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What is SEER rating and how is it calculated?


According to the U.S. Department of Energy (DOE), about three-quarters of all homes in the United States have air conditioners... and they consume roughly 6% of all the electricity produced in the United States, costing homeowners about $29 billion annually. 

There are a number of ways to work with your current system to reduce energy usage, including:

However, getting the most cooling for your dollar starts with selecting a new central air conditioner for your home. And, more specifically, it means understanding what a SEER rating is and how to use it to select the highest efficiency model that makes sense for your budget.

What is SEER?

SEER is an acronym for Seasonal Energy Efficiency Ratio. Much like MPG (miles per gallon) for your car, it’s a standardized rating number used to compare the energy efficiencies of different central air conditioners and heat pump systems. Like miles per gallon, the higher the SEER number, the more efficient the system.

SEER is calculated using the total amount of cooling provided during the cooling season, divided by the total electrical input during the cooling season. 

Where do I find a unit’s SEER number?

Most HVAC manufacturers will list each unit’s approved SEER rating online. Your local dealer may have brochures or spec sheets on the products they offer, typically with SEER ratings included. And, every air conditioner made in the U.S. will carry a yellow EnerygGuide label with the unit’s SEER rating. 

Minimum SEER ratings

The Department of Energy has established minimum efficiency standards for central air conditioners, currently divided into three regions across the U.S. 

- 13 SEER is the minimum in the North region

- 14 SEER is the minimum in the South and Southwest regions

As reported by the DOE, today's best air conditioners use 30% to 50% less energy than models from the mid-1970s to produce the same amount of cooling. A newer, more efficient model might save you 20% to 40% of your cooling energy costs even when compared to a 10-year-old unit.

Maximum SEER ratings

Because HVAC manufacturers are always developing newer and better technologies, “maximum” ratings are always changing. Generally speaking, any air-source central air conditioner rated at 18 SEER and above should be considered a high-efficiency model, with some rated as high as 21 SEER. Higher efficiency models that meet specific DOE standards can be easily identified by the ENERGY STAR® logo as well.

Turn to the Experts

Carrier offers a wide selection of air conditioners and heat pumps, from minimum efficiency models to higher performing ENERGY STAR models with a SEER rating as high as 20, to offer you reliable and efficient home comfort.