8 Best Evaporative Coolers To Buy

Buying an Evaporative Cooler

Evaporative coolers, AKA swamp coolers, use an electric-powered fan to draw hot, dry air through a dampened pad and blow the cooled air out into the space, indoors or out. This relatively simple process consumes much less energy than a standard air conditioner and doesn’t require ozone-damaging refrigerants to work.

Evaporative coolers are also less expensive to install and maintain than central air conditioning. If you’re considering an evaporative cooler, here are some details keep in mind:

CFM Rating: Every model of evaporative cooler has a CFM (cubic feet per minute) rating, which indicates how much air the unit can move. The higher the CFM rating, the larger the area it can cool.

To determine the CFM rating you need to cool your space, calculate the cubic feet of space you want to cool (length in feet x width in feet x height in feet = cubic feet) and multiply that total by the number of air changes per hour (ACH) you prefer. The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) suggests from five to nine air changes an hour for residential rooms. Then divide that total by 60, per minute. The result is the CFM rating you should look for when purchasing your cooler.

Size of the Space: Some evaporative cooler models also list the square footage the unit can cool. This guideline is less precise than the CFM because it doesn’t take into account the height of a space, but it can still be a useful guideline.

Water Tank Capacity: A large water tank keeps your evaporative cooler running longer without the hassle of refills. Some outdoor evaporative coolers have a water intake hose option for continuous water flow into the tank.