HVAC Glossary

Let's start 8at the beginning: HVAC stands for Heating, Ventilating and Air Conditioning and are the initials often used to describe the industry that produces the equipment that brings comfort to your home.

AFUE - This is a percentage measurement of a furnace's heating efficiency. The U.S. Government's minimum efficiency level is 78%. The higher the AFUE, the more efficient the furnace. The initials stand for Annual Fuel Utilization Efficiency.

Energy Star - A voluntary partnership between the U.S. Department of Energy, the U.S. Environmental Protection Agency, product manufacturers, local utilities and retailers. Partners help promote energy-efficient products by labeling products with the Energy Star logo and educating consumers about the unique benefits of energy-efficient products. In addition to labeled products, Energy Star offers voluntary partnerships which promote energy efficiency, reduce air pollution, and save money for businesses large and small. Each year, these partnerships save over $1 billion in energy costs while also cutting air pollution. When properly installed, Energy Star labeled products can save consumers 10-40% on heating and cooling bills each year.

SEER - This is a measurement of the efficiency of cooling products. The U.S. Government's minimum-efficiency level is 10 SEER for split systems and 9.7 for packaged units. The higher the SEER, the more efficient the cooling product. SEER stands for Seasonal Energy Efficiency Rating.

HSPF - This is a measurement of a heat pump's heating efficiency. There is no governmental minimum rating. The higher the HSPF, the more efficient the heat pump's heating performance. HSPF stands for Heating Seasonal Performance Factor.

A Note About Efficiencies: When you're getting ready to replace an older heating or cooling system, it's very important for you to get a Load Calculation done by your dealer/contractor. The greater the difference between the efficiency of your old system to the new system, the more likelihood that the dealer will recommend a smaller sized unit. This should not cause alarm, as the dealer, by running a Load Calculation, will be able to accurately size the system to the load in your home. It can be quite detrimental to equipment if the units are too large for the load in your home - they can start to "short cycle" (they run often but for very short periods of time, because they are pumping out too much heat/cooling and reach the thermostat's setting too quickly), which can shorten the life of the unit dramatically.

This means that at the lower rating, the furnace is capable of producing 113,000 BTU's of usable heat per hour to heat your home. And, if it ran constantly for one hour, it would consume .85 gallons of oil. If, however, your dealer sets up your oil furnace to operate at the higher rating, it would produce 125,000 BTU's of usable heat per hour, and use 1.00 gallons of oil. Whether your oil furnace is set up by your dealer to operate at the higher or lower rating depends on that all important Load Calculation. By properly sizing the furnace to your home, you will be assured of maximum comfort, energy savings and extended equipment life.