How Much Water Should a Dehumidifier Collect In a Day?

Understanding how much water a dehumidifier can manage will determine how and where you use it.

In my home, I have a large capacity dehumidifier in my basement to manage the high humidity and a smaller dehumidifier in my bedroom because it’s drier.

This works well for me, but the amount of water you need your dehumidifier to collect will depend on your humidity issues. 

So, how much water should a dehumidifier collect in a day? It can be anywhere from 1-100 pints a day, and it depends on a range of factors. 

In this guide, I’ll explain how dehumidifiers collect water and how much water different dehumidifiers will remove from the air.

How Much Water Does a Dehumidifier Collect per Day?

An average-sized dehumidifier will collect 15-20 liters of water a day if it’s used in a residential space.

Commercial dehumidifiers are generally more effective at moisture extraction and can collect up to 50 liters a day.

The actual amount of water that your dehumidifier collects in a day depends on several factors:

  • Tank capacity – how much water/water vapor can actually fit in the tank before it shuts off
  • Humidity levels – how much moisture there is to be extracted
  • The efficiency of your dehumidifier – how quickly it extracts moisture from the air. The average rate of dehumidifier collection is approximately 12 to 13 hours for a 4-liter container.

How Long Does It Take for a Dehumidifier to Fill Up?

It takes approximately 2-18 hours to fill up a dehumidifier tank.

This varies depending on the size of the tank and the capacity of the unit to pull moisture from the air.

The size of the tank is the amount of standing water the dehumidifier can hold before it needs to be emptied.

If you’re using a dehumidifier regularly then I would recommend buying a model with a large tank so you don’t have to manually empty it 2-3 times a day.

The dehumidifier capacity is how much water it can extract in a 24-hour period.

This is expressed in pints (e.g a 30-pint dehumidifier) and is usually more than the size of the tank.

Dehumidifiers have different capacity levels. The capacity refers to the amount of water that the unit can remove from the air.

The higher the capacity of the model (the greater the number of pints shown), the more excess humidity is extracted, and the quicker the dehumidifier will fill up.

For example, a dehumidifier at the 35-pint capacity that takes the room from 90% relative humidity to 40% relative humidity would take 17 minutes.

A 50-pint capacity model could do the same thing in 11 minutes.

Below is a table for how long it will take to remove the excess humidity from your home.

Remember, you may have to let your dehumidifier fill up several times over before you reach the optimal humidity levels.

Capacity Amount (Pints)90 to 40% Relative Humidity80 to 50% Relative Humidity
22 Pints34 Mins15 Mins
35 Pint17 Mins8 Mins
50 Pint11 Mins6 Mins

What Happens If Your Dehumidifier Tank Is Full?

If the tank is full then most room dehumidifiers and portable dehumidifiers will automatically turn off.

This can lead to an increase in humidity and a drop in your indoor air quality. You may also feel a rise in the ambient temperature in the room.

If you notice your dehumidifier stop collecting water, it’s a clear sign you should empty it. You’ll need to empty the tank before you can use the dehumidifier again.

I use portable dehumidifiers in my home and they work well, but I do need to empty them at least once a day.

If you need constant dehumidification, I would recommend attaching a drain line so the device doesn’t have to be manually emptied. 

How Often Should You Empty Your Dehumidifier?

Your average dehumidifier should be emptied once or twice a day.

This is enough for typical dehumidifier performance, but if you’re using a very efficient model and have a lot of humidity, then you may need to fill it up more quickly.

In summer, I typically find that I need to empty my dehumidifiers twice a day. In winter, the humidity is lower, so it’s usually every other day. 

When you first purchase your dehumidifier, make sure that you monitor how quickly the tank is filling up.

Once you know how long it takes to fill up, you can easily check on your dehumidifier and empty it accordingly.

Why Is Your Dehumidifier Filling Up So Fast?

If you notice that your dehumidifier is filling up more quickly then it could mean there’s a water leak or cracked pipe in the room causing higher relative humidity levels than usual.

Keep an eye on what your dehumidifier will usually collect in a day, and if the moisture levels increase noticeably, you should look for the source.

How Does a Dehumidifier Collect Water? (How it Works)

Dehumidifiers collect water by drawing in damp air, extracting the moisture, and then releasing the dry air back into the room.

The moisture from the air is then collected in a water tank or water reservoir.

By extracting this moisture, the dehumidifier lowers the relative humidity levels in the room and improves the indoor air quality.

The higher the humidity level, the more water your dehumidifier will collect because the longer it will need to run to lower the overall humidity level.

The efficiency of your dehumidifier can be measured by the amount of water it is able to drain over one hour.

