b5a5d860_for_any_fuel_gas_fired__boiler__Item
[Safety] The small pilot burner turns off as soon as the main burner is lit. [Reason] A single flame detector is used in this system. It must be located to see both the small pilot flame and the large main flame. If the pilot operates all the time, and a problem with the main flame caused it to go out, the system would not detect the flame loss. At high burner firing rates, the pilot flame may be too small to reignite the main flame. Notes: With a separate flame detector for both the main flame and the pilot flame, the pilot can remain on all the time. Also, with a large pilot flame (usually at least 10% of the main flame) reignition of the main flame is very likely and the pilot can remain on even with a single flame detector in use. [Item] 
Interrupted Pilot Burner
Safety controls for any fuel gas fired  boiler
Item