SEER2 FAQ
To help you see the savings light, we covered the SEER2 basics in “What’s a SEER2 rating?” Read on for a deeper dive into some frequently asked questions about SEER2.
What is SEER?
SEER stands for Seasonal Energy Efficiency Ratio. It measures how efficiently an air conditioner or heat pump cools your home. The higher the number, the more efficient the system is.
Essentially, SEER2 ratings are your heating and air conditioning systems’ version of miles per gallon (MPG) or miles per gallon equivalent (MPGe).
What’s the difference between SEER and SEER2?
Since the SEER system started in 1992, there have been a lot of changes in the technology we use to heat and cool our homes. Plus, our understanding of how things like ductwork and external static pressure can affect efficiency has improved. That’s why the SEER2 standards are now in effect. The new standards more accurately measure system efficiency in real-world conditions.
The calculation is similar to SEER: it measures the cooling output over a season divided by the energy used. However, the testing procedures are stricter, so SEER2 ratings are typically lower than SEER for the same system — not because the system got less efficient, but because the new test is more accurate.
To go back to our car analogy, imagine you’re testing a gas-powered car’s fuel efficiency, but instead of smooth highway driving, you’re towing a boat or you’re stuck in stop-and-go traffic with a trunk full of kitty litter and six cases of water. Your mileage is going to suffer from the added exertion and weight — but it’s likely how you spend a lot of your time behind the wheel! SEER2 does something similar by simulating more realistic conditions for your home’s HVAC systems.
As of January 2024, all new heating, ventilation and air conditioning (HVAC) systems had to have a SEER2 rating. You may notice that new products may be marked with a SEER and SEER2 rating for a few years as manufacturers adopt the new standards.
The SEER2 rating is slightly lower than the original SEER. This accounts for energy leakage in air ducts. For example, a unit with a SEER of 15 will typically have a SEER2 of 14.3. The federal tax credit is determined based on the SEER2 rating. When combined with the new increase in minimum SEER ratings, the energy savings are significant.
Simply put, SEER2 is the total heat removed from a conditioned space during an annual cooling season. Visit SEER2.com for a more detailed dive into testing requirements and procedures.To calculate an air conditioner’s SEER2, for example, we add up all the cooling the system produces during a typical cooling season and divide it by the total electricity it uses during that same time.
How is SEER2 calculated?
Higher SEER2 means the system is more efficient, just like a car that gets more MPGs or MPGes saves you money on gas or electricity.
Just as you’d divide the number miles you drove by the amount of gasoline you put in a gas-powered car to determine your miles per gallon (MPG), SEER2 is calculated by dividing the cooling output of your unit by the watt-hours of energy it consumes.
For example, if your unit produces 10,000 BTUs of cooling power and consumes 1,000 watt-hours it would have a low SEER rating of 10.
What’s the difference between SEER2 and EER?
The efficiency of window air conditioners and portable air conditioning units is generally measured as EER rather than SEER2. SEER2 measures a system’s average efficiency over an entire cooling season, while EER measures efficiency under specific testing conditions. Smaller, single-room window units are less affected by environmental conditions (they don’t have ducts!) than central cooling systems, so EER is a better measure of efficiency for them.
What’s a good SEER2 rating?
As of 2024, the U.S. Department of Energy requires that central air conditioning systems in the seven-state Tennessee Valley region have a minimum SEER rating of 15 and a minimum SEER2 rating of 14.3. The higher the SEER2 number, the more efficient your unit will be. The more efficient your unit, the more money you’ll save over the system’s lifespan.
Typically, ENERGY STAR-certified units have a SEER2 rating of 15.2 (16 SEER) or higher.
Where can I find the SEER2 rating of my unit?
Look for a bright yellow and black EnergyGuide label. If your unit is older, the label may have faded, but it should be there. Not all appliances have this sticker, but most heating and cooling units do. The SEER and SEER2 ratings will be clearly labeled.
If you don’t see the sticker, you can do an online search using the manufacturer, model number and unit size to determine your system’s rating.
What makes an air conditioner high efficiency?
It’s all about the compressor and condenser. Air conditioners with SEER2 ratings between 14 and 16 use the same basic technology. AC units with a SEER2 rating of 17 and higher use a different type of compressor and condenser fan to achieve maximum efficiency.
What products are affected by SEER2 regulations?
- Air conditioner condensing units
- Heat pumps
- Single packaged units
- Evaporator coils
- Gas furnaces
Are there rebates available on SEER2 air conditioning units and heat pumps?
Yes! You can find rebates from TVA EnergyRight here. Federal tax credits are also available.
