Nouveau frigorigène à faible PRG pour remplacer le R404A dans les systèmes frigorifiques hermétiques (en anglais)

Un nouveau frigorigène à faible PRG visant à remplacer le R404A et qui allie un HFO, un HFC et un frigorigène naturel sera disponible dans le commerce l'année prochaine. (en anglais)
A new lower GWP replacement for R404A, which blends an HFO and an HFC with a “natural” refrigerant is to be made commercially available next year.

This refrigerant blend, R455A, developed by Honeywell, is being considered for ASHRAE classification as an A2L “mildly flammable” gas.

The refrigerant, marketing as Solstice L40X, consists of 75.5% R1234yf, 21.5% R32 and 3% CO2.

Honeywell has told the Cooling Post that R455A matches the capacity of R404A and has the same or better efficiency. Glide is thought to be around 6K. The addition of a small amount of CO2 is thought to boost system capacity.

Test results from its application in a single door reach-in freezer were the subject of a paper presented by Honeywell at the Purdue University compressor conference last year. The R404A freezer had an internal volume of about 700 litres and rated capacity of around 560W. The top-mount self-contained refrigeration unit had a nominal charge of 354g of R404A and comprised 373 kW hermetic compressor, air-to-refrigerant tube-in-fin condenser and evaporator, suction-line liquid-line heat exchanger and thermostatic expansion valve.

Initial drop-in tests showed that R455A had capacities below 90% of baseline tests with R404A and a slightly lower efficiency. However, when the original parallel-flow evaporator was altered to a counter-flow arrangement and the expansion valve adjusted to allow for R455A’s slightly lower pressure, the unit showed a 6% lower energy consumption and a near match in capacity.