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How Do Dehumidifiers Work? Get An Adequate Answer Immediately!

Dehumidifier sucks the moisture and substances in the air like mold, fungus, etc. How can it do that? What is the operating rule? To understand more about how does it work, join us here.

Condensate dehumidifiers

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Nowadays, dehumidifiers are widely used in preserving equipment, machines, food, etc. Not only offices but also many families have chosen dehumidifiers for health and home appliances.

As you know, it’s important to keep your home environment comfortable. But if your home is a humid place, you may fail to feel comfortable. Don’t worry. A dehumidifier could help you.

So how do dehumidifiers work? What are the working principles of each type of dehumidifiers? Our articles will give you the answer below.

Types of Dehumidifiers

Dehumidifiers are now becoming more and more popular. There are two main types of dehumidifiers, and we will introduce you to both of them below..

Condensate dehumidifiers 

Condensate dehumidifiers are also called refrigerant dehumidifiers or compressors. Don’t be confused when you see different names when searching for this kind of dehumidifiers on the Internet.

Condensate dehumidifiers convert  moisture into water. This type of dehumidifier has many capacities, from 10 liters to 500 liters per day.

If you have a dehumidifier which has the 30-litre capacity, you can understand it is able to convert moisture into water at a rate of 30 liters per day.

Condensate dehumidifiers are used in both families and industries. They have reasonable prices. Great durability is another advantage of these dehumidifiers.

These dehumidifiers’ efficiency depends on the temperature and humidity level. They work most effectively at over 45 percent relative humidity, and higher if the air is cold. The higher the temperature and the humidity level are, the more effectively these dehumidifiers work.

Desiccant dehumidifiers 

Desiccant dehumidifiers don’t convert moisture into water. Hence, their capacity is not expressed in liters per hour. Its capacity is expressed in gram or kilogram per hour.

For more information about the capacity of both desiccant and condensate dehumidifiers, click here. This article will show you how to select the capacity of a dehumidifier.

Desiccant dehumidifiers are usually used in industry, pharmaceutical, electronic components, confectionery, etc. For example, in the pharmaceutical industry, excessive moisture can lead to biochemical reactions and micro-organism growth on the medicines. Dehumidifiers will keep the required humidity level for processing and storing medicines.

These dehumidifiers work efficiently at any temperature and humidity level. This  consistent performance is all thanks to the desiccant which absorbs any moisture at any temperature.

This means a desiccant dehumidifier can keep absorbing moisture even at a humidity level of 20% or lower (even below what is comfortable for the average person).

This character allows desiccant dehumidifiers to dehumidify dense materials such as plaster.

One disadvantage is that the desiccant material absorbs not only the moisture but also other odors in the air from different products such as cigarettes, cosmetics, food, etc. This is the reason why the dehumidifiers may give off a pungent odor.

How Do Dehumidifiers Work?

A dehumidifier works relatively  similar to a vacuum cleaner. It sucks in the air and extracts the moisture out. After that, the moisture will drip through a collection container, which you need to empty frequently.

A dehumidifier basically works by either way:  absorption (with desiccant models) or refrigeration (with condensate models).

The description below will give you more details on how a dehumidifier works. Be patient!

Condensate Dehumidifiers

Condensate dehumidifiers

First off, we will  show all of the important components in a condensate dehumidifier.

Let’s see the structure of these dehumidifiers:

  1. Electric fan. It uses electric power to draw in the air.
  2. Condenser
  3. Capillary tube
  4. Evaporator
  5. Condensate tank: It is a removable reservoir; You will have to pour   out the water. But don’t worry too much about overflowing — most dehumidifiers have an automatic shut-off.
  6. Refrigerant
  7. Compressor

These dehumidifiers are constructed on the same principle of cooling and condensing water as that of air- conditioners. These dehumidifiers operate dehumidifying moisture in the air and  by passing it through a cooling system to condense into water.

While the air-conditioners blow out cold air, this type of dehumidifier draws the air into the unit. The airflow carrying steam runs through the filter and the model will condense moisture into water. The remaining air will be released out of the machine while the condensed water will go down to the tray.

Desiccant Dehumidifiers

Desiccant dehumidifiers

Now, how about the structure of a desiccant dehumidifier? It looks much more simple, right?

