The results of tests using R449A (an HFO-based refrigerant blend initially developed as a replacement for high GWP HFCs R404A and R507) as a potential R22 alternative in refrigeration applications, were presented at last week’s International Compressor Engineering Conference at Purdue University.
R449A is marketed by Chemours as Opteon XP40. A blend of R32 (24.3%), R125 (24.7%), R1234yf (25.3%) and R134a (25.7%), it has a GWP of 1282.
The paper by Andrew Pansulla and Charles Allgood of Chemours looked at the results of an extensive study investigating the performance of R449A relative to R22 in both low temperature and medium temperature refrigeration applications.
Thermodynamic modelling, compressor calorimeter and controlled environment system testing is said to have shown that the capacity and COP of R449A are both expected to be near or exceed the capacity and COP of R22. While the mass flow of R449A will be 11-14% higher, the suction pressure delta between R22 and R449A is said to be a close enough match that changes to the thermal expansion valve will not be necessary.
Controlled environment system testing concluded that R449A uses slightly less energy compared to R22, a claim was verified in a real world system test by a supermarket that replaced its R22 with R449A in a medium temperature refrigeration rack.