Performance Study of Zeotropic Refrigerant Mixtures in an Air Source Heat Pump Water Heater

Experimental comparison of three kinds of zeotropic refrigerant mixtures including of R417a, 80%R22 and 20%R142b, 70%R22 and 30%R142b in a air source heat pump water heater was studied, and the heating capacity, input power, COP, exhaust pressure and temperature of the compress at ambient temperature 35 degrees C and 15 degrees C were tested. The results show that the heating capacity of R417a is about 3.7% less than that of 80%R22 and 20%R142b, and 5.8% more than that of 70%R22 and 30%R142b; the input power of R417a is about 6.2% more than that of 80%R22 and 20%R142b, and 12.6% more than that of 70%R22 and 30%R142b; COP of R417a is the lowest of the three, and it can obtain the hot water more than 60 degrees C, but is hard to keep good performance under low temperature condition.