Experimental Studies of a Domestic Refrigerator Using R290/R600a Zeotropic Blends

System performance of an existed 134a domestic refrigerator with propane/isobutane (50/50%) zeotropic blend is measured as a drop-in substitute. An in-house experimentations test facility was developed. The experiments are conducted under various charge condition to find optimum charge. Experiments were conducted at constant load condition. The optimum charge is measured as 60 g with R290/R600a (50/50%) zeotropic blend and the lowest temperature is recorded as -3.5°C.