The ABCs of Air Conditioning - Energy Efficiency Ratings

For most homeowners energy efficiency and lower utility bills are at the top of the list when deciding on a new air conditioner. When researching cooling systems you're likely to run across a lot of industry alphabet soup. While this alphabet soup can be bit confusing at first, they're meant to provide a simple scale to compare which systems that offer the highest efficiency and lowest energy costs. Here are two of the most common measurements of energy efficiency.

SEER Ratings

The Seasonal Energy Efficiency Ratio (SEER) is a measure of efficiency for air conditioners. A high SEER number means more energy efficiency, and lower cost to operate. All new air conditioners have a 13.0 SEER rating or better. The most efficient systems can achieve SEER ratings over 20.

AFUE Ratings

For gas furnaces, the Annual Fuel Utilization Efficiency (AFUE) rating is a common measure of energy use and efficiency. The AFUE rating tells you how much of the fuel used by your furnace is used to actually heat your home and how much is wasted. The higher the AFUE rating, the greater the efficiency. For example, a 90% furnace creates heat, 90% of which is used directly by the home with 10% lost, generally as a result of venting. Some newer furnaces have an AFUE rating that exceeds 98%.