Jul 17 2018 russelladmin
Air Conditioner Efficiency: What Are EER and SEER?

Russell's Heating and Air ConditioningWe’re in the middle of the time of the year when homeowners are often looking into replacing their air conditioning systems. Having a new air conditioning installation in Palm Desert, CA before the big heat of summer strikes is a good idea. If you have any suspicions that your current AC won’t make it through the coming season, make an appointment with our team to look over the air conditioner and offer you recommendations about whether to replace it or not… and what kind of system to replace it with.

The Question of Efficiency

When looking into the installation of a new air conditioning system, one of the key things to investigate is energy efficiency. Newer air conditioners have higher energy-efficiency ratings than ever before, and requirements of the U.S. Department of Energy’s ENERGY STAR program have increased since 2015.

However, just because one AC model has a higher efficiency rating than another doesn’t automatically mean it will save you more money. It’s vital to have professionals assist you with locating a system that not only has the best efficiency for your needs, but also is the right size for your home’s cooling requirements.

With this in mind, let’s take a close look at the two efficiency ratings you find on air conditioners—EER and SEER—and what makes them different.

EER = Energy Efficiency Ratio

The energy efficiency ratio (EER) is the basic way of measuring how much electrical energy an air conditioner uses to provide cooling. The ratio is the amount of heat removed from the air (measured as BTUs, British Thermal Units) to the amount of electricity consumed (measured in watt-hours). The test to determine EER is done under a set of specific conditions: outdoor temperatures of 95°F, indoor temperatures of 80°F, and 50% relative humidity levels. The higher the resulting number, the less electricity the system uses to produce cooling. The current EER requirement for ENERGY STAR certification is 12.5 or greater for split systems.

SEER = Seasonal Energy Efficiency Ratio

If SEER and EER look like they are almost the same thing, it’s no accident. SEER is the same ratio of heat removed from the air to electricity consumed, and the higher SEER, the more efficient the system. So what difference does that “S” make? It’s the difference in how the measurements are made. SEER is determined over an entire season and a variety of conditions, rather than a single spot test under one set of conditions. Testing for SEER uses indoor and outdoor temperatures from as low as 65°F to as high as 105°F, with an equally wide range of relative humidity levels. This gives a sense of how efficiency an AC will perform over an entire summer season. The current SEER requirement for ENERGY STAR certification is 15 or greater for split systems.

Which Rating Is More Important?

They’re both important, although you’ll probably lean a bit more on SEER since it allows an easier calculation of what you might save over a whole season of cooling. As long as you have a professional HVAC technician to assist you with your new air conditioning installation, you shouldn’t have a difficult time finding the SEER/EER combination that will work best for your home and deliver genuine energy savings this summer and many summers to come.

Russell’s Heating & Air Conditioning has served the Desert Communities and the Inland Empire since 1980.

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