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Tankless Combustion testing

Bart Vaio
Bart Vaio Member Posts: 56
My customer was complaining of a bad smell out near the flue so I set up the analyzer. It all seems ok but the O2 seems a little lean on low fire at 12% This is the first tankless I have ever tested (always boilers and forced air) does this look normal to you guys? Eff seems about right, nox seems nice and low as with CO. Any Ideas? results and unit spec attached


  • Bart Vaio
    Bart Vaio Member Posts: 56

    Jpeg of the scans seems blurry here is the word file..
  • Mitch_4
    Mitch_4 Member Posts: 955

    you check withTagaki tech? they should be able to tell you the ranges you should be seeing.
  • Jim Davis_3
    Jim Davis_3 Member Posts: 578
    Firing lean

    The heater looks extremely underfired in low-fire, and high-fire slightly. Any time O2 is above 9% efficiency is not what the analyzer calculates. Closer to 45%-50% in low fire and 65%-68% in high-fire. Most the ones I sold in the past ran close to 6%-7% in high-fire.

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