Burnt smell while running on the oil burner?

What diameter inlet do you recommend into the boiler room?

You can't use a power venter on the stoker. Somewhere in the threads is the inlet requirement. If I remember correctly, it's one square inch for every 4000 BTU, so around 55 sq. inches. Use a louvered shutter, similar to a dryer vent and it may only open a little bit.