HVAC Basics: Energy-Efficient HVAC Systems

By Anne Fonda with expert review by Kimberly Sexton, Senior Systems Engineer

For years, the ENERGY STAR® program has helped homeowners choose products that can help save energy, and therefore save money on energy bills. To qualify for ENERGY STAR certification, products must be independently tested and proven to save energy over standard models. And since about 50% of the average homeowner's energy bills result directly from heating and cooling the home, it makes financial sense to look for an ENERGY STAR-certified HVAC system.

Update on energy-efficient air conditioners

As of July 15, 2025, ENERGY STAR stopped certifying central air conditioners (CACs). Not because they don’t support energy-efficient AC systems, but because they do. They just think heat pumps are more energy efficient at cooling AND heating.

The Environmental Protection Agency (EPA), which oversees the ENERGY STAR program, concluded that in almost all parts of the U.S., electric heat pumps are a more energy-efficient, sustainable alternative for both heating and cooling.

ENERGY STAR heat pumps

ENERGY STAR-qualified heat pumps have higher Seasonal Energy Efficiency Ratio (SEER2) and Heating Seasonal Performance Factor (HSPF2) ratings, making them more than 15% more efficient than standard models.

As of 2026, to be ENERGY STAR-certified, a heat pump must meet the following product criteria.

≥ 7.8 HSPF2/ ≥15.2 SEER2/ ≥11.0 EER2 for split systems
≥ 7.2 HSPF2 ≥15.2 SEER2/ ≥10.0 EER2 for single package equipment, including gas/electric package units.

An energy-efficient heat pump can both heat and cool your home.

ENERGY STAR furnaces

ENERGY STAR-qualified furnaces have higher Annual Fuel Utilization Efficiency (AFUE) ratings and higher efficiency blower motors, making certified gas furnaces, on average, more than 10% more efficient than standard models.

As of 2026, to be ENERGY STAR-certified, a gas furnace must meet the following product criteria.

AFUE Rating of 90% or higher for U.S. South gas furnaces

AFUE Rating of 95% AFUE or higher for U.S. North gas furnaces

High-efficiency furnaces are well-suited for homes with colder winters. They can also be paired with a heat pump in a dual-fuel system.

Increase comfort and save energy by installing an energy-efficient heating and cooling system

First, do your homework and learn about the pros and cons of various systems so you can make an informed decision. More energy-efficient AC units, furnaces, and heat pumps will cost more upfront, but can help you increase comfort and save money on your energy bills for the long term.
Next, get 3 quotes from trusted HVAC companies near you.
Make sure they perform a load calculation before recommending a system size.
Choose an HVAC contractor to install your new system. Other than correct system sizing, proper installation is the most important factor in your new system’s performance and your long-term comfort.

Maximize energy savings with a smart thermostat

If you’re investing in an energy-efficient HVAC system, you can help ensure you save the most energy by installing a smart thermostat at the same time. When you take advantage of the personalized programming and geofencing capabilities, your smart thermostat will raise or lower the temperature when you’re not home to save energy. You can also use the Home App to control your HVAC system from anywhere, at anytime, to maximize comfort and energy savings.

Anne Fonda, Content Writer

A Content Writer with Trane Technologies, Anne Fonda researches topics and writes for Trane® and associated residential HVAC brands. She works in collaboration with Trane Technologies subject matter experts, offering easy-to-understand, informative content on complex topics. Her goal is to help consumers make informed decisions on the products and services they need.

She has written for HVAC and other service provider websites for over 16 years. Before transitioning to web content writing, Anne had a 14-year stint as an award-winning journalist. She graduated cum laude from the University of Missouri-Columbia School of Journalism.

When she’s not working, Anne enjoys playing word games, reading, gardening, spending time with family, and visiting gardens and museums.