Retrofitting of R404a commercial refrigeration systems using R410a and R407f refrigerants

• European Union defines a phase-out program for high GWP HFC.
• Retrofitting of two R404a commercial refrigeration systems with lower GWP fluids.
• COP and cooling capacity assessment using R404a, R410a and R407f refrigerants.
• R410a and R407f outperform R404a at medium temperatures.
• R407f has comparable performances than R404a for low temperature systems.

This paper presents an experimental analysis about the retrofitting of two commercial stationary refrigeration systems marketed by an Italian leading company. Such systems operate both at medium temperature (MT), i.e. [−5; 10]°C, and low temperature (LT), i.e. [−25; −15]°C, and they are originally designed to work with hydrofluorocarbon (HFC) R404a, known as a high global warming potential (GWP) fluid (GWP = 3922). The goal is to investigate the performances of HFC R410a (GWP = 2088) and R407f (GWP = 1825), chosen as effective alternatives to HFC R404a. Such fluids are compatible with the refrigeration systems, non-flammable and easy-available. Furthermore, they meet the European Union (EU) restrictions in force in the next future, so that they are suitable to start the transition toward efficient and eco-friendly refrigeration systems. The experimental campaign shows the feasibility of adopting R407f and R410a for the MT refrigeration system and R407f fluid for the system operating at LT.