Hot water supply system

A hot water supply system, comprising:

• a plurality of hot water suppliers connected in parallel to a common hot water outlet route,
• wherein each of the plurality of hot water suppliers comprises:
• a first communication unit and a second communication unit connectable to different communication lines;
• and
• a controller that controls an operation of the hot water supplier,
• wherein the controller of each of the hot water suppliers is configured in advance to have a supervisory control function for cooperatively operating a group of hot water suppliers communicatively connected in series via the communication lines, and
• between adjacent hot water suppliers in a series connection constituting the communication connection, the first communication unit of a hot water supplier on an upstream side, which is one predetermined end side of the series connection, and the second communication unit of a hot water supplier on a downstream side, which is the other end side of the series connection, in the group of hot water suppliers are communicatively connected sequentially,
• wherein each of the controllers is configured to execute:
• a first control processing that recognizes, based on presence or absence of communication by the first communication unit and the second communication unit, whether the controller is a leader controller installed on a leader hot water supplier positioned at a most upstream of the series connection in the group of hot water suppliers and operating to execute the supervisory control;
• an end follower controller installed on an end follower hot water supplier positioned at a most downstream of the series connection in the group of hot water suppliers;
• or a middle follower controller installed on a hot water supplier communicatively connected between the leader hot water supplier and the end follower hot water supplier, and
• a second control processing that transmits data initialized by the leader controller to the end follower controller while changing it according to a predetermined rule by each of the middle follower controllers, and transfers the data further changed by the end follower controller according to the rule, with content unchanged, to the leader controller by each of the middle follower controllers, wherein
• the data is a counter value that, after being initialized by the leader controller, is changed each time by a specified value by the middle follower controllers and transmitted to the end follower controller, and after being further changed by the specified value by the end follower controller, is transferred, with the value unchanged, to the leader controller by each of the middle follower controllers, and the leader controller recognizes, based on an initial value of the counter value, an address of the hot water supplier on which the controller is installed,
• the end follower controller and each of the middle follower controllers recognize, based on the counter value after being changed each time by the specified value, an address of the hot water supplier on which the controller is installed, and
• each of the hot water suppliers further comprises a display part for displaying the address recognized by each of the controllers.