Heat source system

1. A heat source system comprising:

a plurality of heat source apparatuses connected in parallel; and

a number-of-units control device that controls on and off of the plurality of heat source apparatuses and allocates a load to an active heat source apparatus according to a load demand,

wherein each of the heat source apparatuses is configured to;

possess COP information, unique to the respective heat source apparatuses, that indicates a relationship among operating status, coefficient of performance, and load factor,

set, at a predetermined timing, an appropriate operating region that is a load region where the coefficient of performance is equal to or more than a predetermined value from the possessed COP information,

when an operable region has been set on the basis of devices provided in the heat source apparatus, set a first load region that satisfies both the appropriate operating region and the operable region, and determine whether or not the first load region is narrower than a predetermined region set in advance, and

send any of the appropriate operating region when the operable region has not been set, the operable region when the first region is narrower than the predetermined region, and the first load region when the first region is not narrower than the predetermined region to the number-of-units control device at a predetermined timing, and

wherein the number-of-units control device performs number-of-units control and load allocation such that each of the heat source apparatuses is operated within the appropriate operating region or the operable region or the first load region which is received from the each of the heat source apparatus.

2. A heat source system according to claim 1 , wherein the heat source apparatus possesses, in such a manner as to be associated with each other, a second load region for further increasing operating efficiency in the heat source apparatus and a condition for employing the second load region and sends the second load region to the number-of-units control device when the condition for employing the second load region is satisfied, and

the number-of-units control device performs number-of-units control and load allocation such that the heat source apparatus to which the second load region has been sent is operated within the second load region.

3. A heat source system according to claim 1 , wherein

the heat source apparatus is a centrifugal chiller comprising:

a turbo compressor of either an inverter-driven variable-rotation-speed type or a fixed-rotation-speed type;

a condenser that condenses the refrigerant compressed by the turbo compressor;

an expansion valve that expands the condensed refrigerant; and

an evaporator that evaporates the expanded refrigerant to cool chilled water.

4. A heat source system comprising:

a plurality of heat source apparatuses connected in parallel; and

a number-of-units control device that controls on and off of the plurality of heat source apparatuses and allocates a load to an active heat source apparatus according to a load demand,

wherein each of the heat source apparatuses is configured to;

possess COP information unique to the respective heat source apparatuses that indicates a relationship among operating status, coefficient of performance, and load factor, and

send the information related to the possessed COP information and an operable region when the operable region has been set on the basis of devices provided in the heat source apparatus to the number-of-units control device at a predetermined timing, and

wherein the number-of-units control device is configured to;

set, for each heat source apparatus, an appropriate operating region that is a load region where the coefficient of performance of each of the heat source apparatuses is equal to or more than a predetermined value on the basis of the information related to the COP information that is sent from the respective heat source apparatus,

with respect to the heat source apparatus from which the operable range is received, set a first load region that satisfies both the appropriate operating region and the operable region, and determine whether or not the first load region is narrower than a predetermined region set in advance, and

perform number-of-units control and load allocation such that the heat source apparatus in which the operable region has not been set is operated within the appropriate operating region thereof, the heat source apparatus whose first load region is not narrower than the predetermined region is operated within the first load region, and the heat source apparatus whose first load region is narrower than the predetermined region is operated within the operable region.

5. A heat source system according to claim 2 ,

wherein the condition for employing the second load region is such that the outside air temperature is equal to or lower than a predetermined temperature and the humidity is equal to or more than a predetermined humidity, and

wherein the second load region has been set to a range that the defrost operation is not needed.