HOT WATER SUPPLY SYSTEM

In a hot water supplier system in which multiple hot water suppliers are communicatively connected in series via communication lines, cooperative control that automatically and promptly responds to removal of a communication line is realized. The hot water suppliers 100a to 100f 5 are configured to communicate with a hot water supplier on a downstream side via the communication line 9 connected to a first communication connector 121, and communicate with a hot water supplier on an upstream side via the communication line 9 connected to a second communication connector 122. In each of the first communication connector 121 and the second communication connector 122, a shorting pin 97 is connected together with the communication 10 line 9 by installation of a cable connector 95, thereby detecting connection of the communication line 9. When detecting that the communication line 9 is connected to the first communication connector 121 and the communication line 9 is not connected to the second communication connector 122, a controller 110 operates to perform a function of supervisory control for cooperative control of multiple hot water suppliers communicatively connected. Controller 112-- /111 42 44 3- -40 |Communicatiod Communication unit | unit 4 39 122 121 43 32 Hot water Hot water Amount of hot water supply supply start Increase standby supytr Water flow Water flow (combustion) Main 1 42 Open - detection - required +- Rotation Increase ove at a time Main 2 42 Open 42 Closed Start water supply (become sub) (combustion) sequentially as Sub 42 42 Closed required Closed