The energy efficiency of an AC unit is obviously important since this will be the primary factor in determining how much you spend to cool your home. When comparing the energy efficiency of different AC units, the thing you need to focus on is the SEER rating. SEER stands for Seasonal Energy Efficiency Ratio, and this rating can be used to estimate how annual cooling costs for different AC units. To make this easier, let’s take a look at what SEER ratings mean and how to choose which rating is best.
An Introduction to SEER Ratings
Comparing the energy efficiency of central air conditioners, heat pumps and other cooling equipment is more difficult than comparing the efficiency of different furnaces. The efficiency of a furnace should never change as long as the system is working properly. However, the efficiency of air conditioners can change quite a bit. This is because the system may use more or less energy on any given day depending on the outside temperature and humidity level.
The SEER rating system eliminates this problem by looking at the unit’s average efficiency over one cooling season. To calculate SEER, you need to know how many BTUs (British Thermal Units) of cooling the unit produces and how many watt-hours of electricity it consumes. Divide the BTUs by the watt-hours, and this gives you the SEER rating.
Federal Minimum Efficiency Standards
The US Department of Energy has minimum efficiency standards that all new central ACs and other cooling equipment must meet. As of writing, the minimum required in Virginia and the rest of the northern US is 13 SEER. For the southern half of the country, the minimum is 14 SEER. Beginning in January 2023, the minimums will increase to 14 SEER and 15 SEER respectively.
It is important to note that the minimum standard was only 10 SEER up until 2006, and there are many homes that still use 10 SEER units. If you still have a 10 SEER unit, even upgrading to the most basic unit available will result in a major decrease in your yearly cooling costs. Each increasing SEER number is approximately 7% more efficient than the previous number. This means that upgrading from a 10 SEER to a 13 SEER unit will lower your energy costs by at least 21%. Most likely it will be even higher than 21% as the energy efficiency of ACs tends to decrease quite a bit with age.
How to Decide Which SEER Rating Is Best
Most central air conditioners are between 14 and 22 SEER. You can find units up to 27 or 28 SEER, but these are typically not worth the high purchase price as they will still end up costing you more in the long run. As you might expect, the purchase price tends to increase with the SEER rating.
If you’re looking for a ductless mini-split instead of a central AC, you will find that mini-splits are much more efficient. The SEER rating for most mini-splits will be in the lower to mid-20s, and many units are well into the 30s. On the other hand, the efficiency of heat pumps and central ACs is almost identical.
The easiest way to decide which SEER is best is to look at the estimated lifetime energy costs for units with different SEER ratings. You can then compare this to how much each unit costs. This enables you to see whether the estimated energy savings from a higher efficiency unit is enough to offset the increased purchase price. If the energy savings don’t outweigh the higher initial cost, then you’re probably best going with the lower-rated unit unless money is no object.
For most people, a SEER rating somewhere in the lower to mid-range is typically best. That being said, if energy efficiency is your primary concern and you don’t mind paying quite a bit more for a higher-rated unit, then you should definitely go with the highest SEER you can get.
Chesapeake’s AC Installation Experts
Simmons Heating & Cooling has been helping people in Chesapeake and the surrounding areas meet their home comfort needs for nearly 60 years. We are a Lennox Premier Dealer, and we also carry a wide selection of central ACs, mini-splits, furnaces and other HVAC equipment from other top brands like American Standard and Mitsubishi. We offer flexible financing options for new equipment installations with approved credit. Our NATE-certified technicians are also experts in HVAC maintenance and repairs and can work on any make and model. For more information on your AC installation options, give us a call today.