Q: My 15-year-old air conditioning unit finally gave up, so I’m in the process of shopping for a new one. I’ve heard that SEER ratings are an important consideration when choosing a new model, but the numbers are confusing. What is SEER rating anyway, and how can it help me get the best air conditioner for my money?
A: An air conditioner is a big-ticket item, so you’re doing the smart thing by finding out all you can before you write that check. The Seasonal Energy Efficiency Ratio (SEER) relates to how much energy¡ªand money¡ªan AC unit will use over the course of 1 year. The United States Department of Energy (DOE) requires all new air conditioning units to meet minimum efficiency identified by these SEER ratings. And you’ll find many options that go above and beyond those minimums, as manufacturers have made significant advancements in technology and efficiency since your old AC unit was produced.
In short, the SEER rating ¡°lets homeowners compare one system to the next and understand which is more efficient,¡± says Tim Brizendine, Director of Product Management at Lennox.
To get a better understanding of SEER definition ratings and why they matter, keep reading; we’ll explain what the numbers mean and how you can make use of that information when choosing your new air conditioning unit.
When I replaced my own AC unit a couple of years back, I was overwhelmed by all the jargon, but digging into SEER ratings really helped me make sense of what I was paying for. The key thing to know is that SEER stands for Seasonal Energy Efficiency Ratio, which measures how efficiently an air conditioner converts electricity into cooling power over a typical cooling season. Think of it like the gas mileage for your car¡ªthe higher the number, the less energy it takes to get the job done. For example, the DOE notes that modern units can achieve SEER ratings up to 25, a huge leap from the 6 or 7 ratings common in older models from the 1990s. To put that in perspective, upgrading from a SEER 10 to a SEER 16 unit could cut your cooling costs by about 40%, depending on your home’s size and local electricity rates. I found it super helpful to use an online SEER calculator to estimate savings specific to my house¡ªit’s worth taking 10 minutes to plug in your numbers.
The Higher the SEER, the More Efficient the Unit¡ªand the More You’ll Save on Utility Bills
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¡°As the number increases, we get a higher efficiency system, which means lower utility bills for the homeowner,¡± Brizendine explains.
What does SEER mean in practical terms? How much you’ll actually save on your utility bills depends on the size (and insulation factor) of your house, how much you pay per kilowatt hour for electricity, the SEER rating of the unit, and what it’s currently costing you to cool your home.
You can estimate the savings a new appliance with an improved SEER rating would bring you using one of many online SEER rating calculators, or you can download a spreadsheet calculator from Energy.gov.
Air conditioners on the market today range from 13 to 25 SEER. The rating itself is determined through calculations of a unit’s average performance¡ªthe amount of cooling an AC system puts out per the units of energy it uses to do so¡ªbut it’s a pretty simple concept. The less energy used, the higher the SEER rating.
You can use SEER ratings to roughly estimate annual cooling costs. Multiply the cooling capacity (BTUs) at 95 degrees Fahrenheit by the current electrical multiplier (.132) and divide that by the SEER rating of your unit. That will tell you your cost of operation.
The science behind SEER is straightforward but fascinating. It’s calculated by dividing the total cooling output (in BTUs) over a season by the total energy input (in watt-hours). This gives you a ratio that reflects real-world performance, not just lab conditions, which is why it’s so useful. For instance, when I was shopping, I learned that a 3-ton AC unit with a SEER of 16 might cost around $600-$800 a year to run in a hot climate like Texas, compared to $900-$1,200 for a SEER 10 unit, based on average electricity rates of about 14 cents per kWh. If you’re in a milder climate, the savings might be less dramatic, but they still add up. A pro tip: check your insulation and seal any air leaks before installing a new unit. I noticed a big difference in my cooling costs after adding some weatherstripping to my windows, which made my new high-SEER unit even more effective.
The Average Central AC Unit Sold Today Has a SEER Rating Between 15 and 18
In 2006, the DOE began requiring all newly installed central AC units to have a minimum SEER rating of 13. Units manufactured in previous years were often energy hogs¡ªmany with AC SEER ratings as low as 6.
Higher-efficiency models are available that come with numbers in the mid-20s.
Choosing a 17 SEER unit over a 15 SEER unit could add $1,500 to $2,500 to the purchase price.
High efficiency comes at a price. ¡°Higher technology¡ªand higher-performing equipment¡ªoffers better temperature control and better comfort level,¡± Brizendine says, but the advanced technology that goes into producing AC units with higher SEER ratings also increases their cost.
Recognizing this, many air conditioning manufacturers¡ªLennox included¡ªproduce high-efficiency models alongside models in the minimum SEER range, and options at every level in between, ¡°to meet budget requirements for everybody,¡± Brizendine says.
It’s worth noting that the jump from older units to today’s standards is huge. My old unit was a SEER 8, and swapping it for a SEER 16 model felt like night and day¡ªnot just in energy bills but in how evenly it cooled my house. If you’re on a budget, a SEER 15 unit is a solid middle ground; it’s efficient without breaking the bank. For context, the Energy Star program certifies AC units at SEER 15 or above as energy-efficient, and many of these qualify for utility rebates. When I was shopping, I found that some local utilities offered $200-$500 rebates for units above SEER 16, which helped offset the upfront cost. Also, don’t sleep on maintenance¡ªkeeping your new unit’s filters clean and scheduling annual tune-ups can maintain that high efficiency for years.
