Investigation of energy and exergy parameters using alternative fluids in hygienic air handling units instead of R22

In this study, energy according to the 1st law of thermodynamics and exergy analysis according to the 2nd law of R22 refrigerant used in direct expansion (DX) cooling units and chiller groups of Hygienic Air Handling Units, and zeotropic mixtures of HFC group 400, which is one of the alternative refrigerants that can be considered environmentally friendly theoretically carried out. In the study, the cooling load, which is the main purpose of the system, was taken as constant and the mass flow rate of the fluids was compared. In every fluid transfer to the cooling system, the drier filter will be renewed and the compressor oil will be changed in case of using R407C. According to the 1987 Montreal protocol, the sale of HCFC was prohibited as of 2010 and the use of HCFC for service purposes as of 2020. Hygienic air handling units are used in units such as operating rooms and intensive care units of university and state hospitals, and the cooling systems are cycled with 2nd generation R22 fluid. Air conditioning systems constitute a significant part of the cost in operating room and intensive care projects. For this reason, it will not be appropriate to renew air handling units before the operating rooms are brought to a certain standard. Determination of the most suitable fluid in terms of performance and disassembly in the cooling systems of the power plants will ensure the continuity of use of the system, as well as failure in the cooling system, gas leakage, etc. In such cases, it will be ensured that R22 is stored without dispersing into the atmosphere and necessary procedures are carried out in the disposal facilities. In the theoretical study, the data obtained using the Chemours Refrigeration Expert 1.0 program were compared. The evaporator temperature range of the cooling system is determined as -8°C, 0°C, +5°C while the condenser temperature is used at a constant 50°C temperature in the summer operation of hygienic air handling units. Alternative fluids are designated R407C (requires compressor oil change), R417A, R422A, R422D, R438A. Keywords: R22, Alternative Fluids, Exergy, COP, HCFC