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Lower-GWP Non-Flammable Refrigerant Blends to Replace HFC-134a



Harrison M. Skye, Piotr A. Domanski, Mark O. McLinden, Valeri I. Babushok, Ian Bell, Tara Fortin, Michael Hegetschweiler, Marcia L. Huber, Mark A. Kedzierski, Dennis Kim, Lingnan Lin, Gregory T. Linteris, Stephanie L. Outcalt, Vance (Wm.) Payne, Richard A. Perkins, Aaron Rowane


Non-flammable, lower global-warming-potential (GWP) refrigerants are needed to replace HFC-134a (GWP=1300) in military equipment. We previously used thermodynamic cycle simulations to screen 100 000+ refrigerant blends and identified 23 candidate replacements. In the present study we narrowed the candidates to three "best" blends and measured their "drop-in" performance in a military environmental control unit (ECU) tested in environmental chambers. Through simulations, the laboratory-measured performance was extrapolated to that of ECUs equipped with a compressor modified for each blend to provide the same system capacity while maintaining the isentropic efficiency of the original HFC-134a compressor. R-513A (GWP=573) and Tern-1 [R-134a/1234yf/1234ze(E) (49.2/33.9/16.9 %mass), GWP=640] are good replacement blends for HFC-134a, offering a similar capacity and COP at GWP reductions of 66 % and 51 %, respectively. These fluids do not present significant application difficulties. For a greater reduction of GWP, R-515B (GWP=344) can be considered but it requires further development.
Proceedings Title
Proceedings of the 26th IIR International Congress of Refrigeration: Paris, France, August 21-25, 2023
Conference Dates
August 21-25, 2023
Conference Location
Paris, FR
Conference Title
26th IIR International Congress of Refrigeration


Air conditioning, Coefficient of performance, Cycle simulation, Flammability, Low GWP, HFC-134a replacement


Skye, H. , Domanski, P. , McLinden, M. , Babushok, V. , Bell, I. , Fortin, T. , Hegetschweiler, M. , Huber, M. , Kedzierski, M. , Kim, D. , Lin, L. , Linteris, G. , Outcalt, S. , Payne, V. , Perkins, R. and Rowane, A. (2023), Lower-GWP Non-Flammable Refrigerant Blends to Replace HFC-134a, Proceedings of the 26th IIR International Congress of Refrigeration: Paris, France, August 21-25, 2023, Paris, FR, [online],, (Accessed May 21, 2024)


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Created August 21, 2023, Updated September 26, 2023