What about the wool material that looks like ambers. Can that material cause sooting? I had one of the tech supports one time tell me to spread it on the flame trail to light a bottom flame. I came across a log set last week that was sooting the hearth and it had some of this wool material on it. I did not like that log set, don't remember the company but their burner system was basically a metal box with holes in it. Furtherest side from the inlet wasn't burning consistent as the gas was going to the larger cutouts instead of the small holes.