Glad I had Combustion Analizer...

[billygoat22]

have had three furnaces in last two weeks with odd readings and found issues with them, which would not have shown up otherwise.

Replaced a hx in an 80% Goodman. was third one going in, so checked it over pretty hard. The one I condemned looked like it had an obstruction it it that caused the sooting in hx.

put in new one and 7% O2 on it. took shutters off burners and a little better, but still not right. Called Goodman and found that there was a service up date on the propane conversion kit yrs ago (change in orifice size). Ordered the corrected kit to put in. (correct orifices by the nameplate BTW)

90% Rheem furnace w/ low O2, sooted in hx. hit 6000+ppm CO in flue gases.

90% Trane w/ hi O2. Had to take a number of parts off to find cracked parts leaking air into a transition fitting to inducer. New part ordered there as well.



w/o CA would have been back for sooted up hxs later, or worse.

[kdean1]

I hear you brother. I use mine on every gas furnace. I went to a no-heat call on Saturday which I repaired by cleaning the pilot orifice and replacing the thermocouple. Then I checked the furnace performance and found it to be within specs. However the house had 3 ppm CO! After some questioning I learned the tenants had been "taking the chill off" with the gas oven!
BTW, I'm eagerly looking forward to Jim Davis's class in Cincy later this month.

[viceman]

Glad to see people are doing it right. Good job.