Barometric damper question.

[HJsimpson]

Ok im ready to throw this thing out the door. I have it set at -.03 with a manometer but it is cooling down the flue way to much. It is 500 degrees before and 250 less the 18" after damper so needless to say im having a creosote problem. My furnace has a draft inducer on a thermostat so this is required by the manual. So here is my questions.
#1
Should i close damper once a day when i burn hot to help clean the pipes?
#2
Since the draft inducer is only being used after a reload could i get away with a key damper?
I have 31 feet of chimney so i have a very strong draft and i really like the new furnace but this problem with the barometric damper is giving me fits.

 

[laynes69]

I don't think the baro is the problem. As long as the furnace is burning the smoke, there should be little buildup in the flue. You cannot use a key damper. If the combustion blower would operate, it could pressurize the firebox causing combustion products to enter the home. How much creosote is there? I would expect more chimney maintenance on a pre EPA unit. Try smaller hotter fires, or increase the flue to .04" to allow more heat up the chimney. If you eliminate the baro you could cause damage from a overfire.

 

[Humplumb]

Just a thought here,hows moisture content of wood i kinda had the same problem fire stove leave damper open stack temps 350 -400 no problem.As soon
as closed damper and started gasifying temps would drop to 275 280 .went and got some good dry wood temps went back to 350 375 np no creosote again just a thought.good luck!