Evaporative Cooler (Swamp Cooler)

Evaporative coolers, commonly called "swamp coolers," offer an energy-efficient cooling alternative – but only in dry climates. They're popular in Arizona, Nevada, New Mexico, and parts of California and Colorado where humidity rarely exceeds 30%.

IMPORTANT FOR NASSAU COUNTY HOMEOWNERS: Evaporative coolers are NOT recommended for Long Island's humid climate. Our summer humidity typically ranges from 50-80%, far too high for evaporative cooling to function effectively. At these humidity levels, a swamp cooler will simply blow warm, damp air into your home.

We include evaporative coolers in this guide for completeness and for readers considering homes in dry Western states. In those climates, they offer compelling advantages: 75% lower electricity costs than AC, fresh outdoor air circulation, and no refrigerants to harm the environment.

The technology is simple and proven – humans have used evaporative cooling for thousands of years (think wet cloth in front of a fan). Modern units add motors, ducts, and controls, but the principle remains the same.

For Long Island and the Northeast generally, stick with refrigerated air conditioning – central AC, heat pumps, or mini-splits. These systems work regardless of outdoor humidity.

Evaporative coolers draw hot, dry air through water-saturated pads. As water evaporates, it absorbs heat from the air, cooling it by 15-40°F depending on humidity levels. The cooled air is then blown into your home. This process works best when outdoor humidity is below 30%.