A2L Refrigerants in Air Conditioning Applications
As the refrigerant transition accelerates, lower-GWP A2L refrigerants will become increasingly viable alternatives to high-GWP HFCs in the air conditioning sector.
As the refrigerant transition accelerates, lower-GWP A2L refrigerants will become increasingly viable alternatives to high-GWP HFCs in the air conditioning sector.
A2L refrigerants are a new and relatively unknown commodity in the U.S. AC sectors. With the stage set for wider A2L adoption in the coming years, many stakeholders have a variety of inquiries that need to be addressed. Copeland experts are setting out to explain the drivers behind the emergence of A2L refrigerants and discuss their safe application as a mildly flammable refrigerant.
In a new series, A2L Fundamentals, we will provide an overview of the regulatory landscape that’s paving the way for A2L adoption. As the hydrofluorocarbon (HFC) refrigerant phasedown progresses rapidly around the globe and in the U.S., the retail supply chain is transitioning to the next generation of refrigerant alternatives with lower global warming potential (GWP). A2L refrigerants are among the leading emerging candidates capable of achieving the necessary GWP reductions.
HVACR service technicians find themselves at the forefront of the refrigerant transition in the air conditioning industry. A2Ls have been approved by the Environmental Protection Agency’s (EPA) Significant New Alternatives Policy (SNAP) Rules 23 and 25 list several mildly flammable (A2L) refrigerants, including R-454B and R-32, as acceptable, subject to use conditions in new residential and light commercial air conditioners and heat pumps.
From a service perspective, the transition from existing refrigerants to A2Ls will not require a fundamental shift in the way you conduct business. However, it will require more rigorous attention to basic servicing fundamentals. Existing recommended best practices for A1 refrigerants will apply — with the addition of a few special considerations, new equipment and A2L-rated tools. Take a moment to review Copeland's back to basics guide for technicians who service mildly flammable refrigerants.
A2L Refrigerants FAQs
A2L encompasses a class of refrigerants that have lower toxicity and flammability than A2 or A3 refrigerants, as listed by the American Society of Heating, Refrigeration, and Air Conditioning Engineers (ASHRAE) in ASHRAE Standard 34 (2019).
Compared to “highly flammable” A3 refrigerants, A2Ls are less flammable, as measured by three flammability criteria: 1) Higher lower flammability limit (LFL), meaning that it is less likely to form flammable concentrations; 2) Lower minimum ignition energy (MIE), meaning that it requires an open flame or strong electrical energy source to sustain an ignition; 3) Lower heat of combustion (HOC), meaning that it has a lower severity of ignition events.
It’s important to remember that individual A2L refrigerants will have varying degrees of flammability or global warming potential (GWP).
As of June 2021, A2Ls have been approved by the Environmental Protection Agency’s (EPA) Significant New Alternatives Policy (SNAP) Rule 23 for use in residential AC applications. Although the EPA has not yet approved A2Ls for use in commercial refrigeration, industry stakeholders expect further guidance and SNAP approvals in the near future. A2Ls have proved to be operationally safe and effective for commercial refrigeration applications in Europe and other regions.
A2L refrigerants offer unique thermodynamic properties and excellent performance characteristics that are similar to or better than common A1 HFC refrigerants such as R-404A or R-448A. Because performance characteristics will vary depending on the application, it’s important to check with Emerson’s application engineers to determine the optimal A2L refrigerant for your specific application.
