- evaporative coolers
Evaporative coolers are less expensive than air conditioners and you have the added benefit of fresher, moister air and no chemicals!
An evaporative cooler, sometimes called an swamp cooler, is essentially an appliance with porous surfaces that enable air to pass through. A fan inside the unit pulls outside air through the sides and into the house. To produce cool air, each porous side is fitted with a pad of water-absorbing material. Water is stored in a pan at the bottom of the cooler and a small pump lifts the water to the top of each side. The fan moves the hot outside air through the water-wetted pads, cooling the air about 20-25ºF as the air evaporates water molecules from the pads. The fan then blows the water-cooled air through the house.
Wet the back of your hand — then blow on it. Your skin surface feels cooler. That’s evaporative cooling.
Swamp coolers are popular in dry climates 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.
Swamp coolers are efficient and effective machines of cooling. As a direct replacement for air conditioning in dry climates, these coolers are an example of how we can work with nature. Being considerably less expensive than air conditioning, it almost seems that one is getting something for nothing when using a swamp cooler.
To choose the right size evaporative cooler for your home, you need to determine how many cubic feet of air per minute (CFM) the unit can pump.
If you can’t locate the CFM number on your evaporative cooler or in the owner’s manual, the following formula will help you calculate it:
* Multiply the square footage of your home by the average height of the ceiling (in feet).
* Divide by two (air changes per minute).
Example: 1,625 sq. ft. x 8 ft. (ceiling height) = 6,500 CFM/2
