SEER, brief for Seasonal Energy Efficiency Ratio, is just a metric representing the energy efficiency of ac units. Adopted in 1979 and today prominently displayed on the Department of Energy’s yellow EnergyGuide sticker attached to each of new air-conditioning units, the SEER rating offers an at-a-glance means for consumers to comparison shop among different makes and models of cooling processes. SEER calculates the amount of heat energy extracted from a home at BTUs divided by the kilowatt hours of electricity consumed. Units are tested in a range of outdoor temperatures in 67 degrees Fahrenheit to 102 degrees Fahrenheit, and effects are averaged within the 1,000 operating hours believed to be typical for a 125-day annual cooling season. The higher the ensuing SEER numeral, the more energy-efficient the cooling function of this unit.
Central Air-conditioning
When SEER was adopted, the average rating for a central air conditioner was SEER 6. In the decades since, air conditioning technology steadily progressed, energy conservation awareness rose, and the SEER minimal conditions were revised. In 1992, federal law mandated a minimum SEER rating of 10 for all central air-conditioning units sold at the U.S.. In a revision issued in 2006, the minimum SEER rating was upped to 13. Central air conditioner using a SEER 13 score are considered standard efficiency units, while those using SEER 14 or over are classified as high-efficiency. The evaluations for high-efficiency central air conditioners top out about SEER 23.
Heat Pumps
A heat pump supplies both cooling and heating. When operating in cooling system, heat pump efficiency is rated by the SEER scale. As with central air, the identical national minimum SEER 13 applies to all heat pumps sold in the United States, and heat pumps with heat modes rated as large as SEER 24 are readily available. Efficiency of the heat function in a heat pump is rated by the HSPF, short for Heating System Performance Factor. Generally, heat pumps with higher SEER evaluations will even have high HSPF evaluations.
Ductless Mini-Splits
Ductless mini-splits utilize heat pump technology into state individual rooms without ports. The indoor component of a ductless mini-split system contains a compact atmosphere air handler containing a coil and compressor fan. The handler is linked by 2 refrigerant lines that stretch through an outside wall to an exterior casing which holds the compressor and outdoor coil. A single outdoor unit can serve up to four indoor air handlers in individual rooms. Unlike a central air-conditioning system in which one air handler accomodates the entire home and disperses cool air through ductwork, ductless mini-splits typically offer the highest available SEER, together with SEER ratings as high as 26.
Window Air Conditioners
Window air conditioners are rated by a simplified variant of SEER named EER, brief for Energy Efficiency Ratio. Like SEER, this figure expresses the power extracted from a home expressed in BTUs divided by the kilowatt hours of electricity consumed at one fixed outdoor temperature at one time. The calculation isn’t averaged over variable temperatures during a 1,000-hour cooling season (such as SEER is), thus EER is recognized as to be less accurate predictor of true efficiency in real world conditions. The federal minimum EER rating for window air conditioners is 9.8, and the most efficient available units offer EER ratings of just over 11.