Contrary to popular belief there, is no rule of thumb for sizing a system to a home. Depending upon the construction of your home, one (1) ton of air conditioning can cool anywhere from 100 to 300 square feet of home. The only way to insure the size of the system you purchase will be large enough to cool your home, but not any larger than you need, is to have your home’s individual heating and cooling needs evaluated by a professional.

No. A larger system with more capacity delivers less comfort and costs more to operate. An air conditioner is at its least efficiency when first turning on. A system with too much capacity will run in numerous short cycles, turning on and off repeatedly, therefore causing it to be less efficient. Also keep in mind that an air conditioner only removes humidity when it’s running, so a system with shorter run cycles doesn’t remove humidity from the air very well.

There is no exact answer for how long your system should run during each cycle. The average air conditioner is sized to remove the heat from your home as fast as it comes in, on a 430° day. Therefore, ideally, on a 430° day the system should be able to keep up with the incoming heat, but not gain on it and be able to turn off. The cooler it is below 430°, the more the system will cycle on and off.