Difference between a Dehumidifier and an Air Conditioner

Published on December 6, 2016

So the time has come to invest some money in your home and make it more comfortable. An air conditioner would be great, but so would a dehumidifier. Do you know what kind of device you need? Before reaching for the phone and calling a home ventilation and air conditioning expert, make sure you know at least the basics about the two. This will help you better understand his explanation and you will know better what you need and what to ask for.

Definitions

Dehumidifier vs Air Conditioner
A Maytag dehumidifier

A dehumidifier is a home appliance that reduces the level of humidity in a room by extracting the water from the conditioned air. The resulting water is discarded. It is best used in small, unventilated rooms and in humid areas.

There are several reasons why people would choose to get a dehumidifier. They might want to protect a room from dampness, remove a musty odor, or protect their bodies from the damages of allergies and dampness: stuffy nose, itching, wheezing, irritation or watery eyes.

Also, there are a lot of things to consider when looking to buy a dehumidifier. The capacity of the room it is supposed to dehumidify dictates the power or size of the dehumidifier. Storing space is another issue you must consider, especially since a dehumidifier is meant for small rooms.

The most common option is refrigerated dehumidification which means that a fan draws the air over a refrigerated coil. The water extracted is condensed and removed and the air is reheated by a condenser coil and released warm into the room. There is also the option of the desiccant dehumidifier which is chemical based, and of the electronic one. 

air conditioner
A mini split air conditioning device

An air conditioner is a home appliance that removes heat and humidity from a confined space, cools it, then returns it to the room. The main parts of the air conditioner are the compressor, the condenser and the evaporator. The compressor and the condenser are usually placed outside, while the evaporator is placed inside. The water collected by air conditioners is let drip outside the room. More efficient models have the water evaporate over hot coils.

You can choose between window or portable air conditioners, split air conditioners and evaporative coolers. As far as general air conditioning goes, there are various types of devices intended for use for specific types of spaces. There are air conditioning options for cars, for apartments and large houses alike, and for industrial spaces with lots of computers and industrial tools working in the same space.

Dehumidifier vs Air Conditioner

So what is the difference between a dehumidifier and an air conditioner?

Air conditioners cool the air in a room, whereas dehumidifiers reduce the humidity. One is for comfort (air conditioners), while the second has medical applications (dehumidifiers). Since dehumidifiers are derived from air conditioners, they are built and operated roughly the same. They differ in the temperature of the air returned to the room: cooled over the refrigerated coil in the case of air conditioning and reheated in the case of the dehumidifier.

Water evacuation is another point of difference. Air conditioners let it drip outside through connected drainage systems. Dehumidifiers may be tied to the plumbing system of the building or may have collection devices that need to be emptied from time to time.

Comparison Chart

DehumidifierAir conditioner
A home appliance that extracts excess humidity from a roomA home appliance that extracts heat from a room
Can have medical applicationsIs designed for providing comfort
Air is reheated before it is returned into the roomAir is cooled before it is returned to the room
Water needs to be evacuated inside, either through a connection to the general drainage system of the house or by periodically emptying an inner containerWater is let drip outside the house
There are three types of dehumidifiers: mechanical, desiccant or electricThere are three types of air conditioners: portable air conditioners, split air conditioners and evaporative coolers