The aim of this study is to investigate the effects of superheating and subcooling values on the cooling
performance of a vapor compression refrigeration cycle. For this purpose, a refrigeration cycle with cooling
capacity of 8 kW using R404A was examined by changing superheating and subcooling values. Energy, exergy
and entropy balances were applied for evaporation and condensation temperatures of 0℃ and 45℃, respectively.
The coefficient of cooling performance (COP), the amount of energy transfer, rate of exergy destruction and
rational exergy efficiency of each components (evaporator, compressor, condenser and expansion valve) and
the whole system were determined. The compressor work, coefficient of performance and second law efficiency
increased by 0.7%, 1.61% and 1.56%, respectively, per one-degree increment of superheating in the evaporator.