How to Operate a Swamp Cooler

How to Operate a Swamp Cooler

Evaporative coolers offer energy-efficient cooling in dry climates

By Cathy McClellan

Swamp Cooler on Roof
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People who live in the drier air areas of the United States benefit from the ability to use swamp coolers, also called evaporative coolers. Swamp coolers are installed in the windows of your home and work by blowing wet air into the room, effectively cooling the room. Swamp coolers are more energy efficient to operate than a central air conditioning.

  • What You Need to Know
  • While swamp coolers are best-known for their efficacy in dry and hot climates, they are also sometimes the best solution in humid areas. Evaporative cooling is a proven solution for many commercial spaces characterized by humid air and small space -- such as kitchens, dry cleaners, and greenhouses.
  • You only need a swamp cooler, electricity and water to operate the cooler.
Keeping Your Home Cool

Step 1:

Purchase the correct size of swamp cooler for your cooling needs. Swamp coolers are available in a variety of sizes and blower options. To figure size requirements, evaporative coolers use cubic feet per minute (CFMs) of air, multiply the square feet of the home with the height of the ceilings and then divide that total by 2. The result will be the CFM rating. For example, multiply a 1500 square foot home with 8-foot tall ceilings for a total of 12,000 feet. Divide 12,000 by 2, which equal 6,000 CFMs. Install the swamp cooler according to manufacturer's directions as the installation directions often different depending on the model and your home's windows.

Step 2:

Fill the bottom of the swamp cooler to the fill line with water. Wet the three pads that make up the walls of the swamp cooler completely with water. This step makes the pads wet quicker so that the swamp cooler can begin cooling the room quickly after it is turned on. Some models will have a setting to turn the fan on for the specific purpose of wetting the pads before turning the cooler on.

Step 3:

Open one or two windows approximately one to two inches in different areas of the home away from the swamp cooler. This will draw the cool air into other parts of the room. Use ceiling fans as well to circulate the air in rooms. Turn the swamp cooler on by turning the appropriate knobs for the pump that circulates the water inside the swamp cooler to keep a continuous flow of water to the pads.

Step 4:

Run the swamp cooler as needed. Lower the speed on the fan once the home has reached your desired indoor temperature. It may be necessary to turn the fan to a higher setting again when the outside temperature is the hottest.

Step 5:

Turn the pump off on cool evenings and let the swamp cooler cool the home with the fan placed on any setting, which will blows outside air into the home. Depending on your preference, you can run the swamp cooler 24 hours a day or only when desired.

  • Tips & Warnings
  • Check the pads and water level periodically to ensure the water is not too low for the pump to operate.
  • Keep leaves and debris out of the bottom of the swamp cooler so the pump will not clog.
  • Drain the water and clean the bottom of the cooler and place a cover over the inside grates for winter storage.

About the Author

Cathy McClellan is a regular contributor to DexKnows.

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