New refrigerant options await ASHRAE approval
20th June 2021
USA: With seemingly no let up in refrigerant developments, eight new gases have been submitted for ASHRAE 34 classification, in addition to two refrigerants from Honeywell and Chemours receiving R-numbers.
ASHRAE Standard 34 assigns reference numbers, safety classifications and refrigerant concentration limits on all new refrigerants. The Honeywell and Chemours refrigerants have already received designations, and now await public review and final action.
The list includes Daikin’s new development gas, D1V140, and its blend component HFO1132(E), (revealed by the Cooling Post last week (Daikin develops more efficient refrigerant for electric vehicles)), three new hydrocarbon blends, what appears to be a further ultra low GWP refrigerant, and two new Koura gases based on R1132a.
Possible R1234yf alternative
Koura has revealed that one of its new refrigerants is, like the Daikin gas, targeted for use in electric vehicle HVAC systems.
While R1234yf has become the global industry standard low GWP refrigerant for vehicle air conditioning systems, its efficiency is of concern in new and future electric vehicles. Unlike conventional internal combustion engined vehicles, electric vehicles cannot use the engine waste heat for interior heating. Instead a heat pump system is used, increasing the load on the battery and severely reducing an electric vehicle’s range in cold climates.
The new Koura refrigerant blends 6% R1132a and 13% R32 with R1234yf to produce a refrigerant with a GWP of around 91. While this is higher than Daikin’s proposed new gas, it is still well within the 150 GWP maximum under the European MAC directive.
R1132a is an A2 gas commercially produced at kilotonne scale as the starting material for fluoropolymers. It has also been incorporated in R473A, Koura’s recently announced low GWP alternative to R23 in ultra low temperature applications (Koura’s R473A brings lower GWP for ultra-low temps).
The R1132a molecule also features in another new Koura refrigerant submitted for ASHRAE 34 classification. Thought to be designed for HVAC applications, this refrigerant blends 6% R1132a with 42% 32 and 52% 1234yf. This would give it a GWP of around 286.
Low temperature
Italian company Angelantoni Test Technologies has also submitted a new refrigerant, which tweaks the blend proportions of its recently announced ultra low temperature gas, R472A. The new refrigerant, R472B, decreases the proportion of CO2 and R32, increasing the amount of R134a (58% CO2, 10% R32, 32% R134a). It creates a refrigerant with a GWP of 526.
Honeywell R448 blend
Recently receiving an ASHRAE designation is Honeywell’s R448B, a tweak on the blend proportions of its now well established R404A refrigeration retrofit, R448A. The new gas is still going through public review and awaits final ASHRAE approval.
The existing gas, R448A, which is said to have been used in over 30,000 installations since its release in 2015, is a complex blend of R32, R125, R1234yf, R134a and R1234ze(E) (26%/26%/20%/21%/7%). The proposed R448B blend reduces the proportions of both R32 and R125 to 21%, while increasing R134a to 31%. The GWP is slightly less – 1321, compared to R448A’s 1387.
Not to be left out, Chemours has received a designation of R427C and an A1 classification for its blend of R32, R125, R143a, R134a. It’s intended application is unclear, but it is a variation on Arkema’s R427A, an R22 retrofit gas for air conditioning, heat pumps, and refrigeration.
New participants
The three new hydrocarbon blends have all been submitted by new entrants to the ASHRAE approval process. The Huazhong University of Science and Technology, a public research university based in Wuhan, has submitted two blends comprising R1270 (propylene) and R600a (isobutane) in vastly different proportions.
The other, a blend of propane, butane and isobutane comes from Brazilian LPG gas distribution company, Cia Ultragaz S/A.
