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0-1 PPM CO?

Timco Member Posts: 3,040
Cleaned a TL Mighty Max, 199k, one zone. Lots of signs of condensing but cleaned up great.

My Fyrite 125 Pro (a few months past calibration missed calib day) was less than 20.9 O at startup so I knew a sensor was going but it did steady out on restarts. JUST put a new O sensor in last year. Measured 50-90ppm AF. Can't be right. Restart tester. Measures 10-12ppm. Better but now I don't trust it so yesterday I buy an Insight tester (Bacharach) and go back. 0ppm and probing around I find 1ppm, got 2ppm for a second before it went to 1ppm.

I don't think I've ever seen a cat 1 appliance that old be so low. Are the newer testers that much better and accurite? Has the older one always been reading higher? It's about 9-10 years older.

Just a guy running some pipes.


  • Tim McElwain
    Tim McElwain Member Posts: 4,628
    Does the new Insight have

    a NOX filter? If it does your CO Air Free will be very low say 0 to 5.
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