That homeowner in Nashville who told me my brush was scratching her flue liner

I was sweeping a 20 year old clay liner outside Nashville last month and the homeowner came out and said she could hear scraping sounds that were different from other sweeps she'd hired. She asked if I had checked the brush size against the liner diameter first. I shrugged it off until I measured and realized I was using a 10 inch brush on a 8 inch flue. Changed to a 7 inch wire brush and the difference was night and day. No more scraping sounds and I got way more soot out in one pass. Has anyone else had a customer call them out like that on a basic thing?

2 comments

2 Comments

spencer_thomas47d ago

Man, that's actually super common and honestly I gotta say your brush sizing might not be the only thing off here. You mentioned going from a 10 inch to a 7 inch on an 8 inch flue and that's still too big. For an 8 inch clay liner you really want a brush that's about 1/4 to 1/2 inch smaller than the flue diameter, so that 7 inch is fine for the sides but if the liner has any buildup or slight narrowing it'll still scrape. Also, those wire brushes can gouge clay liners over time even if they fit right. I've seen guys use poly brushes or just stiff nylon ones for clay liners and they don't make that scraping noise at all. The homeowner was probably just trying to help you out and she was right to question it.

smith.blair6d ago

And yeah @spencer_thomas4, that poly brush tip is something I've been wondering about too. I've always used wire brushes on clay liners and never thought twice about it, but now I'm paranoid I've been damaging them. Do you think switching to poly makes enough of a difference to justify buying a whole new set, or is it more of a long-term wear thing that only matters if you're doing this every day? I've heard mixed things about whether nylon bristles actually clean as well as wire on heavy creosote.