Experimental study of a novel double temperature chiller based on R32/R236fa

Highlights: • A novel double-temperature chiller with zeotropic mixture R32/R236fa is proposed. • The chiller is applicable for temperature and humidity independent control system. • Effects of mass fraction, fluid flow rate and temperature on chiller are studied. • The suggested mass fraction of R32 is around 60%. • The maximum COP and refrigerating capacity are 4.17 and 4.49 kW, respectively. - Abstract: A novel double-temperature chiller with zeotropic mixture R32/R236fa is proposed in this paper, and chilled water with two different temperatures is produced, such as low temperature water (T_L,out = 7 °C) and high temperature water (T_H,out = 16 °C). An experimental setup is established to test the performance of the chiller. Effects of mass fraction of R32 in mixture R32/R236fa (M (R32)), T_L,out, T_H,out and the heat transfer media flow rate on the performance of the chiller are studied. When T_H,out is 18 °C, T_L,out is 8 °C and M (R32) is 0.6, COP and refrigerating capacity are 4.11 and 4.42 kW, respectively. COP and refrigerating capacity increase as M (R32) increases. Exhausting pressure of the chiller increases with the increase of M (R32). As M (R32) is 0.6, exhausting pressure is about 1.95 MPa. Compression ratio decreases with the increase of M (R32). When M (R32) increases from 0.3 to 0.6, the compression ratio decreases from 3.0 to 2.9.