- Nov 11, 2011
Just realized this ir is only rated to 716f possible false readings? @mdocod cod I try to get the ir gun as close to the surface as I can to make that measuring ratio small. Is this wrong? @3650 do you think I'd be better to leave the dampers open? I'm more concerned about stove top temps than the flue temps even though those are high to
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12:1 ratio.. at 1' away you're measuring about a 1" wide circle.
IR guns read most accurate when measuring a surface that is 90 degrees to the gun. A stove pipe is round so will always be imperfect in this regard. Expect slightly lower than actual readings from the IR gun, but to get the most accurate reading possible I would hold it about 6-8" away, directly at the middle of the pipe at a 90 degree angle to the pipe, around the side away from the face of the temp meter.
716F should be plenty of range for surface temps of the stove pipe, but might not be accurate for your stove top temps.
I think the "rule of thumb" is that single wall stove pipe will be about half the surface temp as the gases passing through it, but this varies depending on how much fluffy soot is deposited inside the pipe acting as insulation, and other factors, but if we're being honest, none of the other ways to measure a flue temp are much better.