Proper sizing, selection, and installation are keys to cost-effective operation. Your residential system is designed using guidelines required by the International Code Commission Building Codes and two groups—the Air Conditioning Contractors of America (ACCA) and the American Society of Heating, Refrigerating, and Air Conditioning Engineers (ASHRAE) publish calculation procedures for sizing central air conditioners. How big should your air conditioner be? The size of an air conditioner depends on:
* How large your home is and how many windows it has;
* How much shade is on your home's windows, walls, and roof;
* How much insulation is in your home's ceiling and walls;
* How much air leaks into your home from the outside; and
* How much heat the occupants and appliances in your home generate.
An air conditioner's efficiency, performance, durability, and initial cost depend on matching its size to the above factors.