Flue sarfing, tester

[NW Mailing List]

Ok, if this has been discussed before...I saw a picture in the front page scrolling and couldn't grab it.  It said flue tester...it was a drawing actually.Searched, didn't find what I thought it said.
Ran across something called flue sarfing.  Any discussion on that would be appreciated.
Mike Shockley
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