What Is A Swamp Cooler?

• A swamp cooler is an evaporative cooler, also called a desert cooler or air cooler, used to cool air. Through the use of the natural phenomenon of water evaporation, warm air is cooled and blown into a room or home, cooling the occupants. The process relies on the contrast of wet-bulb (humidity) and dry-bulb temperatures (thermometer temperature). The greater the contrast, the more benefit the cooler will be to the occupants. But if the two rise together, the benefit begins to lessen until there is no reason to turn on the swamp cooler.

• Parts of a Swamp Cooler

• Swamp coolers have a metal case, or frame, that fits over the cooler parts. The frame is box-like and vented and holds an electric motor with pulleys, a fan or blower and a water pump. The inside walls of the frame are lined with pads made of cellulose. These pads a replaced every season with new ones. When the swamp cooler is turned on, these pads are continually wetted with water by a water pump. A fan inside the box frame pulls warm, outside air through the wet pads which automatically cools the air by evaporation. The cooled air is then released through vents into the house or room. The cooled air is generally around 20 degrees F cooler than the outside air. If humidity outside is 10 to 20, percent then the cooler can cool the air up to about 30 degrees cooler. The higher the humidity goes, the less effective the cooler becomes. Swamp coolers can be mounted on top of the roof or at windows or openings on the sides of buildings.

  Climates for Swamp Coolers

• Dry climates are best for swamp cooler use. Swamp coolers are popular in the southwest United States due to the consistently low levels of humidity. Evaporative cooling is a dynamic system, meaning its effectiveness changes according to external temperatures and levels of water in the air.