Everything You Need To Know About Dehumidifiers (For Beginners)

Edge Equipment Hire provide high quality dehumidifiers that are available for hire that are suitable for a variety of applications.

We have years of experience working with and using dehumidifiers, so we decided to put together this guide to answer some of the most frequently asked questions about dehumidifiers and teach you a few new things you may not have known and bust a few myths along the way.

Stay tuned for regular updates to this page!

So let’s start at the beginning…

What is a dehumidifier

A dehumidifier is an electric appliance often used for climate control.

What do dehumidifiers do?

They are designed to maintain & regulate the atmosphere in an environment by removing or reducing excess moisture in the air. They also condition the air and generate airflow to prevent damp from causing issues such as mold, musty smells and condensation.

Why would someone need a dehumidifier?

When an environment that is not suited for water experiences long term exposure to high levels of humidity, the walls, flooring, ceiling and furniture can develop a musty smell, creating an uncomfortable environment that is unpleasant to inhabit.

If there is mould in the room, the need for a dehumidifier increases, as spores from mould could cause significant health issues, especially for those with allergies. Mold can even compromise the structural integrity of the building causing them to become unsafe and lose value.

Types of dehumidifier

There are 2 types of dehumidifiers; condensate dehumidifiers and desiccant dehumidifiers

Condensate dehumidifiers

Condensate dehumidifiers use a refrigerator to collect water (referred to as as condensate). While this water is usually a waste product (greywater) there are situations in which it can be turned into drinkable (potable) water.

Desiccant dehumidifiers

Desiccant dehumidifiers (known also as absorption dehumidifiers) bond moisture with hydrophilic materials such as silica gel. Cheap domestic units contain single-use hydrophilic substance cartridges, gel, and powder. Larger commercial units contain hot air recovery systems in order to remove humid air from outside the room.

Natural dehumidifiers

Some substances such as salt, sand, sawdust and cat litter act as natural dehumidifiers. These usually need frequent replacement and are not ideal as a permanent solution.

How do dehumidifiers work?

There are many different types of dehumidifer, each works in it’s own way. One of the most common types of dehumidifer is the electric refigeration dehumidifer which works by drawing the warm humid air into the dehumidifier, where it then comes into contact with cooling coils that remove the water from the air. The water is collected within the dehumidifier and the cooled dry air is expelled thus improving the overall ventilation. Some designs, such as the ionic membrane dehumidifier, dispose of water as a vapor rather than liquid.

Popular reasons for needing a dehumidifier

Poor ventilation

This is a common occurrence for old bathrooms in old buildings. Often the ventilation in kitchens and bathrooms is insufficient as an air mover, meaning that warm humid air & steam from showers and tumble driers is not allowed to escape, cool or circulate. In these situations, it is best that permanent dehumidifiers are installed.

Emergency leaks, flooding & fires

Leaks & flooding are most commonly caused by rain water due to damaged roofing or blocked guttering, pipes that have loosened or burst and poor drainage.

In the event of a fire, the most common ways to extinguish the flames is to use water or foam. These can also create humid and damp conditions if not dried appropriately.

It is in these scenarios that it would make the most sense to hire a dehumidifier, as they are likely to only be used for short periods of time.

Industrial & Commercial necessity

Large dehumidifiers are often used in commercial settings such as swimming baths, spas and ice rinks and industrial buildings such as manufacturing plants or storage warehouses.


This page is updated regularly with new content. Contact us to learn more about dehumidifiers.

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