While I was up on the roof I also ran the brush down the oil flue, which had never been swept. House was built in '96. There was 1/4" of diesel soot in there. A lot of it fell into the Burnham so it got a very thorough cleaning too. NASTY mess to clean up. We went through 4 bags in the old garrage / car canister vac that we had outside with the hose & a few extension hoses running into the basement window. Time to junk that old vac now, LOL.