What Is a Swamp Cooler
With simple maintenance, swamp coolers are the most efficient way to cool your home in the desert. Since swamp coolers work by the evaporation of water, the dry air around the cooler makes it work efficiently.
Evaporative cooling uses the evaporation of water to cool the air. For every gallon of water that is evaporated, about 950 BTUs go with that evaporation. How this works is when water is evaporated, the water left behind is cooler than it was initially. So the water left in the pan gets colder and colder as more of it evaporates and that water is pushed up through a tube to the pad where its blown out. This is a cyclical process that removes the heat from the air taken in by the cooler.