PERFORMANCE ANALYSIS OF R22 an‎d ITS SUBSTITUTES IN AIR CONDITIONERS

The aim of this paper is to evaluate the performance of refrigerants R22, R407C, R432A, R438A and NM1 (R32/R125/R600a) in order to find a suitable alternative refrigerant for HCFC 22. For this purpose energy as well as exergy analysis has been performed using NIST Cycle-D program for vapour compression refrigeration cycle design and TEWI (total equivalent warming impact) has also been computed for these refrigerants. From the analysis it is found that the values of COP were nearer to those of R-22, e.g. at 25, 45 and 55 °C condensing temperature, COP of R432a is lower than that of R22 by about 5.5%, 4% and 4.38% respectively. The results show that by considering the energetic efficiency, exergetic efficiency, TEWI and flammability simultaneously, R438A proves to be a better option to replace R22.