An evaporative air cooler is an air conditioner that uses the power of evaporation to cool the air temperature. When water evaporates, it changes from liquid to gas. When it does so, the highest-energy particles leave the water first, which causes the temperature to drop. That's why a damp cloth on your forehead feels great on a hot day. As the water evaporates, it helps reduce the temperature of the head.

Similar scientific standards apply to the evaporative cooling process when it comes to the air in your home. In dry climates, a simple evaporation process can help reduce air temperature. If you've ever missed the air around you to feel cool on a hot summer day, you've probably felt it firsthand. Evaporative air conditioners take a similar idea, but add technology to make the process more efficient and less messy than just spraying water around the room and hoping for the best.

Evaporative cooling systems require and mechanize the necessary evaporation to effectively reduce the temperature of the air in your home. Typically, the machine will include a fan, thick pad, water supply, and some additional controls for calibrating the results. Fans draw hot, dry air into machines and through cooling pads.

Evaporative cooling systems require the necessary evaporation and mechanize it to effectively lower the temperature of the air in your home. Typically, the machine will include a fan, thick pad, water supply, and some additional controls for calibrating the results. A fan draws hot, dry air into the machine and across the cooling pad.