Heating and cooling product manufacturers use a few standard ratings to accurately evaluate the efficiency of home heating and cooling systems. Different ratings are used to evaluate different product types, but a higher rating always indicates higher efficiency. It is important to remember that these ratings are averages calculated over a complete heating or cooling season. The most commonly used ratings are:
Seasonal Energy Efficiency Ratio (SEER) measures the efficiency of your air conditioner or heat pump during the cooling season. It is a ratio of the unit’s cooling output divided by the total electric energy input during the cooling season. The ratio is expressed as a number, similar to your car’s miles per gallon (MPG) rating. Just like your car’s MPG rating, a higher SEER rating indicates higher efficiency lower energy bills.
Heating Seasonal Performance Factor (HSPF) measures the efficiency of your heat pump during the heating season. Similar to the SEER rating for your heat pump’s cooling functions, HSPF represents the heat pump’s total heating output during the heating season. Again, it’s expressed as a number like your car’s MPG rating, with a higher HSPF rating equating to higher efficiency and lower energy bills. In general, the heat pump’s HSPF heating rating will be lower than it’s SEER cooling rating.
Annual Fuel Utilization Efficiency (AFUE) measures the efficiency of your gas furnace. It measures the amount of heat actually delivered to your house compared to the amount of fuel supplied to the furnace. It is expressed in a percentage with a higher percentage indicating higher efficiency and lower energy bills.
If you have any additional questions about your system’s ratings, contact your local HVAC contractor.