Toshiba Carrier is said to have described R466A, Honeywell’s new non-flammable R410A replacement, as “promising” after initial performance testing in a VRF air conditioning system.
The findings were presented at a symposium on new refrigerants organised by the Japanese manufacturers’ association JRAIA in Kobe last month.
Honeywell announced the development of R466A in June last year to enormous global interest. To be marketed by Honeywell as Solstice N41, the new refrigerant appears to answer a demand for a non-flammable, low GWP alternative for R410A. Previous solutions R32 and R454B are “mildly flammable” A2L gases, suitable for residential split and smaller commercial units but not acceptable for larger-charge VRF systems. At 733, R466A has a similar GWP to the A2L alternatives.
While the Cooling Post has not seen the test results, according to Honeywell the efficiency, cooling and heating capacity of VRF systems using R466A is “very similar” to those using R410A. Design pressures of R466A were also slightly lower than R410A. Its life-cycle climate performance, when including direct and indirect emissions, shows emissions from the use of R466A to be 30% lower than R410A.
Excited
“To meet Japan’s HFC phase-down requirements in support of the Kigali Amendment, Toshiba Carrier is actively seeking a next-generation replacement for R410A that is energy efficient and safe for our customers and the environment,” said Toshiba Carrier in a statement.
“After the promising initial performance testing, we are excited to see if Solstice N41 can be a non-flammable, safe alternative to R410A that could contribute to the achievement of Japan’s HFC phase down goals. We have been engaging in reliability testing to handle the newly developed refrigerant in VRF systems.”
R466A mixes 49% R32 and 11.5% R125 with CF3I, a flammability suppressant.
Validation
Compressor manufacturer Bitzer, in its most recent Refrigerant Report, described the differences between R410A and R466A as “relatively small” in terms of thermodynamics. Volumetric refrigerating capacity, pressure levels and discharge temperature were reported to be slightly higher, and the refrigerant mass flow about 15-20% higher. The temperature glide is also very low.
“The Toshiba Carrier finding in the initial testing is a great validation that our nonflammable, reduced GWP Solstice N41 technology is poised to solve a key problem, becoming the next global standard for refrigerants,” said Sanjeev Rastogi, vice president and general manager of Honeywell Fluorine Products. “What we invented and achieved in Solstice N41 can be a true breakthrough as it provides the industry with a near drop-in solution that maintains safety levels across the value chain while offering significant environmental benefits.”
Honeywell expects full ASHRAE approval this month, with availability for OEMs as early as mid-2019.
