How do I know if my A/C system is the right size for energy efficiency? 
Tom in Prescott Valley

Tom, the only way to tell is to have a qualified (licensed, bonded and insured) HVAC professional come and inspect your home.  They can provide what is called a “Heat Load” calculation.  This is determined by the square footage, ceiling height and number of windows and doors in your home.  If an upgrade unit is based on a retrofit sale, there normally is no charge to the Load Calculation.  If Load Calculations are required for a new build, there is usually a small per square foot charge for the calculation.