What is SEER?

"SEER", Seasonal Energy Efficiency Ratio, is most commonly used to measure the efficiency of a central air conditioner. It measures how efficiently a cooling system will operate over an entire season. The higher the SEER, the more efficient the air conditioner. Technically speaking, SEER is a measure of equipment the total cooling of a central air conditioner or heat pump (in Btu) during the normal cooling season as compared to the total electric energy input (in watt-hours) consumed during the same period.

What is EER?

"EER", Energy Efficiency Ratio is a measure of how efficiently a cooling system will operate when the outdoor temperature is at a specific level (95oF). In technical terms, EER is the steady-state rate of heat energy removal (i.e. cooling capacity) by the product measured in Btuh divided by the steady-state rate of energy input to the product measured in watts. This ratio is expressed in Btuh/watt. The higher the EER, the more efficient the air conditioner.

Both SEER and EER are included in the ENERGY STAR specification because each rating indicates the energy efficiency of the product under different operating modes. SEER rating more accurately reflects overall system efficiency on a seasonal basis and EER reflects the system’s energy efficiency at peak day operations. Both ratings are important when choosing a product.
As of January 2006, all air conditioners sold in the United States must have a SEER of at least 13. ENERGY STAR qualified Central Air Conditioners must have a SEER of at least 14, and an EER of at least 11 for single package equipment and 11.5 for split systems.

Earning the ENERGY STAR means products meet strict energy efficiency guidelines set by the US Environmental Protection Agency and the Department of Energy.

• ENERGY STAR qualified geothermal heat pumps use about 30% less energy than a standard heat pump.
• They are quieter than conventional systems. Remember, saving energy prevents pollution.
• By choosing ENERGY STAR and taking steps to optimize the performance of your heating and cooling equipment, you are helping to prevent global warming and promoting cleaner air while enhancing the comfort of your home.

You may also be interested to know:

• Though these products can be more expensive to purchase up front, the cost difference will be paid back over time through lower energy bills.
• When buying new equipment, sizing and installation are as important as product quality.
• You can get better heating and cooling performance at home with ENERGY STAR home sealing (insulation and air sealing) and duct sealing.
• Consider regular maintenance to maintain your heating and cooling system performance.