How to Choose an Evaporative Swamp Cooler

As the summer approaches, people who live in hot, dry areas turn to evaporative coolers to stay cool and comfortable. They are relatively inexpensive, use less electricity than conventional air conditioning units and require little to no installation. In dry climates, they're great for cost effectively lowering ambient temperatures. All you need to operate an evaporative cooler is sufficient space for the unit, an electrical outlet, water to cool the cooling media, and adequate airflow and ventilation.

Is an Evaporative Cooler Right for You?

The first thing to consider when purchasing an evaporative cooler is determine whether you live in the right type of climate. In the right conditions, a swamp cooler can lower the temperature by as much as twenty degrees Fahrenheit. Evaporative coolers use simple technology and electrical power to provide cooling effect. A motor pumps water to soak fibrous pads while a separate motor powers a fan that pushes air through the pad. If you live in an arid climate the entering air will be hot and dry and water will be evaporated. The ambient temperature is decreased and the environment is made more comfortable because the air being re-circulated is chilled and somewhat damp.

What Size Evaporative Cooler Do You Need?

The next most important thing is choosing the proper sizing for your evaporative cooler. An evaporative cooler must be the proper size to effectively cool. For example a small portable unit will not adequately cool a large-sized room. Evaporative coolers are rated by CFMs (the cubic feet per minute of air that the cooler can blow into your home). The formula to determine how many CFMs you need is quite simple. Figure out the amount of cubic feet of space you want to cool first. Then, divide that number by two. The quotient is the CFM rating for the properly sized evaporative cooler for you.

How Much Maintenance Do Evaporative Coolers Require?

Before purchasing an evaporative cooler, keep in mind that they may require more maintenance than a portable air conditioner would. This maintenance consists of refilling the water supply, draining the unit and ensuring that the pads are clean.

What Kind of Pads Do Evaporative Coolers Use?

One last important consideration before purchasing an evaporative cooler is what kind of pad it uses. Most pads are made of excelsior (wood wool or aspen fiber) inside of containment net. Modern materials such as some plastics and melanin paper are also entering use as cooler pad media. The good thing about the excelsior pads is that the wood absorbs some of the water, which allows wood fibers to cool passing air to a lower temperature than unnatural materials. The thickness of the pads affects the cooling efficiency of the pads. The thicker the pad, the longer the air contact. This means an eight inch thick pad with its increased surface area will be more efficient than a one inch pad.