When you’re thinking of purchasing a new air conditioner, the options can seem endless. With all the different brand names, sizes, and features available, settling on an AC can be difficult. Then you must contend with different SEER ratings for different air conditioners as well as the fact that the Department of Energy updated the rating system to SEER2 as of Jan. 1, 2023.
All this can make an already daunting process more confusing. At Coffman & Company, we want to share the knowledge you need to make the best investment possible. We’ll go over what SEER ratings are, why they’re important, and how to choose the best air conditioner for your Arvada, CO home.
The Seasonal Energy Efficiency Ratio (SEER)
Seasonal energy efficiency ratio (SEER) ratings express the efficiency of an air conditioning system. In order to do that, manufacturers measure the amount of cooling a system puts out during the course of a cooling season. They use British Thermal Units (BTUs) to measure this. Then, they divide that amount by the amount of electricity the system uses to put out that cool air. This is expressed in watt-hours, similar to how your electricity bill uses kilowatt-hours.
Theoretically, the only limit to how high of a SEER rating a system can get is the law of thermodynamics. That is, SEER ratings can only go so high because of how the physical world works. In practice, you’ll only see systems up to 22-24 SEER. The higher the rating, the less energy a system uses to cool your home.
On the other end of the spectrum, you can get as low as SEER 1, which is not efficient at all. Older air conditioners tended to hover between 10-15 SEER, but as technology has progressed, we’ve been able to push the efficiency of air conditioning systems.
That being said, the United States government does place minimums on the systems that manufacturers can sell. Legislation on these minimums was first passed in 1987 and went into effect in 1992, placing the minimum at 10. If a system was less than 10 SEER, it could not be sold in stores or by contractors. The government increased the minimum to 13 SEER in 2006 for any systems made after the year 2005.
The Department of Energy updated these standards in 2011 and set them to take effect beginning on January 1, 2015. However, the standards became a little more complicated. The DOE decided that, because the climate can differ so much from region to region, minimum SEER ratings needed to reflect that. They split the United States into several regions for rating purposes: Southwest, Southeast, and the rest of the country.
The Southwest region consisted of:
- Arizona
- California
- Nevada
- New Mexico
The Southeast region comprised:
- Alabama
- Arkansas
- Delaware
- Florida
- Georgia
- Hawaii
- Kentucky
- Louisiana
- Maryland
- Mississippi
- North Carolina
- Oklahoma
- South Carolina
- Tennessee
- Texas
- Virginia
In 2015, the minimum SEER rating for states in the Southwest and Southeast regions was 14. However, the rest of the United States (including Colorado, classified as a Northern state) had a different minimum: 13 SEER.
In 2023, the minimums were updated so that the Northern states had a minimum of 14 SEER2, while Southern ones had a minimum of 15 SEER2. (They’re still split into multiple other regions. As in 2006, some regions share minimums.) There was one caveat, though, which we’ll go over further down.
Keep in mind that these ratings apply only to conventional central air conditioning systems. You’ll still see SEER ratings on portable air conditioners and window units, but the previous (and current) minimums do not apply to them.
A Note About ENERGY STAR
Since 1992, the U.S. Environmental Protection Agency (EPA) has had an initiative known as ENERGY STAR that indicates appliances that are particularly energy efficient. Appliances approved for the ENERGY STAR label often have rebates or tax incentives available to help lessen the overall strain on our electricity grids. In 2006, the minimum rating for ENERGY STAR approval was 14.5 SEER. This was later updated to 16 SEER with the same caveat we mentioned above.
What About SEER2?
Along with changing the minimum SEER ratings in 2023, the U.S. Department of Energy (DOE) updated the SEER system to one called SEER2. To arrive at a SEER2 rating, manufacturers use an updated, more thorough testing procedure. You might see two ratings on air conditioners because of this, and as a rule of thumb, SEER ratings end up approximately 4.5% higher than SEER2 ones. For example, the ENERGY STAR requirements for 16 SEER are equivalent to those for 15.2 SEER2.
Cooling Loads and HVAC Capacities
SEER ratings give you an idea of how efficient an air conditioner is, but that doesn’t mean you can simply find the highest number on an AC, install the system, and expect reasonable results on your energy bills. Because of the wide range of structures out there, manufacturers make air conditioners in an array of capacities. You wouldn’t be able to use, say, an air conditioner intended for a small mobile home in a two-story house and get the same results.
Every place, from homes to offices to multipurpose trailers, has its own cooling load, which refers to the amount of cooling the structure needs to stay at a comfortable temperature. The weather and local climate factor into the cooling load, but there are many other variables, from the number of windows, type of said windows, and insulation in the building to occupants, heat sources, and so on.
HVAC technicians have several tools at their disposal to determine cooling loads, and one of the most common is called the Manual J calculation. By inputting a variety of factors into this calculation, your Coffman & Company technician can determine the amount of power — also in BTUs — that a home should need.
Once you have that number, you can narrow down your choices. You’ll still see a variety of brands, features, and SEER ratings, but you’ll be able to compare pricing and other considerations for just the size of system you need. This is more important than you might think. While it’s fairly obvious that a smaller system will struggle to cool down a larger home, oversized systems also cause problems by cooling your home too quickly. A larger system may sound like a good thing, but manufacturers design systems with specific cycle times in mind. If there is too short a cycle too many times, your AC won’t be able to regulate humidity in your home, and you might end up with hot and cold spots along with rising energy bills.
That’s where we can help. Coffman & Company can take care of your heating and cooling needs in Arvada. From central air conditioning maintenance to mini-split AC installation and heat pump repairs, we can do it all.
Call Coffman & Company for heating and cooling services today!
