From the viewpoints of energy saving and environmental impacts, we have been studying Chemical heat pumps (CHP) especially focusing on using calcium systems. The CaSO₄/ CaSO₄·1/2H₂O gas-solid reversible reaction is used to store around 393K and release hot/cold heat. In this paper, we studied the energy efficiencies of CaSO₄ CHP in heat enhancement mode for commercial use with various cases. As a result, it is found that the stored heat is converted/released at 353K /278K level hot/cold heat. The CaSO₄ CHPs could be commercially used for wider operating temperature ranges in appropriate heat source conditions. Furthermore, the thermal efficiency was obtained to be more than 1.3, and the coefficient of performance (COP) was obtained to be about 18. It means the CaSO₄ CHPs could be more efficiently than other types of heat pumps