Since 1980s, under the stringent focus on the environmental issues, several new concepts are being introduced in the HVAC&R field. The first regulation under the American Innovation & Manufacturing (AIM) Act of 2020, appeared as a rule introduced by the US Environmental Protection Agency (EPA) in late 2021 that mandated an 85% nationwide phasedown in HFC refrigerants over the next 15 years.
Although HFC refrigerants had been a good substitute for ozone depleting CFC and HCFC refrigerants that were phased out since the late 1980s, the HFCs were found to be potent greenhouse gases with a medium to high global warming potential.
Thus in 2021, the EPA adopted a final rule accepting six refrigerant alternatives to HFCs for use in new residential and light commercial air conditioners and heat pumps. Later in October 2023, it was decided that beginning on January 1, 2025, certain technologies would need to restrict use of higher-GWP HFCs or HFC blends. Prohibitions will apply to the manufacture, distribution, sale, installation, import, and export of products containing restricted HFCs. Compliance deadlines and GWP limits varied based on sector
and subsector.
However, considering the concern raised by stakeholders that the January 1, 2025, compliance date for installing lower-GWP HFC residential air conditioning and heat pump systems may strand inventory of equipment, particularly equipment that was intended for new residential construction, an amendment was done on AIM Act in December 2023, this rule allowed for inventory of higher-GWP HFC equipment manufactured or imported before January 1, 2025, to be installed until January 1, 2026.
With this background, today, let us see how the global manufacturers and suppliers of the HVAC&R field are gearing up to tackle the upcoming situation – and which new refrigerant is gaining significant preference.
Lennox rolls out low GWP HVAC products
Recently, Lennox has introduced a few low Global Warming Potential (GWP) light commercial and ducted residential HVAC products to meet the 2025 low GWP Refrigerant regulations.
According to the company, the HVAC products released will be a comprehensive portfolio for the markets and will use the environmentally responsible refrigerant, R-454B, which reduces GWP by as much as 78%. With this move, Lennox continues to focus on high-quality, sustainable solutions while reducing energy consumption.
Asserting on their commitment, Prakash Bedapudi, Chief Technology Officer at Lennox, said, “Lennox is proud to support the adoption of low GWP refrigerants. By harnessing the power of advanced technologies, we will continue to not only meet industry standards, but also set new benchmarks for sustainability and performance.”
As announced in March at Lennox LIVE to the company’s dealer base, the residential line will include the more sustainable R-454B refrigerant in Lennox heat pumps and air conditioning units. For commercial equipment, the full line of commercial rooftop units and ducted split systems will feature R-454B refrigerant, including the award-winning Model L and Enlight families. Refrigerant detection systems engineered to detect and mitigate leaks will be available with Lennox products providing the added flexibility for customers of being indoor or outdoor compliant.
As products transition to meet the regulatory requirement, the need for forward and backwards compatibility increases. Earlier this year, Advanced Distributor Products (ADP) became the first manufacturer to launch a multi-refrigerant coil designed to help HVAC contractors and distributors transition from R-410A to any low GWP refrigerant. In addition to the coil, ADP also is transitioning air handlers to meet the new refrigerant requirement.
Daikin wins the 2024 SEAL Sustainable Product Award
SEAL (Sustainability, Environmental Achievement & Leadership) Awards is an environmental advocacy organization that honours leadership through its business sustainability awards. The SEAL Sustainable Product Awards honours innovative and impactful products that are literally ‘purpose-built’ for a sustainable future.
This year Daikin Comfort Technologies North America, Inc. (Daikin) has received a 2024 Seal Sustainable Product Award for the Daikin ATMOSPHERA, the first single-zone ductless heat pump system in North America with R-32, a low GWP refrigerant.
