Jon, if you are referring to a TIFF 8800a, it does NOT sense carbon monoxide. I don't know where you are getting your information but it isn't from TIFF. FYI, Barcharach uses the same sensor tip on their Leakator 10. These sensors respond to hydrocarbons, moisture and heat. If your TIFF is speeding up and later confirm CO with an analyzer, the TIFF may have been sensing aldehyes, which are often present with CO.

You are using a very dangerous approach my friend. I suggest you rely on a calibrated CO analyzer for CO and leave the TIFF to sniffing combustible gases. Yes, it will give false positives such as soap bubble solution, pipe dope, silicone caulk and a number of other things. Do your homework and read the manual from TIFF. Also, it cannot quantify whatever it is sensing.

FYI, TIFF uses heptane for calibration so the meter will sense methane only down to 50 ppm. Many other brands can sense 10-20 ppm, which is about the level most noses can smell the gas odorant.

HTH,
Bob

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