Unraveling the Myths About HFOs and 'Natural' Refrigerants
In today’s refrigerant arena, we see hydrofluoroolefins (HFOs) in one corner and so-called “naturals” in the other. But in truth, these refrigerants have coexisted for some time, each serving specific needs of the HVACR industry. “Naturals”—that is, industrial gases including hydrocarbons, sulfur dioxide, ammonia, and carbon dioxide—once were broadly used, but their purpose and practicality in our world has diminished considerably due to HFO innovations. HFO refrigerants sit at the intersection of performance and sustainability, offering critical solutions for decarbonization, circularity, safety, and a business’s bottom line.
So-called 'natural' refrigerants will have a place alongside HFOs in today's HVACR industry. However, they cannot come close to matching the innovation of HFOs in terms of balancing the growing list of demands placed on refrigerants today.
By steering clear of the myths about HFOs and “naturals,” shop owners, contractors, and technicians can help customers make informed decisions when it comes to replacing systems at the end of life, as well as during new construction and installations. Here are what I consider the six biggest myths out there.
Myth 1: It comes down to a choice between a synthetic or natural solution.
All refrigerants—including those marketed as “naturals”—are synthetic. While it’s true that small amounts of ammonia or hydrocarbon molecules can be detected in our environment, refrigerant-grade products such as R-717 (ammonia), R-290 (propane) and other “naturals” are produced in industrial processes. Like HFOs their production requires energy and feedstock consumption, purification, packaging, warehousing, and transport. However, producing ammonia, for example, consumes a significant amount of energy and results in an enormous carbon footprint.
Myth 2: “Naturals” offer the best option for all applications.
Anyone in HVACR knows our industry is highly complex and consists of an untold number of applications. From home and mobile air conditioning to ice rinks and grocery superstores to refrigerated warehouses and transport, each application requires unique refrigerant properties. “Naturals” can meet some of the demand. But HFOs—born in chemistry and its adaptability—offer a greater ability to meet changing needs driven by evolutions in HVACR equipment and global sustainability requirements.
Myth 3: “Naturals” are futureproof.
Thankfully, nothing is future-proof, which means even the best solutions of today can get better for the demands of tomorrow. This is certainly true for HFOs. “Natural” refrigerants, however, were first adopted more than 100 years ago, then broadly abandoned due to HFO innovation as well as concerns over safety, energy consumption, and other factors. HFOs solve many of these issues and support a number of sustainability megatrends including decarbonization and circularity.
Myth 4: All flammable refrigerants are the same.
HFOs are reliable, have undergone rigorous regulatory approval processes, and are considered safe for their intended uses. Lower flammability A2L HFOs that are commercially available and OEM-approved are about four times less likely to form flammable concentrations during an accidental leak than highly flammable (A3) alternatives such as propane and butane. Commonly used HFO blends are also far more difficult to ignite. Moreover, hydrocarbon applications are far more restricted, due to allowable charge sizes and building codes.
Myth 5: The “naturalness” of “naturals” naturally supports circularity.
HFOs, unlike many “naturals,” are recovered, reclaimed, and reused—supporting maximum resource efficiency, minimal waste, and lower emissions. HFOs are critical to advancing circularity across the many industries they touch and create a path to decarbonization.
Myth 6: There is an endless supply of “natural” refrigerants.
The supply chain of HFO refrigerants is extremely strong and positioned to support the A2L transition around the world. More readily available than “naturals,” HFO refrigerants offer a secure and reliable supply chain for today’s many and various HVACR applications. In addition, there’s a much heartier pool of HFO technicians than “natural”-refrigerant technicians—a critical need, given current workforce shortages.
So-called “natural” refrigerants will have a place alongside HFOs in today's HVACR industry. However, they cannot come close to matching the innovation of HFOs in terms of balancing the growing list of demands—such as safety, performance, climate impact, and total cost of ownership—that are placed on refrigerants today and will continue to influence the future.
Charles “Dr. Chuck” Allgood, Technical Fellow with Chemours holds a PhD in chemistry, has more than 30 years of experience in the HVACR industry, and is a respected speaker at many industry events. In addition to Chemours, he’s worked for the National Institute of Standards and Technology. Dr. Allgood has held a variety of research, development, business, technical service, training, and applications development positions with Chemours. Most recently, he has focused on the development of low-GWP refrigerants—including Chemours Opteon™ brand refrigerants—and educating industry professionals about the changing regulatory landscape and A2L refrigerants on the market.
AAON Adopts A2L Refrigerant R-454B
TULSA, OK, May 14, 2024 — AAON, Inc. announced its transition to the low Global Warming Potential (GWP) refrigerant, R-454B, across its high-performance, energy-efficient commercial HVAC systems product line. Sources report the decision aligns with upcoming 2025 low GWP refrigerant regulations but also serves to demonstrate AAON's leadership in sustainable HVAC solutions.
AAON began accepting orders for R-454B units on Jan. 1, 2024 — a full year ahead of the EPA’s mandate to discontinue the use of refrigerants with GWPs above 700. As of this month, AAON is shipping equipment with R-454B to customers.
R-454B has a GWP of 466, an impressive 78% decrease from that of its predecessor, R-410A. This significantly minimizes the environmental impact of refrigerants used in commercial and industrial building systems.
"AAON consistently leads the implementation of technologies that surpass industry standards for sustainability," said Stephen Wakefield, AAON Executive Vice President, AAON Oklahoma. “By adopting R-454B early on, we're minimizing our environmental impact and paving the way for future innovations.”
Safety remains a top priority in the design and manufacturing of AAON units featuring R-454B. With its low burning velocity and stringent safety measures, the potential risks associated with its mild flammability as an A2L refrigerant are greatly mitigated. Components are meticulously selected and tested to meet industry standards, and the Company’s units are equipped with refrigerant leak detection sensors, enabling early leak detection and prompt intervention.
“AAON has and will always maintain a position of engineering and manufacturing leadership. Our aim is to remain years ahead of regulatory changes and competitor capabilities while delivering world-class performance and unmatched value,” said Gary Fields, AAON CEO.
As part of this transition, AAON will not increase prices for products utilizing R-454B, maintaining economic accessibility for its customers. AAON is currently delivering products with R-454B, and all AAON products will be available to configure with R-454B by June 1, 2024. The Company’s lead times for R-454B are normal, ensuring no disruption in service.
AAON was founded in 1988, and is a world leader in HVAC solutions for commercial and industrial indoor environments.
About the Author
Charles Allgood
Technical Fellow with Chemours
Charles “Dr. Chuck” Allgood holds a PhD in chemistry, has more than 30 years of experience in the HVACR industry, and is a respected speaker at many industry events. In addition to Chemours, he’s worked for the National Institute of Standards and Technology. Dr. Allgood has held a variety of research, development, business, technical service, training, and applications development positions with Chemours. Most recently, he has focused on the development of low-GWP refrigerants—including Chemours Opteon™ brand refrigerants—and educating industry professionals about the changing regulatory landscape and A2L refrigerants on the market.