jmmazzy wrote: I'm not a fan guy but I would say it was creating some kind of a turbulence.
Don't think turbulence was your problem Mazzy. You weren't drawing all the draft you were supposed to (or could have been) when the fan was in operation. Everywhere you weren't close to the tube with your fan was lost airflow that was desperately needed.
I think it also hurt you on your idle fire. Picture this if you will. You have 1/4" times what....10" or so around the fan and tube which draft can flow. Now open half of that up to 1/2". I would think air velocity would suffer. I'm not an engineer nor did I stay at a Holiday Inn last night so maybe this is all BS. Just a theory.
Glad you've got it on the run now though, happy heating!