The basic working principle of gas water heaters is that cold water enters the water heater and flows through the water-air linkage valve body under the action of a certain pressure difference of the flowing water, pushing the water-air linkage valve, and at the same time pushing the DC power micro switch to turn on the power and start the pulse The igniter, at the same time, open the gas solenoid valve, and continue to automatically re-ignite through the pulse igniter until the ignition is successfully entered into the normal working state. This process will continue for about 5-10 seconds. When the gas water heater is in operation or ignited When there is a lack of water or water pressure, lack of electricity, lack of gas, excessive hot water temperature, accidental blowing out and other faults in the process, the pulse igniter will automatically cut off the power supply by detecting the signal feedback from the induction needle, and the gas transmission electromagnetic valve In the case of power shortage, it will immediately return to the original normally closed valve state, that is to say, the gas has been cut off at this time, and the gas water heater will be turned off for safety protection.