The study investigates the effectiveness of substituting R404A refrigerant with the more environmentally friendly hydrocarbon refrigerants R290 and Minus50 (R290/R170) in a commercial dual-temperature refrigerating and freezing storage unit.A series of discussions and analyses were performed using varying quantities of refrigerant fillings and with various system loads.Temperature expansive valves and a concentric tube-based supercooling heat exchanger were used in the dual-temperature refrigeration system to compare performance when the system had no load, a 150 W fixed load, and a dynamic load of 18 kg of water.The discrepancies between the results for cooling efficiency, consumption power, system work input, and coefficients of performance (COP) and actual measurement data were examined.The results indicated that the cooling rate of the hydrocarbon refrigerants R290 and Minus50 were superior to R404A, regardless of whether the system was operating with or without a load, and that the power consumptions were approximately 11% and 28% lower, respectively, than that of the R404A;the specific volume of the R404A was approximately 33% that of the hydrocarbon refrigerants R290 and Minus50.Consequently, the R404A had the least compressor work input among the three refrigerants.This study calculated that the energy factor (EF;i.e., the refrigerator performance benchmark) of the unit was 3.52 when using the R404A, 4.04 using R290, and 4.76 using Minus50.