| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To prevent a freezing accident of a heat source apparatus and perform stable control even in an abnormal state where a flow rate on the heat source apparatus and external load apparatus side is rapidly changed. <P>SOLUTION: In the abnormal state where a pressure difference measurement value Pm between both headers by a differential pressure gauge 16 is excessively larger than a pressure difference set value Ps and/or where a flow rate measurement value Qm by pump flowmeters 20A-20C is excessively smaller than a flow rate set value Qs, a control device 8 determines the pressure difference set value Ps between both the headers and controls an opening of a bypass valve 12. In conditions in which maximum and minimum values of an operable flow rate of each heat source apparatus 2A-2C are set to be upper and lower limit values, respectively and a heating medium circulating flow rate circulated on the external load apparatus 9 side is distributed to each heat source apparatus 2A-2C, the flow rate set value Qs of each heating medium pump 3A-3C is determined. By substituting the pressure difference measurement value Pm between both the headers and the flow rate set value Qs of each heating medium pump 3A-3C to a calculation formula of pump operation frequency f, operation frequency fs of the heating medium pumps 3A-3C is determined, so as to control the operation frequency fs of the heating medium pumps 3A-3C. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
