have to run it 24/7.

We won’t mince words. We should tell you straight away that this appliance is going to increase your electric bill.

Before you buy a unit, check the energy consumption. It should be indicated somewhere by kilowatt-hour.

Basically, to make this easier, we can say that the electricity cost of a dehumidifier should not be more than $200 per year.

Wrapping it up

If there has been flooding, running a dehumidifier non-stop is your best bet until the indoor humidity is restored to 50%.

Regarding whether it is safe to leave it on all day or all night, this depends on the level of humidity that you have in your home.

So, run it for as long as necessary. If it has a humidistat, it will turn on and off automatically depending on the humidity level.

Remember, humidity control and indoor temperature go hand in hand.

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