As of 2015, the Minimum SEER Rating Allowed Is Determined by Where You Live
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In 2015, the minimum SEER was raised to 14 for people living in a number of states: Alabama, Arkansas, Arizona, California, Delaware, Florida, Georgia, Hawaii, Kentucky, Louisiana, Maryland, Mississippi, New Mexico, Nevada, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, and Virginia. Because these states have the hottest summer climates, the DOE determined that an increase in the minimum SEER would save energy.
Those not living in the states listed above may still have SEER 13 units installed. Northern states were not included in the increased minimum because where summers are cooler, homeowners use their air conditioners less often so there’s less need for high efficiency. Talk to your local HVAC contractor, though; just because you don’t live in the warmest states doesn’t mean you won’t benefit from a SEER rating higher than 13. Some regions not included in the above-mentioned states still get swelteringly hot in the summer, and oftentimes homeowners can benefit from a more efficient unit.
I live in one of those hotter states, and let me tell you, the SEER 14 minimum makes a difference when your AC is running nonstop in July. But even if you’re in a cooler state, don’t assume a lower SEER is always fine. For example, parts of the Midwest can hit 90¡ãF with high humidity, making a higher SEER unit worthwhile. The DOE estimates that raising the minimum SEER to 14 in those southern states saves about 7-10% on national cooling energy use annually. If you’re curious about your area, chat with an HVAC pro¡ªthey’ll know local climate patterns and can recommend a SEER rating that makes sense. I also learned that pairing a high-SEER unit with a programmable thermostat can boost savings by up to 15%, since you can dial back cooling when you’re not home.
The SEER Rating Isn’t the Only Factor to Consider When Choosing a New AC Unit
While energy efficiency is among the most important factors to assess when shopping for the best air conditioner, it’s not the only consideration. For example, you’ll also want to look at a unit’s power, which is expressed in British Thermal Units (BTUs). Consider the amount of noise produced by the air conditioning units you’re considering. Local municipalities may have restrictions, and you also want to be able to sleep without too much racket interrupting your beauty rest. Reliability is important, too, as is smart connectability and a unit’s warranty.
Besides SEER, I found BTUs and noise levels were huge factors when I picked my unit. A system that’s too small won’t cool your house properly, but one that’s too big will cycle on and off too often, wasting energy. A good HVAC contractor will do a Manual J calculation to size the unit right for your home. Noise-wise, some modern units are as quiet as 50 decibels¡ªthink library-level sound¡ªwhile older ones can hit 70 or more, like a vacuum cleaner. I also looked for a unit with smart features, like Wi-Fi connectivity, so I could control it from my phone. And don’t overlook the warranty¡ªmost high-SEER units come with 10-12 year warranties, but check the fine print for labor coverage. It saved me a headache when my unit needed a minor repair last year.
Final Thoughts
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Your HVAC contractor (installing a new AC unit is not a DIY project) will first determine the optimal size of the new AC unit. Once you know the size you’ll need, you can select your new AC unit, keeping in mind that the higher the SEER, the more efficient it will be. For most homeowners, opting for a unit with a SEER between 15 and 18 is a good choice because it’s a balance between the money you’ll spend for the unit and the amount you’ll save on utility costs.
Choosing the right SEER rating is about balancing upfront costs with long-term savings. When I got my new unit, I went with a SEER 16 model because it fit my budget and still cut my summer electric bills by about 30% compared to my old clunker. If you’re in a hot climate, going a bit higher, like SEER 18, might pay off faster¡ªsome studies suggest you can recoup the extra cost in 5-7 years through energy savings. Whatever you choose, make sure your contractor sizes the unit correctly and ask about local rebates or tax credits (like the federal credit for SEER 16+ split systems). It’s all about finding that sweet spot for your home and wallet.
FAQs About the SEER Rating
Still need more information to fully understand SEER ratings? Read on to get the answers to some commonly asked questions about this energy efficiency rating¡ªthey’ll help you decide whether it makes sense for you to invest in a highly rated air conditioning unit for your home.
Q. How much more efficient is a 20 SEER vs 14 SEER?
An air conditioning unit with a SEER rating of 20 is about 43 percent more efficient than a unit with a 14 SEER rating.
Q. Are high-SEER AC units worth it?
Whether a higher SEER AC unit is worth investing in depends on the climate in which it operates. If you live in a hot area and your unit runs practically nonstop 24/7, you’ll see a return on your investment fairly quickly. If you live in Duluth, however, spending extra money on a 20 SEER unit probably doesn’t make sense.
Q. What is the minimum allowable SEER rating for a federal tax credit?
The minimum SEER rating for federal tax credit is 16. This applies to split systems, where the condenser and compressor are housed separately from the evaporator coil, which is typical of most residential air conditioning systems.
One thing I’d add to the FAQ: if you’re eyeing that federal tax credit, make sure your unit is Energy Star-certified, as some SEER 16 units might not qualify otherwise. Also, if you’re debating between a SEER 14 and a SEER 20, think about how long you plan to stay in your home. A friend of mine went with a SEER 20 unit in Arizona and saw savings within three years because of the intense heat, but in cooler areas, it might take longer to break even. Always double-check with your HVAC contractor about local incentives¡ªthey can make a higher SEER unit more affordable than you’d expect.