Their first pulse is different. Flame-like ion pulse output is four lines, two ignition, two flame lines, thermocouple output pulse gas is a two-line, is for ignition.
Ion flame type solenoid valve common to the two switches, and each thermocouple is mounted on the respective body.
The same point is that, after switching on, when the plasma needle or thermocouple fire, their solenoid valves are kept open position.
When the fire goes out, their position solenoid valves are closed. Its role is to play a protective role breathe.