I have a flame out after 2 seecods ,

Sounds like you have a bad sensor.

Can you be more decriptive? Are you saying the main burner lights for a couple of seconds and then shuts down and repeats? If so, it may be as simple as cleaning the flame senser. However, this is just a guess with the info you have given.

The main burners light and then in 2 seconds the I have a flame out , I change the flame sensor anits the same problem.

Which sensor are you referring to.

Flame sensors hardly ever go bad. The rod or ceramic around the rod has to be broke for it to be bad. But they do get dirty and often. You can scrape it clean with a knife or with steel wool and give it a try. I would say in 26 years I may have replace 5 flame sensors but cleaned 1000s.

I agree completely T-Top.

Just curious now, maybe he is having a flame roll out problem? We may never know.