  1. The desiccant. It is simply a substance that absorbs moisture. Especially, the desiccant can give out the same absorbed moisture when made warmer, which is the key to the  function of this dehumidifier.
  2. A rotor. This drum is as large as the unit itself. The rotor has layers of flat sheets that are full of the desiccant. This desiccant drum will take moisture away from the incoming air.
  3. A condenser. This component condenses warm damp air.
  4. A heater. This part helps in reheating the air.
  5. Blowers.

The rotor, the most important part of this dehumidifier, is at the center of the model. It has two different parts – a “process zone” and a “recharge zone”.

First, the moist air will be pulled through the condenser and then through the first zone. After that, it will be absorbed into the desiccant. The air going through the process zone will immediately go out of the dehumidifier.

There is a heater covering the recharge zone. This heater is responsible for warming circulated moist air which is made to move back by the rotor. The air, after becoming warmer, liberates dampness from the desiccant.

Therefore, moisture will be expelled from the desiccant. The warm moist air leaving the recharge area will enter the condenser of the dehumidifier. It then condenses at average temperature.

The condensate drops into a tank similarly to the way it does in a condensate dehumidifier.

This video will show you more clearly about how a desiccant dehumidifier works.

How Do You Know If A Dehumidifier Is Working?

As you see, a dehumidifier includes many components. Thus, it seems to be difficult for you to check if there are any problems.

Our instruction will show you the way how to tell if your dehumidifier is working properly.

A hygrometer

You can use a hygrometer to monitor the level of humidity and check if your dehumidifier is working properly. You can place  a handy and battery-powered hygrometer on the place or hang it on the wall.

If the level of humidity remains ideal, your dehumidifier is collecting water. Congratulations! In other cases, the  hygrometer will help you realize that your unit is not in good condition.

If you don’t have much knowledge about electrical appliances, we hope that these few things below can help you out. Check to find out if your dehumidifier have any issues.

Some typical problems

1 . No/low water level 

If your dehumidifier works irregularly and the level of humidity doesn’t change as expected, you may need to set the humidity control to a drier mode.

When it operates without filling the tank, the refrigeration part might have problems. In these cases, try making the exterior and filter clean. If it does not work, it is time to call a mechanic for help.

2. Full water tank

If the indicator light is on, but your device doesn’t operate, check the level of water in the tank

Basically, when the water bucket gets full, a switch should turn off the unit. If this part isn’t full of water, the switch might be activated by chance.

In this case, you have to push the switch or adjust the bucket.

3. No air comes out when it’s working

The fan motor may be burned out and you need to replace it. Remember to clean the fan regularly to lengthen its lifespan.

4.  Frosted coils

The condensation may freeze, which can result in frosted coils of the evaporator. In the winter, if your dehumidifier doesn’t continue working, keep in mind to check the coils.

How To Make Your Dehumidifier Works Properly All The Time? 

To ensure that your dehumidifier works properly all the time, here are some tips for you:

  1. Read the instruction carefully to get useful tips  from the manufacturer.
  2. It is very important to set the humidistat of your dehumidifier at around 35% relative humidity.If the humidistat is set at an extremely low humidity level, your dehumidifier will run continuously. We are sure that you don’t want to waste energy and have to pay higher electric bills.In many households, a certain humidity level is required to avoid drying out the paint or control static electricity.Excessive dryness may even cause some health problems such as chapped skin and lips, bloody noses, etc.
  3. Remember to clean the water container to prevent mold growth. Do it every month or as often as required. Don’t forget to power off and  unplug your dehumidifier before cleanup.Take out the water container then wash it with a small amount of detergent and warm water. Dry it thoroughly before putting it back to your dehumidifier.
  4. Clean or replace the air filter once a year. You need to check it twice a year for tears. If there is any damage, fix it immediately. Again, check the owner’s instruction for more information.


After all, we hope this article has given you a concise overview of two main dehumidifier types and their working principles.

Remember each type of dehumidifier has its own advantages and disadvantages. Consider all their features (capacity, size, working principles, etc.) and your need before buying a dehumidifier.

We hope that this article will be helpful to you. Please feel free to comment and let us know your opinion. Thank you for reading!

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