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.

The gas water heater is mainly composed of a valve body assembly, a main burner, a small fire burner, a heat exchanger, a safety device, etc. It also includes the flue of a flue water heater and the forced exhaust device of a forced exhaust water heater. The valve body assembly controls the entire working program of the water heater, including water valves, gas valves, microswitches, and igniters. When installing a water heater, valves should be installed on the inlet, outlet, and gas pipes.