Patent ID: 7902959

Claim:
A radio communication system of a water heater comprising a slave set which remotely operates a water heater main body by radio communication, and a master set which continuously communicates with the water heater main body by wired communication and which intermittently communicates with the slave set by radio communication to relay communication between the water heater main body and the slave set, wherein the slave set includes a switch section for remotely operating the water heater main body, a display section for displaying operation information at the switch section and monitor information of the water heater main body, a slave set radio communication circuit which intermittently communicates with the master set by radio communication, and a slave set communication control section for controlling in synchronization with communication timing of the master set; the master set includes a wire communication circuit which continuously communicates with the water heater main body by wired communication, a master set radio communication circuit which intermittently communicates with the slave set by radio communication, and a master set communication control section which continuously receives monitor information of the water heater main body from the water heater main body and which controls such that the received monitor information is intermittently transmitted to the slave set together with transmission-start time point information indicative of next data transmission time point; the master set communication control section of the master set controls such that when the master set receives an instruction from the slave set to change a hot water supply temperature of the water heater main body to a requested temperature by the slave set, an operation instruction to change the hot water supply temperature of the water heater main body little by little is transmitted to the water heater main body until the hot water supply temperature reaches the temperature requested by the slave set, and the temperature requested by the slave set is transmitted to the slave set instead of the hot water supply temperature of the water heater main body including the monitor information until a particular time during which the hot water supply temperature of the water heater main body reaches the temperature requested by the slave set elapses.