Tips & Resources

M1 Efficiency Regulations Q&A

Effective January 1, 2023, energy efficiency metrics for residential air conditioners and heat pumps are expressed in terms of Seasonal Energy Efficiency Ratio (SEER2), Energy Efficiency Ratio (EER2), and Heating Seasonal Performance Factor (HSPF2)

Improving energy efficiency has become a top priority through the years. More efficiency has proven to save money, reduce emissions, protect the environment, and introduce several health benefits to the community. Although these new standards were enacted in 2023, many homeowners still do not understand what these regulations mean.

At Rheem Pro Partner, we proudly provide Colorado with safe and efficient HVAC systems. Here is a FAQ page answering some of your most pressing questions about what the M1 efficiency regulations mean for your HVAC system.


What is M1 Efficiency?

In 2023, The U.S. Department of Energy (DOE) established a minimum efficiency standard for air conditioning and heat pump equipment in the United States. As a result, HVAC manufacturers were required to shift their production activity to align with DOE standards.

How is M1 Efficiency affecting homeowners? 

The new standard has improved HVAC efficiency and safety for homeowners. Due to the new regulation, homeowners have more efficient comfort systems that are more intuitive. As a result, homeowners will experience better comfort in a more environmentally friendly environment.

Why are HVAC systems more expensive now?

In addition to improved comfort, homeowners are experiencing a rise in the cost of HVAC systems. This is due to the hundreds of hours invested in product development, issues with supply chains, component/material shortages, and government regulations.

What changes has the M1 Efficiency Introduced? 

The M1 Efficiency introduced several changes. The core change was that the M1 moved away from previous efficiency metrics, such as SEER, EER, and HSPF. The new metrics that were put in place include SEER2, EER2, and HSPF2. Previous metrics have been discontinued.

These new standards provide an entirely different way of calculating energy efficiency and are more representative of the installation in today’s homes. Minimum efficiency standards have increased roughly 7-10% or 1 SEER compared to the traditional metrics.

What does SEER2 mean?

SEER2 stands for Seasonal Energy Efficiency Ratio 2. SEER2 is the total heat removed from the conditioned space during the annual cooling season. The current M1 testing procedure has increased HVAC systems’ external static pressure by a factor of four or five to align with the field conditions of installed equipment.

What requirements must all HVAC systems meet?

To meet the M1 efficiency requirement, all HVAC system components have been redesigned to remain compliant. More specifically, all air conditioning units and heat pump systems must be renovated to meet all standards as of January 1, 2023, regardless of whether they met previous SEER ratings.

Additionally, matching components such as furnaces and air handlers were redesigned to meet changes in the airflow setpoint. Depending on your region, additional field installation equipment, such as thermal expansion valves (TXVs), may be required.

How has Rheem adapted to the M1 Efficiency regulations?

At Rheem’s Pro Partner, we have ensured that residential equipment meets DOE M1 standards. Our enhancements in our residential lineup include:

  • Econet smart technology on more mid- and high-SEER2 systems
  • Bluetooth installer setup
  • Multi-stage heating and cooling on more systems
  • More inverter-driven systems
  • Smaller footprint for some outdoor units

Understanding HVAC Regulations with Rheem Pro Partner

Since the Department of Energy established the new M1 efficiency regulations in 2023, Rheem Pro Partner has embraced the change to deliver innovative technology, such as coil and compressor technology, electronics, and connected solutions.

All HVAC systems effectively meet DOE M1 standards. Additionally, all Rheem Pro Partners and dealers have undergone extensive product and technical training on all residential heating and cooling systems to deliver the best products to families. Are you ready to install your new M1 efficient HVAC system? Get started with a Certified Rheem Pro Partner today.