Fig. 10 shows the COP improvement comparison for R32 and R410A. In the heating mode as shown in Fig. 10a, the COP improvement increases as the injection ratio. The maximum COP improvement for R410A and R32 was observed to be 18% and 11%, respectively at the ambient temperature of "18 #C. Fig. 10b shows the cooling COP variations. As the injection ratio increases, the COP even decreases rapidly, and this is quite obvious for R32. Therefore, vapor injection is more beneficial for the heating application compared to the cooling application. 
Fig. 11 shows the total system power consumption variation comparison. Typically the injection ratio increases the power consumption, because the increasing injection ratios mean that the compressor needs to compress more refrigerant. For R32 at the cooling mode, the power consumption increase is quite remarkable. This explains the reason of the quick COP degradation in Fig. 10b as the injection ratio increases.