Heating and Cooling by the numbers

Why are the rating numbers of furnaces and air conditioners important?

Rating numbers indicate the efficiency of heating and air conditioning equipment and are directly related to the amount of energy a specific model uses. The higher the rating, the more efficient the product, and the lower your heating and cooling bills can be. The federal government establishes rating guidelines and sets minimum efficiency levels.

For cooling equipment, the rating is called SEER (Seasonal Energy Efficiency Ratio). The higher the SEER number the more efficient the unit.

For heating equipment, the rating is called the Annual Fuel Utilization Efficiency (AFUE) and it is given as a percentage. For example- National Home Services installs 95% ENERGY STAR qualified furnaces.

How is the AFUE of furnaces calculated?

The AFUE is a complex calculation, derived from performance parameters that are measured under laboratory conditions. These include a set of temperatures, the energy consumption, and a few other performance parameters.  In general, it represents the percentage of heat in the incoming fuel which is converted to space heat.

How is SEER calculated?

The Seasonal Energy Efficiency Ratio (SEER) is calculated by the total cooling output of an A/C or heat pump during an average cooling season divided by the total electricity input during the same period of time.

Hope you enjoyed learning more about how we calculate the efficiency of your home equipment. Remember the higher the rating, the more efficient the product, and the lower your bills can be!