How Evaporated Coolers Work
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An evaporated cooler, also commonly referred to as a swamp or desert cooler, is an energy-efficient cooling device that utilizes the power of evaporation. Through using this natural process of evaporation, evaporated coolers can dramatically lower the temperature of hot, dry air. Evaporated coolers also add moisture to the air, which again is beneficial in warm, dry environments. But just exactly how does an evaporated cooler work?
Basic Function
The basic principal behind evaporative cooling is that the evaporation of a liquid into the surrounding air cools the air as well as any object with which it comes in contact. When water evaporates, heat is pulled from the air. This naturally leaves the resulting air cooler. The amount of heat pulled from the air during the evaporative process can vary, based on a few different factors. The most important factors for an evaporated cooler are the relative humidity levels and overall air temperature. Evaporated coolers harness this evaporation process, and work best in very warm climates with little or no humidity.
Evaporated coolers typically will consist of a boxed fan and water-soaked pads. While these are the basic essentials for an evaporated cooler, much more sophisticated systems will include different features, including an electric water pump, carbon air filters and even an automatic timer and shut-off mechanism. The evaporated cooler's fan draws in air, which is then passed through a type of pad that has been soaked with water. As the air passes through this fan, the water evaporates, removing the heat from the air. The cooler air is then redistributed throughout the room or area, providing a cooling effect.
To maximize the cooling power of your evaporated cooler, you should ensure there is adequate circulation in the area. Since these units take dry air and add moisture to it, eventually your area will become muggy if the air is unable to circulate, and the evaporative process will not work. While this is not an issue when utilizing an evaporated cooler outdoors, it can cause problems inside. To combat this, simply open a window and/or door to your room, which will allow for the air to circulate properly, enhancing the cooling effect of your unit.
Applications
As mentioned, an evaporated cooler will work best in very dry air, especially in warm temperatures. Due to the evaporative process, these coolers will not function as well in areas with higher relative humidity. Evaporated coolers are commonly used in the Southwestern portion of the United States, as the desert-like climate is perfect for these units. What makes them so popular is that these units use much less energy than a typical air conditioner, meaning they cost less to operate, and have a much lower environmental footprint. Additionally, evaporated coolers also require much less maintenance than the normal air conditioner unit.
Evaporated coolers can be used to cool spaces as small as a bedroom or closet, or as large a space as an entire house or barn. As an added benefit, an evaporated cooler can also help to filter the air as well as remove smoke and pollution from the surrounding area. These units are also commonly used in outdoor areas, such as patios and gardens, where air is easily circulated. Essentially, an evaporated cooler can be used in just about any location that requires cooling -- as long as the air is warm and humidity levels are low.