When you are dealing with burners you are dealing with a fairly high pressure system the idea that the CO was forced back into the burner and into the lines somehow is pretty impossible. If there are flames coming out then there is no way for anything to go back into the lines
Thats really good to know. I have never experienced the solid orange flame any time before lighting the coals (3 months), and I haven't experienced it at all today. Seems really strange to me.
Also, a side note. I don't think its the gas line because my hot water heater and furnace are on the same line and do not have the problem.
I know its the coals because it can go from full blue to full orange the second I place the coal in the flame, and never go orange any other time.