There are two main types of dehumidifiers and the way each type of dehumidifier collects water is slightly different:

Refrigerant/Compressor Dehumidifiers

Most dehumidifiers are refrigerant dehumidifiers and I use these in my home because they remove moisture quickly.

Refrigerant/compressor dehumidifiers work by bringing in moisture through the air by sending the air through a filter and then over cold coils.

These coils lead to condensation that creates water and falls into the water tank.

Refrigerant dehumidifiers work well in most temperatures and use less energy.

They work well in locations with high humidity seasons and high moisture levels because they’re cheaper to run for longer periods.

Desiccant Dehumidifiers

The desiccant type of humidifier works by directing the air over an absorbent material.

The humidity in the surrounding air is captured on the absorbent material and dry air is released back into the room.

The absorbent material is then heated within the dehumidifier so that moisture will form.

As moisture forms, it slides down the absorbent material and falls into the water tank.

Dehumidifiers work best to maintain humidity levels in lower temperatures because they don’t have cold coils so there’s no risk of freezing.

The dehumidifier costs are higher though because they are less energy efficient.

I only use desiccant dehumidifiers in small spaces (like closets, or my car) because it can take a long time to remove the moisture from large areas.

Factors Affecting the Amount of Water the Dehumidifier Can Collect

Dehumidifiers Capacity

The dehumidifier’s capacity is basically the dehumidifier fill rate.

The capacity determines how much water the dehumidifier can create from the air as it draws moisture in.

The greater the capacity of the model, the more water the dehumidifier can bring in a day, so if you have a lot of moisture then you need a high-capacity model.

Average Humidity

The greater the level of humidity in your home and environment, the more water the dehumidifier will collect.

This is simply because you have more water to collect in your environment and areas that are lower in humidity [1] will not need to have as much water collected in order to lower the relative humidity level.

Advanced dehumidifier models have humidity settings and humidity detectors that tell you how much moisture needs to be removed.

Use this to guide when and where your dehumidifier needs to be used.

Air Temperature

The air temperature also plays a role in the amount of water collected by your dehumidifier.

At warmer temperatures, dehumidifiers tend to work better because it helps contribute to condensation.

If you live in a warmer environment, you are more likely to collect higher volumes of water each day.

This also means that you will need to empty your dehumidifier more often than someone who lives in a cooler climate.

Room Space

The amount of water collected also depends on the room space in your home.

If you are using a whole-house dehumidifier, for example, then a large amount of water will be collected.

Portable dehumidifiers are smaller, and although they work well, they cannot collect as much water or collect it as quickly.

The size of your dehumidifier will affect how much water is collected daily.


Why is my dehumidifier running but not collecting water?

If your dehumidifier is running but not collecting water, the most likely problem is with the fan motor or internal coils. The cold coils are needed to create the condensation and a fan is needed to draw air in. Make sure both your coils and fan are operating normally so the dehumidifier can reduce the humidity levels properly.

How to fix a dehumidifier that is not collecting water?

If your dehumidifier is not collecting water start by emptying the tank, unplugging the dehumidifier, and then re-plugging it back in. If it still won’t work, try to determine whether or not the interior coils are getting cold and check whether the fan is working. If you cannot identify the problem, it is time to bring in a professional or purchase a new unit.

Is water collected from a dehumidifier safe to drink?

You should never drink water from a dehumidifier. Your dehumidifier will collect clean water, however, the water sits in a tank containing bacteria, dust mites, mold, and other potential pollutants which could be harmful to your health. We definitely recommend not drinking the water from your dehumidifier.

Do you have to drain a dehumidifier?

Yes, you do have to drain a dehumidifier. Most units come with a removable tank, so you can simply remove the tank and drain the water outside or in your sink. Depending on the size of the tank and the level of humidity in your home, you may need to do this 1-2 times per day or 1-2 times per week.


How much water should a dehumidifier collect in a day?

On average, 10-20 liters but it entirely depends on the humidity levels and amount of excess moisture in the air and the capacity of the dehumidifier.

My dehumidifier tends to fill up once a day, taking about 20 liters of moisture out of the air.

This is the perfect size for me because I have protection from humidity and don’t need to empty it too frequently.

If you find that you’re emptying the tank several times a day then it may be a sign that you need a more powerful dehumidifier with a bigger tank. 



Josh Mitchell

Josh Mitchell

My name is Josh and I am obsessed with DIY and improving my family home. HVAC topics can be tricky for homeowners so I decided to share my knowledge on the subject. When I am not working on DIY projects, you can find me at the beach or my local coffee shop.