The control system of a household gas water heater is an electronic control system, usually equipped with a flame detection device and a control device. The control system has electronic ignition, flameout protection, safety interruption, constant water temperature, overheat protection, incomplete combustion protection functions, as well as re ignition, human-machine telephone display, alarm function, and remote control function. There are three types of gas water heater time sequence controller, digital controller, and fuzzy controller.