What is a swamp cooler?

A swamp cooler (more formally called an evaporative cooler) is a simple device that cools by evaporation. It's essentially a large box-like construction that contains a big fan (higher volume, lower pressure) and is surrounded on the sides by water-wetted pads (batting), usually made of cedar shavings or cellulose. The fan pulls the hot outside air through the dripping pads (which are continually soaked by water which is delivered by a pump), and the air is cooled by the evaporation of water in the pads. This reduces the temperature of the air by about 20 ºF or so. The fan then blows the water-cooled air through the house.

Swamp coolers are popular in the southwest because they are relatively inexpensive, use a quarter as much electricity as a refrigerated unit, are easy to maintain by the average do-it-yourselfer, and add a comfortable level of humidity to the dry desert air.

First answer by Plumbster. Last edit by Quirkyquantummechanic. Contributor trust: 729 [recommend contributor]. Question popularity: 19 [recommend question]