A dehumidifier removes excess moisture from the air. It sucks in the moist air, condenses the moisture into the water, and collects it in the bucket. It then releases the dry air back into the room.

In another article, we looked at how humidifiers work. They inject some moisture into the air in your home.

To have optimum humidity, sometimes you may have to lower the moisture in your indoor space. Sometimes, you may have to raise it. It depends on the circumstances.

Mostly, we use dehumidifiers in summer when there is too much humidity. We use humidifiers in the winter when we turn on the heating systems. They suck all the moisture from the air.

As you can therefore see, the best thing is to have both the humidifier and the dehumidifier at home.

Back to the dehumidifier now… How does a dehumidifier work? And how does it remove the moisture from the surroundings until you have just the right level of humidity?

How does the moisture that it collects turn into liquid water?

Well, those are questions to ponder, especially when the appliance works so well to give you clean air, free from excess moisture.

Really, how does a dehumidifier work?

how does a dehumidifier work

A dehumidifier removes excess moisture from the surroundings so that mold, mildew, dust mites, and other allergy-causing organisms do not thrive. It helps to prevent too much humidity inside your home.

What you end up with is air with the required level of humidity that prevents the growth of mildew, stuffiness, and musty odors.

To understand how dehumidifiers work, you need to know about the different types. Each type of dehumidifier functions differently.

Types of dehumidifiers and how they work

There are many types of dehumidifiers, but they are not all equal. Just as we have different types of humidifiers, so do we have different types of dehumidifiers.

There are two main types of dehumidifiers: refrigerant dehumidifiers and desiccant dehumidifiers.

1. Refrigerant dehumidifier

The refrigerator-style dehumidifier is the most common. It works on the same principle as the fridge.

This dehumidifier has a fan that draws moist air from its surroundings to the dehumidifier. The moist air passes over the dehumidifier coils containing refrigerant, where the moisture condenses and is collected in the water containers.

The cool metal plate collects moisture the same way that moisture forms on the outside of the cold glass on a hot day.

The air is then released back into its surroundings.

These dehumidifiers work best at room temperature. However, they do not function well in cold conditions, mainly because the cool metal plates are already covered in ice. The freezing can occur at a temperature of 65°F (18°C) or below.

If you desire to use a refrigerant dehumidifier at low temperatures, then you need to make sure it has additional features such as auto-defrosting capabilities and components with higher performance.

Alternatively, you can use a desiccant dehumidifier.

2. Desiccant dehumidifier

A desiccant dehumidifier uses a desiccant to absorb moisture from the air. A good example of a desiccant is the ‘silica gel’ usually packaged with shoes, computers, and other products, whose purpose is to absorb moisture.

The desiccant in the dehumidifier absorbs moisture in the air.

The humidifier has a wheel that is mainly made of desiccant. As the air comes into the humidifier, the wheel turns slowly as it absorbs the moisture.

As it rotates, part of the wheel passes through warm air, which removes the moisture from the desiccant. The condensed air is then collected in a tank.

Desiccant humidifiers are suitable for use at low temperatures where the refrigerant type is not suitable. You can use them in cold places, such as the garage, or during the winter.

Unlike the refrigerant kind of humidifier that needs to cool the air before dehumidifying it, desiccant dehumidifiers do not need to do so. This is what makes desiccants most suitable for use in cold areas.

Although they are smaller and lighter, one of the disadvantages of this type of dehumidifier is its high consumption of power.

Benefits of using a dehumidifier

Benefits of using a dehumidifier

Alright. How does a dehumidifier work? Now you know. We have already explained it in detail. Now, you may be wondering whether you need one. Yes, you do!

Here are a few reasons why you need one:

Dehumidifiers give relief for respiratory problems

People suffering from asthma and other respiratory diseases find it difficult to breathe in humid conditions.

OK, we did write about some of the good humidifiers for asthma. A little moisture in the air is not bad at all. However, when it is too much, it can hamper your breathing.

If you suspect that your home or office is humid, then you need to invest in a Danby dehumidifier or any other.

Red flags of excess humidity include peeling walls and the presence of the notorious indoor allergens of dust mites and mold.

You may also experience reactions such as difficulty breathing, watery eyes, a stuffy nose, wheezing, and sneezing. The allergy triggers present in humid conditions cause all of these problems.

How does a dehumidifier work? No more odors

A humid home usually has a musty smell because of the mold. You may experience this smell on your walls, clothing, and in the general air in the basement. A dehumidifier helps to reduce these odors.

Protects your belongings from damage

Mold can develop on food, furniture, and clothing, and it can lead to corrosion or rust on electronics. If you are not careful, you could suffer hefty losses from having too much humidity inside your home.

A dehumidifier removes the moisture that causes mold, so your belongings are safer from mold-related damage.

Tips when buying a dehumidifier

You need to be careful when buying a dehumidifier. There are so many of them on the market. Some are small, and some are big. However, not just any model will be suitable for you.

Here are a few tips that can guide you in making the right choice of dehumidifier.

Assess your needs

You need to buy a useful dehumidifier. If it is too small, it might not help you in a big room. If it is too big, it might make the air in a small air too dry.

Some of the questions you should ask are:

  • What is the temperature of the area that needs dehumidifying?
  • How large is the space?
  • How much do I want to spend?

Remember that in cold areas, the desiccant dehumidifier performs better than a refrigerant.

Choose a dehumidifier that is suitable for your space. While small and portable dehumidifiers can serve a small space comfortably, you will need to buy a large dehumidifier for larger spaces.

If you want to dehumidify your whole house, then you can opt for a whole-house dehumidifier. Unlike portable ones that are so easy to use, a professional installs the whole-house dehumidifier.

It is easier to install if you have existing ductwork for your heating or central air unit. They are also more expensive, and they are only suitable if you are dealing with a serious case of moisture in your home.

The easier approach is to get several portable dehumidifiers for different rooms in your home.

Choose your desired dehumidifier features

Dehumidifiers have different features. Usually, the more features an appliance comes with, the higher the cost. In your search for information about how a dehumidifier works, you want to consider its features. They are everything!

Some of the features to consider include an internal pump, automatic start, silent mode, and customized humidity levels.

Internal pump: How does a dehumidifier work?

For instance, you can opt for a dehumidifier with an internal pump if you do not want to keep checking the drainage or emptying the tank. Alternatively, buy one with a larger tub to accommodate more water.

Automatic on/off feature

You don’t want to keep turning the dehumidifier on and off. Then go for the one that has an automatic start. You just need to set it at a particular level at which it either starts or goes off, depending on the level of moisture in the house.

Some models have an automatic shutoff that switches off the unit when the tank is full. Check this article that I did on dehumidifier symbols and their meaning.

Silence or noise level of a dehumidifier

You don’t want a noisy dehumidifier? You are in luck since there are silent models. They make what we call “white noise,” which is very friendly.

To save on the cost of maintenance, opt for a dehumidifier with a reusable air filter.

Humidity controls/settings

To get a specific level of humidity, choose a unit that has humidity controls. All you need to do is select the desired level of humidity, and the appliance will maintain it.

Alternatively, you can get a hygrometer so you can know when to turn off the machine. In the summer, humidity should be between 40 and 50 percent, and in the winter, is 30 to 50 percent.


How does a dehumidifier work? This should no longer bother you since we have answered it here. In conclusion, a dehumidifier works by sucking in the damp air, condensing the moisture in it, and storing it in a tank, and then it releases the drier air back into the room.