Overdraft Questions.

[HJsimpson]

Im almost finished installing 32 feet of 6 inch stainless class A chimney on the north side of my house. My concern is it is just an open field and that is where we get most of our wind from
The original chimney was a 7 X 11 clay lined block which drafted very hard in the wind and since i dropped in size im thinking it may be worse. Anyone use the cap that turns with the wind which i was told would help with the draft? I cant use a key damper with a BDR so thats out of the question.
The new chimney is also installed on the outside of the house and not sure if im going to be able to build a chase around it this year or not.
Thanks everyone.

 

[laynes69]

You will find the 6" will draft better on a lower fire. I had the same setup with a 7x11 then lined with a 5.5" rigid liner. That barometric damper will keep a constant draft for the furnace. We had some strong winds yesterday and our firebox remained untouched. Your furnace requires a flue setting of .03" of water verified with a manometer. So your draft will be much lower than what the 7x11 or 6" chimney would produce. A word of advise, keep an eye on deposits and clean when needed. If everything is operating correctly the baro should remain clean. If it gets creosote on it, clean and reset to the recommended draft.

 

[Backwoods Savage]

Never liked the barometric dampers. You should definitely notice better drafting with the 6" chimney. I would not worry about it unless you see a problem, which I highly doubt you will. It should be ideal.

 

[laynes69]

I'm not a big fan of baros either. The difference between a stove and furnace is the temperature in the home controls the furnace. So at anytime, the damper could open. We burn in a EPA certified wood furnace. I have had a half dozen fires or so this season. When the furnace is burning, there's no smoke. Without smoke, there's little chance for creosote. If I had a stove and had 100% control of the intakes I wouldn't run a baro. I did try a manual damper, but once again with an automatic draft it produced poor results. By me running a baro I am guaranteed to have the proper draft needed for the furnace. There's a fan/limit control that closes the damper if the furnace exceeds 250*f in the plenum. So the risk for an overfire is reduced or eliminated. They do reduce internal temps, but running a stainless insulated liner the chances for condensation are reduced. They are recommended on gasification boilers and increase efficiency. We have a 32' chimney, so for us it's one of the few ways to keep draft in line.

 

[HJsimpson]

Thanks guys.
Im never was a fan of the baros either but with the furnace in the basement both old and new i found out pretty quick they are needed with tall chimneys.
Im trying to get the chase built this year to keep flue warmer but im up to $4500.00 so far with install so the shoe string budget is starting to fray pretty bad. I know ill be cleaning a little more often this year until i get used to the new setup but thats part of the fun.