Differences Between an Air Cooler & an Air Conditioner

How Coolers Work

• A cooler cools a room by absorbing hot air through pads around the sides of the cooler that are soaked by a water pump. A fan draws outside air through the absorptive pads and, as the water in the pads evaporates, it causes the air in the room to cool and adds moisture to the air.

How Air Conditioners Work

• Air conditioners cool air by removing heat from the air inside to the outside. Freon gas is a coolant that becomes hot when it is compressed in the air conditioner's compressor. This hot gas leaves the compressor through a set of coils and flows into the condenser to dissipate its heat and turns the gas into a liquid. The fluid leaves the condenser and goes into the evaporator where it changes back to gas. The gas evaporates into a cool, low pressure gas, and, as it does, heat is extracted from the air around it, thus cooling the air.

Pros and Cons of Coolers

• A cooler costs about half as much as an air conditioner that cools the same size area with units that can cool 750-square feet for as low as $275 as of August 2011. Additionally, coolers use as much as 75 percent less electricity as air conditioners -- and even more in hotter climates. Moisture brought into the air from coolers helps to keep wood furniture from drying out, and the absorptive pads trap some dust and pollen.

  Coolers depend on dry outside air to operate effectively; otherwise, hot air is blown into the room. Likewise, a cooler must exhaust as much air as it takes in to remain effective. Therefore, at least one window must be kept open or the temperature of the air released by the cooler rises. Additionally, according to the California Energy Commission, using a cooler can cause you to use up to 15 gallons of water a day because coolers require water to keep the pads wet.

Pros and Cons of Air Conditioners

• Air conditioners dehumidify and cool the air in a room without having to depend on dry outside air. Air conditioners help to control allergens, such as dust and pollen, by regulating indoor temperatures and humidity levels. Air conditioning works best when the windows are closed, so you don't need to open any windows. Additionally, air supplied by an air conditioner is cooler than that supplied by a cooler.

  An air conditioner is more expensive than a cooler. As of August 2011, a portable residential air conditioner that can cool up to 450 square feet costs from $400 to $650. An old air conditioner may not run efficiently, thereby raising your utility bills. Additionally, air conditioners require more ductwork than coolers.