SEER stands for Seasonal Energy Efficiency Ratio, which is a rating scale that measures the energy efficiency of an air conditioning system. The SEER rating of a unit is the cooling output during a typical cooling season divided by the total electric energy input during the same period. The higher the SEER rating, the more energy efficient the unit is. SEER ratings are standardized to ensure accuracy and consistency across different air conditioner manufacturers and models.
To calculate an ACs SEER rating, divide its cooling output by its electric energy input during a typical cooling season. The SEER rating reflects overall system efficiency on a seasonal basis, while the EER (Energy Efficiency Ratio) reflects the systems energy efficiency at one specific operating condition.
A good SEER rating is typically 14 or higher. In the northern United States, new HVAC systems must have a minimum SEER of 13, while in the South and Southwest, 14 is the minimum SEER. Older ACs have lower SEER ratings in most cases, with air conditioners from the 1990s generally rated 8-11. SEER ratings of 13-15 are considered good, 16-19 are better, and 20-24 is best.
Knowing the SEER rating of an air conditioning system is important when choosing a new unit, as substantial energy savings can be obtained from more efficient systems.
