Energy Efficiency
Understanding the EER, SEER and HSPF Ratings
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When shopping for heating and cooling systems, you may come across two important ratings: EER and SEER. Both ratings are used to determine the energy efficiency of air conditioning units, and can help you choose the most cost-effective and energy-efficient system for your home.
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EER (Energy Efficiency Ratio) measures the cooling capacity of an air conditioning system per unit of energy consumed. This rating is calculated by dividing the cooling output (measured in BTUs) by the energy consumption (measured in watts) of the unit under test. The higher the EER rating, the more energy-efficient the system is. A higher EER rating also means lower energy bills for the homeowner.
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SEER (Seasonal Energy Efficiency Ratio) measures the efficiency of air conditioning systems over an entire cooling season. This rating takes into account the performance of the unit under different weather conditions, including the temperature and humidity. SEER is calculated by dividing the total cooling output (measured in BTUs) over a cooling season by the total energy consumption (measured in watt-hours) during the same period. The higher the SEER rating, the more efficient the system is over the entire cooling season.
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HSPF stands for Heating Seasonal Performance Factor, which is a measure of the heating efficiency of a heat pump system. It is calculated by dividing the total heating output of the system by the total electrical energy consumed during the same heating season.
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The HSPF rating takes into account the performance of the heat pump over the entire heating season, including its efficiency at both full load and partial load conditions. It is a useful metric for comparing the energy efficiency of different heat pump systems, and can help consumers make informed decisions about which system is best for their needs.
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In general, a higher HSPF rating indicates a more energy-efficient system, which can result in lower energy costs over time.
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When choosing an air conditioning system for your home, it's important to consider the EER, the SEER and HSPF ratings. While higher-rated systems may cost more initially, they can save you money in the long run by reducing your energy bills.
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EER = Cooling output (in BTUs) / Energy consumption (in watts)
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SEER = Total cooling output (in BTUs) during the cooling season / Total energy consumed (in watt-hours) during the same period
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HSPF = (Total Heating Output during the Heating Season) / (Total Electrical Energy Consumed during the Heating Season)