To provide a technique capable of combining energy conservation and stable cold water supply, in a heat source integration control system including unused hot water input type absorption cold and hot water machine.

A heat source machine operation control method uses energy in order from a small driving source of an energy source unit such as, preferentially solar heat and cogeneration waste heat, electricity, and fuel (city gas and the like). Since an unused hot water input type absorption cold and hot water machine operated by simultaneously inputting hot water and fuel forcibly blocks input of fuel until the input turn of fuel comes, the unused hot water input type absorption cold and hot water machine performs operation as if discriminated as two heat sources. Consequently, a hot water input type refrigeration machine is not needed to be installed alone, and reduction in initial cost and space-saving can be enabled.