What are typical flue gas results in a AFG

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Brock CCC forced air furnace with through the wall ventilator. Beckett AFG Burner, 100PSI Oil Pressure, 0.75 80' nozzle. Currently 02 = 8.9, CO2 = 8.9, CO = 0, Net Stack Temp = 677F, Eff = 71, and Ex Air = 70

I see where you are headed. Your best bet is to go to the Beckett web site and look up that burner. It should contain info you are looking for.

Thanks for the reply. The Beckett website says to back off the air until a trace of smoke is seen in the flame, then add air to drop CO2 reading by 2%. Does anybody who does flue gas analysis know what typical readings are?

The typical CO2 is between 11 and 12.5. Draft on negative draft appliances should be -0.02 over fire. The stack will vary greatly per unit.
Excess air is normally around 25%

Thank you for the info. As I suspected, my current readings show way too much air. I will try trimming down the air shutter to bring my CO2 up above 11.