The Daikin ATMOSPHERA single-zone ductless inverter heat pump system is ideal for spot cooling and heating needs in residential and commercial spaces. In addition, it is an effective source of heat to offset old, inefficient furnaces or boiler heating systems. The Daikin ATMOSPHERA ductless system is easily applicable to both renovations, for areas that may not have had prior heating or cooling, and new construction, for areas where it is desirable to have comfort control of a single area such as an office, bedroom, or living area.
Focusing on their achievement, Marc Bellanger, Marketing and Communication Vice President, Daikin, said, “Daikin is committed to decarbonization and electrification efforts, and with the launch of Daikin ATMOSPHERA in 2021, Daikin led the industry in North America with the switch to the next generation of refrigerants that have a lower GWP compared to conventional refrigerants like R-410A.”
Johnson Controls choose to use Opteon XL41
According to the information from Johnson Controls, they have selected Opteon XL41 (generically known as R-454B) as the refrigerant replacement for R-410A in all their residential, light commercial and commercial ducted HVAC applications.
There are a few strong reasons behind their decision:
- R-454B has the lowest GWP with the best outlook for long-term viability. This reduces the likelihood that another refrigerant transition will be necessary with a future regulatory change.
- R-454B temperatures and pressures are much like R-410A, resulting in similar system designs and a reduced learning curve for equipment service technicians.
- R-454B provides up to a 78% reduction in GWP while still enabling the opportunity for optimized unit efficiency and decreased energy use.
Epilogue
As far as the latest refrigerant is concerned, the zeotropic blend of 68.9% difluoromethane (R-32), a hydrofluorocarbon; and 31.1% 2,3,3,3-tetrafluoropropene (R-1234yf), a hydrofluoroolefin, known as R-454B is the most recent choice of the industry globally. R-454B is also known in different trademarked names like Opteon XL41, Solstice 454B and Puron Advance.
Many manufacturers including Lennox, Mitsubishi Electric, Carrier, Johnson Controls are already using R-454B (a blend of R-32 with an olefin). Others too are following the course. But, some are still favouring R-32.
However, according to a blog from Trane, “Trane engineers tested all the possible low-GWP alternatives to transition away from the higher GWP refrigerant R410A and concluded that the most sustainable and future-proof refrigerant is R454B, excluding R32.”
To explain why R454B is a better choice, the blog states, “When comparing R454B and R32, most criteria are equal or nearly equal, such as: Performance, Toxicity, Flammability and Servicing. Studies prove that the glide of R454B is insignificant, and that no mechanical compensation is required to ensure that the unit runs with the performance it was originally designed for.
Therefore, the real basis of comparison resides in 3 facts: direct GWP, operating maps and long-term compressor reliability.
- Direct GWP: Right now, the globally accepted direct GWP threshold by HVAC system designers and building consultants is 750. R32’s direct GWP exceeds this threshold, and is 45% higher than R454B’s, making R454B the more sustainable choice. The lower the GWP, the better.
- Operating maps: The refrigerant in your system affects the limits within which it will optimally perform, also known as the unit’s operating maps. The larger the operating map, the better, because it allows a lot more flexibility.
Because R32 generates a compressor discharge temperature that is higher than R454B, the R32 operating map is, in turn, limited and this reduces application flexibility.
A unit with R454B outperforms a unit with R32, with its extended cooling and heating capabilities particularly when the need is to deliver higher leaving hot water temperatures at lower ambient air temperatures. We also see improved seasonal efficiency for units running with R454B. Another benefit of wider operating maps is that it is easier to replace a gas boiler, eliminating the problematic dependency on fossil fuels.
- Compressor reliability: Because higher compressor discharge temperature means higher refrigerant pressure inside the compressors, this all translates into unnecessary stress and accelerated wear on the compressor, shorter compressor lifetime and ultimately less reliability. This can be greatly lessened or avoided altogether with the use of a compressor operating with R454B.”
Thus, they conclude R454B is the best-balanced choice to replace R410A for all your building projects where a scroll chiller, heat pump or rooftop unit is needed.
By P. K. Chatterjee (PK)
