The gas control valve on my old A.O. Smith boiler needs replaced. It is an Essex CC-251, that is no longer made and no one can find a direct replacement for. It is a standing pilot for a 100k BTU boiler. The weird thing is it has 3 connections for the pilot instead of just the normal gas line and thermocouple. I can't figure out what the third does. I have disconnected it and both the pilot and main burner still operate normally. Can anyone tell me what it does? I have attached pics and have more if they would help.
![IMG_0410.JPG IMG_0410.JPG](https://www.snowest.com/forum/data/attachments/324/324686-2f487705aba6fffc83b767d408612f8b.jpg)
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![IMG_0397.JPG IMG_0397.JPG](https://www.snowest.com/forum/data/attachments/324/324685-3a0784204ae3155688322829ecd9377b.jpg)
![IMG_0410.JPG IMG_0410.JPG](https://www.snowest.com/forum/data/attachments/324/324686-2f487705aba6fffc83b767d408612f8b.jpg)