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yellow flame results are in...

Timco Member Posts: 3,040
I found the flames only turned yellow when the crawl hatch door was left open and fresh, cool air rolled in on the burners directly. When I closed the hatch door behind me to take a proper reading of the running conditions, it went blue and the readings changed. Unit was set to 3.4"WC when tested, and shot up to 200ppm CO when adjusted to 3.5 as sticker showed. I left it at 3.4 where I found it as the #'s were better.

Access door open= 64.7% ex air, 359* stack, O2 8.8%, CO2 6.8%, CO 73ppm, COAF 126ppm.

Access door closed= 50.9% ex air, 362*stack, O2 7.6%, CO2 7.5%, CO 78ppm, COAF 123ppm.

It doesn't take a genius to figure out that when cool fresh air flows across running burners that the flames will turn yellow...

Just a guy running some pipes.
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