How Do Small Dehumidifiers Work?

Mini Dehumidifier

Dehumidifiers work just like refrigerators, but they extract moisture from the air instead of cooling it. They take in moist humid air and produce dry air to circulate back into the air.

The extracted water is collected in a tank that you will need to empty every so often or connect a drain hose. Small dehumidifiers do not have this drainage option, so you'll be disposing of the condensed water pouring it down the sink.

We’ll provide a detailed overview of this process in this guide.

Step by Step Guide to How Small Dehumidifiers Work

Here is a step by step description of how the best small mini dehumidifiers work.

  • An electric fan at the inlet draws in humid air. This is located at the grille at the front of the dehumidifier.
  • The warm and humid air is circulated over cold pipes. These pipes are kept cold by using a cool refrigerant flowing through them. The refrigerant is driven through a compressor. This is where dehumidifiers are like refrigerators and air conditioners in their technology.
  • When moist and warm air passes over these cold pipes, it cools down and loses its moisture content. Since the amount of moisture that air can hold is dependent on its temperature, reducing the temperature will reduce its ability to hold moisture.
  • The processed air now has a lower moisture content. However, since its temperature is low, it needs to be reheated to back to room temperature. This is achieved by passing the air over the hot condenser coils.
  • This warm and dry air is blown back into the room via another grille.
  • The moisture that was extracted from the warm humid air drips down into a container located at the bottom of the dehumidifier.

Why Water Does Not Overflow in Small Dehumidifiers

Dehumidifiers feature an automatic shutoff function which switches the device off when the water container is full. This prevents the water container from leaking.

This works by a floating plastic rising to the top of the container as it fills. Once it reaches the top, it makes contact with an electric switch which cuts power to the device.

An indicator light will then illuminate, telling you to empty the container to resume operation.

Other Types of Dehumidifier Operation

Besides the refrigeration cycle, dehumidifiers can work in other ways too. Some work through absorption or adsorption, two different methods for removing moisture from air.

Most people are familiar with absorption, but not as many know about adsorption. In the adsorption process, the water molecules in air cling onto an ‘adsorption medium’. This is simply a heated sponge which holds water.

Final Verdict

Small dehumidifiers work in the same way as larger models. Either through absorption or adsorption.

The difference is due to the type of technology used as compressor dehumidifiers and desiccant dehumidifiers dehumidify air slightly different.

Both types have their advantages and disadvantages, but smaller dehumidifiers usually use desiccant technology.

About the Author Lets Remove Mold

If you're looking to buy a new dehumidifier then you're in the right place. Through years of HVAC and mold remediation experience, the team at are able to provide advice on the type of dehumidifier you need for your home.

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