How To Make Swamp Coolers Produce Cooler Air

If you want to stay cool and keep energy costs down, a swamp cooler does just that. A swamp cooler is ideal for dry climates with a steady low humidity.

Swamp coolers work by circulating air over cooling pads. However, you may find that your swamp cooler isn't getting the air cold enough for you.. Here are tips to make your swamp cooler produce cooler air.  

Figure CFM (Cubic Feet Per Minute) Rating

The size of the cooler can make a difference in cooler air. CFM measures how many cubic feet of air the cooler can circulate in one minute. Measure the area of the room, and multiply this by ceiling height. Divide the result by two. 

For example, if the area is 1,000 square feet and the ceiling height is 10 feet, multiply 1,000 by 10 to get 10,000. Divide 10,000 by two to get 5,000. You need a cooler with a 5,000 CFM rating to cool that room. 

Decrease Humidity

If the room is too humid, or if the outside humidity is fifty percent or more, the swamp cooler won't be effective. Decrease humidity in the following ways:

  1. Raise a window on the opposite ends of the house from the swamp cooler about two inches to create a cross breeze. Ensure the windows you open are across from one another. In larger rooms, you may need to open the window more than two inches.
  2. Some plants naturally lower humidity. Cacti and Boston ferns are two plants that lower humidity. Set the plants in small pots around the room, in sunlight. Other plants that decrease humidity include Reed Palm, Peace Lily, and English Ivy.

Maintain the Unit

  1. Ensure the pads are clean and not damaged. Dirty or damaged pads will prevent the unit from working effectively. The pads should be kept moist.
  2. Don't let the tank get empty. Check the tank each week, and keep it filled so the pads stay moist. 
  3. Let the pump run ten minutes before you turn on the fan. This will make air colder immediately when you turn on the fan.
  4. Check for clogged or damaged water filters, and replace them, if needed.  
  5. Don't operate you central air and swamp cooler at the same time, or they counteract each other.

Set up a dehumidifier in areas with no windows. If you swamp cooler leaks, or it still doesn't run effectively, contact an HVAC service. For more information on maintaining your cooling equipment, check out websites like