I meant to sweep the flue awhile ago but finally got around to it. Also broke open the SootEater box and gave her a "spun". Worked good. Problem is, you have to add sections (3 ft. of them) as you go or you'd have a 16' ft U in the air trying to be spun by a drill. I tried it, and boy was it silly. Anyhow, great results. Another clean sweep. Less than a cup of brown coffee grounds.