In this master’s thesis, we investigated the potential for enhancing the energy efficiency of a household refrigerator-freezer by utilising phase change materials (PCMs). We developed a system for experimental analysis of the operation of a converted refrigerator-freezer under real conditions, with PCMs installed in several strategic locations: between the evaporator fins, between the evaporator and the rear wall of the freezer compartment, and in the cooling air guide channel. We analysed the impact of PCMs with phase transition temperatures of 2 $^°$C, 0 $^°$C, –21 $^°$C, and –24 $^°$Con the operation of the refrigerator. The installation of PCMs in the evaporator resulted in a 19.1 % reduction in the cooling capacity of the system and a 4.35 % increase in the ratio between the average compressor on-time and the full cycle (the so-called ON/OFF ratio). Using a combined approach, in which PCMs were installed in all three strategic locations, we achieved a 58.2 % reduction in the average cooling capacity and an 84.78 % increase in the ON/OFF ratio.
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