Myth: The bigger the air conditioner, the better it cools the house.
Fact: Air conditioners cool and dehumidify. An oversized air conditioner can quickly cool a home but results in the air conditioner frequently cycling on and off, which doesn’t allow it enough time to remove moisture and may make the house feel clammy. A properly sized A/C will operate for a longer period of time during the hottest days, which will remove that uncomfortable moisture. Although a properly sized unit will run longer, it will be more efficient and use less energy.
Myth: The square footage of the house is all that’s needed to size an air-conditioning system.
Fact: A good load-calculation program takes into account window types, window orientation and window shading; insulation of the ceiling, walls and floor; air leakage; and many other factors, such as the color of the roof and the number of the home’s occupants. Using the square footage of a home to size an air conditioner is outdated and will almost always yield an oversized system. Don’t use a contractor who wants to size your unit solely on the square footage of your house. Require a Manual J or equivalent analysis before purchasing an air conditioner.
Myth: Setting your air-conditioner thermostat to its lowest setting will cool the home faster.
Fact: The thermostat is not a throttle; setting it lower than necessary will not cool the home any faster.
— Information courtesy of the Arkansas Energy Office, www.arkansasenergy.org