HVAC 101: How can I use EER and SEER?

When it’s time for an HVAC replacement, there’s a lot of options to consider. To a non-expert, choosing a new unit can be an overwhelming decision, which is why the industry created the EER and SEER ratings systems. Both ratings are useful, but are best used in the right context when making heating and air decisions.

The EER

The EER, or Energy Efficiency Rating, has been around since 1975 as a way for HVAC technicians and engineers to compare the cooling efficiency of systems of all different ages and from all different brands. The EER is most notably different from the SEER because it is based off of a constant scenario. The number rating a system will receive from the EER is always based on how it would perform when the temperature outside is 95 degrees, while keeping the inside of the house at 85 degrees, with a 50% humidity.

The best time to use an EER rating to make an a/c decision is when looking at a small window unit or comparing units of different brands to one another. It’s important to note that most of the time the EER will be hard to find on your unit and is typically used much less frequently than the SEER number.

The SEER

SEER is a newer method of measuring system efficiency, and is great because it takes into account the way your A/C will behave during prime cooling season. Seasonal Energy Efficiency Ratings are determined by calculating the average cooling output of your unit over an entire cooling season, and dividing that by the energy consumed to do the work. It’s a much more tailored approach to efficiency that gives a better sense of how your unit will perform during its hardest working months.

If you are replacing an old unit, you might want to see what the current SEER rating is. Units from before 2006 will typically be below the new standard of a 13 SEER, and have probably been costing you much more in energy costs than you should need to pay. In fact, if your current a/c unit is from the 1970s, with a SEER of 6, a new system at the base standard of SEER 13 could cut your energy bills in half!

The important thing to remember when looking at EER and SEER ratings is to compare with context. Always compare SEER to SEER numbers and EER to EER numbers. If you can’t find the label on your unit, just ask your technician! At Middleton Heat & Air, our expert techs are trained to help you find the best unit, at the best efficiency, for your home and climate. We’ve been serving Central Arkansas for over 40 years, so we know a thing or two about combating Arkansas Heat! Contact us today to learn more about how we can save you money, and keep you cool! 1-800-404-0371