Air coolers are devices that use water to cool the air. Some homes develop humidity, which air conditioners tend to reduce. However, other areas are already dry and hot, and air conditioners can make matters worse. However, air coolers do not reduce the humidity of the home, thus allowing the homeowner to not only reduce the temperature but also increase the humidity. Hot air touches the water and transfers heat to the water. Some of the water evaporates and the cooled air blow into the home.

Coolers use water instead of refrigerants to cool a home.

On-site Water

Air coolers must have water on site as the coolant for the air cooler. Homeowners might not always have access to on-site water, forcing them to bring water to the site through pipes or other means, which can become expensive in some areas.


The vent on the air cooler has a fan that blows the cooled air into the home. In many cases, when the home has mild weather, the homeowner can set the air cooler to vent-only, which turns the air cooler into simply a fan that directs air to the occupants, cooling them. The vent option does not waste as much energy and does not need a source of water to function.

Cooler Pads

Air coolers have pads that absorb water and allow as much air as possible to flow through them. These pads serve as the main medium for cooling the air and thus cooling the home. These pads are made out of pliable aspen wood fiber or special cellulose papers. Synthetic versions of the natural pads last longer but do not hold as much water as the natural versions. They must resist mildew and foul smells since water serves as an ideal breeding ground for mold.


Water distribution features take water from the on-site source and continually run the water over the pads so that they can remain saturated; otherwise, the water will evaporate too soon. Pumps and motors power the flow of water into the water distribution channels. The pumps must shut off automatically when they do not have enough water to power the pump, or the pumps will overheat and sustain damage. The motors are either axial or centrifugal. Some of these motors need yearly lubrication while other motors have sealed bearings that eliminate the need for yearly maintenance. Homeowners who want quiet air coolers will need belt drive motors though direct drive motors have more efficiency and do not break down as often.