A thermodynamic comparison between heat pump and refrigeration device using several refrigerants

In the case of freezer mode, entropy reduction in compressor and COPL drop to very low values are other substantial issues discussed in this research. It was also revealed that, optimal charge amount of the freezer is 15-25% lower than that of the system when works in HP mode. Experiments showed that, in some cases COP of the heat pump was even more than 100 times greater than that of the freezer.