When it comes to choosing a new air conditioner or heat pump, it’s easy to get overwhelmed by all the specs. But one acronym you shouldn’t overlook is SEER. This simple number plays a huge role in how much you’ll spend to stay cool — and how energy-efficient your system will be for years to come.

At United Air Temp, we bring decades of experience and smart cooling solutions to help you understand SEER ratings and choose systems that save energy, cut costs, and keep you comfortable.

Understanding the SEER Rating System

SEER stands for Seasonal Energy Efficiency Ratio — a key number that shows how efficiently your AC or heat pump cools over a full season.

The higher the SEER, the more efficient the system — leading to less energy use, smaller bills, and a greener way to stay cool.

What Is SEER2?

As of 2023, HVAC systems undergo advanced testing and are rated by SEER2. SEER2 is the total heat removed from the conditioned space during an annual cooling season.

New M1 testing procedures increase external static pressure on the system by a factor of 5 to more accurately reflect field conditions of installed equipment.

What’s a Good SEER2 Rating in 2025?

As of 2025, most modern air conditioners and heat pumps range from 14 to 26 SEER2, with some premium systems even higher.

Here’s a breakdown of what you need to know about SEER2 ratings:

• Entry-level systems rated 15 to 17 SEER2 meet the minimum efficiency requirements in most U.S. regions and are often more affordable upfront.
• Mid-range systems rated 18 to 20 SEER2 are a good balance of energy savings and cost, especially if you live in a warm climate.
• High-efficiency models rated 21 to 26 SEER2 or more are best for hot, humid climates or homeowners looking to maximize long-term savings and reduce environmental impact.

In Washington, D.C., and Northern Virginia, federal regulations require a minimum SEER2 rating of 15 for central ACs — part of a regional effort to match efficiency standards with local climate demands.

How SEER Ratings Impact Your Energy Bills

Choosing a higher-SEER system can lead to significant energy savings over time. While high-efficiency units usually cost more upfront, they often pay for themselves through lower monthly utility bills.

If your system is over 10 years old, it’s likely nowhere close to modern energy efficiency standards. According to the U.S. Department of Energy, upgrading from a 9 SEER2 to a 15 SEER2 system can reduce cooling costs by up to 35%.

Keep in mind that SEER ratings come from lab tests in ideal conditions. Real-world performance can vary based on ductwork, insulation, and climate. Still, SEER2 is a great way to compare efficiency — and when used often, high-SEER2 systems can offer a strong return on investment.

SEER2 vs. Other Efficiency Metrics – EER2 & HSPF2

SEER2 isn’t the only number that matters. EER2 and HSPF2 also offer valuable insight depending on your system and how you use it throughout the year.

Here’s when to use each:

• SEER2 (seasonal energy efficiency ratio) is ideal for comparing cooling efficiency for central ACs and heat pumps. It measures how efficiently a system cools over an entire season, including start-ups and shut-offs — giving a realistic look at overall energy use.
• EER2 (energy efficiency ratio) measures how a system performs at a steady 95°F. It’s helpful in very hot climates or for comparing window units.
• HSPF2 (heating seasonal performance factor) applies to heat pumps and shows how efficiently they heat your home over the winter — useful if your system handles both heating and cooling.

If you’re in a mixed climate like Washington, D.C. and Northern Virginia, it’s smart to consider both SEER2 for cooling and HSPF2 for heating.

How To Choose the Right SEER Rating for Your Home

Finding the right SEER rating isn’t just about picking the highest number — it’s about finding the right balance between cost, comfort, and efficiency for your home.

Here are a few key things to consider:

• Budget: Higher-SEER systems cost more upfront but can save you money over time.
• Climate: Hotter areas benefit more from high-SEER systems due to heavier AC use.
• Usage: If your system runs often, investing in higher efficiency makes more sense.
• Comfort vs. cost: SEER2 16 to 18 often strikes a good balance without the premium price tag.
• Ask your installer: Get their input on what makes sense for your home, including potential savings, ductwork compatibility, and any rebates.

Request AC Replacement From UAT

United Air Temp has delivered trusted HVAC solutions since 1931. We’re here to help you understand SEER2 ratings and make smart choices for energy-efficient air conditioning in your D.C. or NOVA home.

Our technicians complete over 40 hours of training each year, and we’re committed to treating every customer like a lifelong one.

Contact us today to find and install the right AC for your Washington, D.C. or Northern Virginia, home and experience service you can count on.