HEAT SOURCE SYSTEM

Upon newly installing a system or installing an additional heat source apparatuses, manual adjustment of a number-of-units control device should be eliminated. Provided is a heat source system including a plurality of heat source apparatuses connected in parallel; and a number-of-units control device 100 that controls on and off of the plurality of the heat source apparatuses and allocates a load to an active heat source apparatus according to a load demand, wherein the heat source apparatuses each possess COP map unique to the respective heat source apparatuses that indicates a relationship among operating status, coefficient of performance, and load factor, each of the heat source apparatuses sets the appropriate operating region in correspondence to the operating status from the COP map and reports it to the number-of-units control device 100, and the number-of-units control device 100 performs number-of-units control of the heat source apparatus and load allocation on the basis of the appropriate operating region that is reported from each of the heat source apparatuses.