1. The protection of thermocouple is burned by fire to the thermocouple. The thermocouple is heated to provide power to the solenoid valve. When the thermocouple is protected, you need to press the fire switch for a few seconds when igniting.

2. Sensing needle protection, (I don't know the specific name, just know the method of work), which is protected by the conductivity of the fire. When the fire is burned to the inductive needle, the fire -conducting inductance needle guidance (the two are equivalent to the switch in the circuit), and the solenoid valve is opened. The gas channel can be burned normally.