If you’re shopping for a new air conditioner or heat pump, you’ll come across the Seasonal Energy Efficiency Ratio (SEER). SEER is a tool that homeowners can use to compare the ACs and heat pumps that they’re considering. Let’s explore what you should understand about this rating system.
SEER measures how efficient a cooling system is over an average cooling season. In other words, it reflects how much a cooling system is going to cost you to run over a typical summer. A SEER 20 AC will be cheaper to operate each year than a SEER 14 AC.
ACs and heat pumps provide cooling by transferring heat energy. In the U.S., the industry measures this heat energy as British Thermal Units (BTUs). The industry calculates SEER by dividing the BTUs of heat removed by the total amount of energy required in watt-hours.
Most consumers can simply use the SEER rating at face value. If you want to dig a little deeper, you can use SEER to determine your costs. A 24,000 BTU/hour AC with a SEER 13 rating will consume 1,846 watts on average. To get the wattage, divide the BTU/h by the SEER value. If your electricity price is $0.20/kilowatt-hour (kWh), it would cost you $369.20.
That amount reflects an average cooling season, which is eight hours times 125 days or 1,000 hours. You could also calculate your costs more accurately based on the cooling needs for your home and area.
In the 1970s, the average SEER rating was just 6. In 2024, the average is 16, and the highest for a central AC system is 25. These achievements have largely been possible through innovations in condenser technology. The condenser pump is what pressurizes the refrigerant. The condenser coil is how heat energy transfers from the system to the ambient air. Modern condenser coils are much larger. Modern capacitors are more refined, and the condenser pumps are more sophisticated. The most efficient systems tend to have variable-speed condenser motors as well. These motors don’t have to run full throttle all the time.
Seasonal Energy Efficiency Ratio 2 (SEER2) is a revision of the original SEER rating. ASHRAE developed it with the DOE, and it went into effect in 2023. The main difference is in how labs must test the units. They now account for the static air pressure of the air handler.
The DOE will eventually deprecate the SEER rating. In the meantime, all ACs, heat pumps and ductless mini-splits made in 2023 and beyond must have both. Consumers can compare SEER to SEER and SEER2 to SEER2 but not SEER to SEER2.
The current minimum SEER and SEER2 ratings set by the DOE went into effect January 1, 2023. For the purposes of energy efficiency ratings, the DOE organizes the U.S. into three regions: North, Southeast and Southwest. The minimum SEER in the North is 14, and the minimum SEER2 is 13.4. The minimum SEER in the Southeast and Southwest is 15, and the minimum SEER2 is 14.3.
The federal government requires all appliance manufacturers to provide energy efficiency information. Manufacturers provide these details via an EnergyGuide label. This a large, yellow sticker that displays SEER, SEER2 and other information related to energy usage. You can usually find this information on the manufacturer website as well. You can also find it on the website for the Environmental Protection Agency (EPA) if the product is Energy Star certified.
While there’s marketing that suggests otherwise, an AC with a higher SEER rating won’t make your home more comfortable. What will dictate your comfort is the size of the AC. You need an AC that provides a certain cooling capacity based on your home’s square footage and ceiling heights. An AC that’s too small or too big won’t be as comfortable.
The ideal SEER is a matter of perspective. If the goal is choosing the most eco-friendly AC, then the higher the better. From a cost perspective, the DOE minimum SEER for your region is a solid choice for the average homeowner. To determine whether you should spend more, you need to calculate how long it will take to recoup the added cost. The tax credit, a rebate and the lower operating costs will help recoup it. On the other hand, ACs with very high SEER ratings are often relatively expensive to repair due to the cost of the parts. This is a discussion you should have with your HVAC technician.
Eagles HVAC Services installs, maintains and repairs ACs and heat pumps throughout Aldie and the surrounding areas. We also specialize in gas and electric furnaces and boilers and ductless mini-splits. Our team installs ductwork, HVAC zoning, dehumidifiers and humidifiers as well. We also install both tank and tankless water heaters. Call us today or contact us online to learn more about these products and services or to schedule an appointment.