Since cooling systems use a good deal of energy, the U.S. Department of Energy (DOE) requires that manufacturers test them to determine their air conditioner ratings for energy consumption. The DOE sets minimum standards for central systems and portable units, and the process by which their ratings are determined is similar. The SEER (seasonal energy efficiency ratio) and EER (energy efficiency ratio) both indicate air conditioning efficiency, but the SEER only applies to central systems. Both portable and central systems carry EER ratings. When looking at new central systems, it’s just as important to understand the EER as it is the SEER to understand system efficiency.
Engineers find the SEER rating by running a cooling system for an extended period and measuring its energy use to cool a space to 80 degrees F when the outdoor air is a constant 82 degrees. Testing for the EER rating involves turning the outdoor temperature up to 95 degrees, which is an important aspect of home cooling since summer temperatures frequently reach into the 90s. A high EER rating indicates the system copes well with hotter weather.
The DOE raised the minimum central air conditioner ratings to 14 in 2015, which means that such a system used 10 percent less electricity than one with a SEER rating of 13 under testing conditions. Replacing an older unit whose efficiency rating is even lower is likely to save even more energy, since cooling systems tend to lose efficiency as they age. You may need to ask your HVAC contractor to identify the EER rating for you on the systems you consider, since it’s usually not readily apparent. The SEER rating is always prominently displayed on the packaging and equipment. A system with a high EER rating may have upgraded features that also raise the SEER. Understanding air conditioner ratings is vital when selecting a new system. To learn more, contact Russell's Heating & Cooling, providing trusted HVAC services for the Hampton Roads area of Southeastern Virginia. Our goal is to help educate our customers in Chesapeake, Virginia and surrounding areas about energy and home comfort issues (specific to HVAC systems). For more information about air conditioner ratings and other HVAC topics, download our free Home Comfort Guide or call us at 757-750-1831. Credit/Copyright Attribution: “Name of Artist/Shutterstock”