Unpopular opinion: My uncle said to never use a wire brush on a clay flue liner

I argued with him for months, but after a job in Burlington where I saw a cracked liner from exactly that, I had to admit he was right. Anyone else have an old-school tip that actually held up?

3 comments

3 Comments

susan_wells15d ago

Huh, "wire bristles can get stuck in the clay and rust" - I mean, I get the logic, but is it really that common? I've been using wire brushes on old clay liners for years and never had an issue. Feels like one of those things that sounds scary but doesn't happen all that often.

jesse_barnes372mo ago

Those wire bristles can get stuck in the clay and rust, which makes the crack worse over time. My old boss used a stiff nylon brush instead, said it was just as good for cleaning out soot. He'd attach it to fiberglass rods, same as you would with a metal one. It always did the job without any risk of damage.

sethc122mo ago

Totally agree, I saw that exact rust problem on a job last year. The homeowner had used a wire brush on a hairline crack and it looked way worse a few months later. Switched to a heavy-duty nylon brush myself and it cleans the creosote out just fine. You don't get those little metal bits left behind to cause more trouble. It's one of those small changes that just makes sense.