I have a 6 year old Raypak (Rheem) m206a heater that will not light. It call for heat and then continues to spark, without lighting the pilot. I took the pilot out and cleaned everything including the orfice. I can visibly see the spark but smell no gas. (Valves are on, made that mistake before). I would like thoughts on where to go next. Can the pilot still be a concern even though I see the spark? Is there a concern with the regulator valve? I also see some people referencing board replacement. I'd hate to just start swapping expensive parts. Thanks