Retrofitting of R404a Commercial Refrigeration Systems with R410a and R407f HFCs Refrigerants

This chapter presents an experimental analysis about the retrofitting of two commercial stationary refrigeration systems marketed by an Italian leading company of the sector. Such systems operate both at medium temperature (MT) and low temperature (LT) and they are originally designed to work with the high global warming potential (GWP) hydrofluorocarbon (HFC) R404a fluid (GWP = 3922). The purpose is to investigate the performances of HFCs R410a (GWP = 2088) and R407f (GWP = 1825) chosen as effective alternatives to HFC R404a, due to their compatibility, non-flammability and market availability. Furthermore, such fluids meet the EU restrictions in force in the next future for high GWP HFCs. The experimental analysis compares the performances, in terms of COP and cooling capacity, of R404a and the two identified alternatives under different operating conditions, i.e. chamber and condenser inlet air temperatures. In case of comparable performances, significant environmental benefits are introduced by the adoption of R407f and R410a in the MT and LT refrigeration systems.