Forno Bravo Forum: The Wood-Fired Oven Community

Forno Bravo Forum: The Wood-Fired Oven Community (http://www.fornobravo.com/forum/)
-   Design Styles, Chimneys and Finish (http://www.fornobravo.com/forum/f9/)
-   -   Chimney Draft Issue (http://www.fornobravo.com/forum/f9/chimney-draft-issue-18366.html)

thefirepizzacompany 09-16-2012 03:13 PM

Chimney Draft Issue
 
Just installed a 47" Modular oven in a trailer. The Door opening is 22"x 13" to the top of the arch. If I do the math its 286 square inch opening minus whatever the arch takes up. I used a 36" tall 6" insulated chimney. From what I gather the chimney should be about 10-15% of the opening 6" chimney is 28.27 square inches.

With all that said I am having issues with the Draft. I have a good deal of smoke coming out of the front. Mind you I am burning a small fire at the moment, still curing right now. I also do not have a rain cap on so I'm not sure if the wind is causing issues. Any ideas if when the oven runs hotter the heat will help increase the draft or if I should add another foot of chimney on??

david s 09-17-2012 02:25 PM

Re: Chimney Draft Issue
 
1. New, wet ovens are notoriously smokey
2. A 6" pipe is way too small IMO for a 47" oven.The 10% rule might be OK for draw once the oven is pretty hot, but it is inadequate at start up, when you are trying to pull the flame sideways. Should use 15% of oven opening as a min IMO.
3. You could increase the draft by adding more height, but as your oven is mobile you'll need to make it removable.

Suggest you keep firing to see if it's still a problem after about 10 pizza temp fires.
Also try only minimal addition of fuel at start up.

Tscarborough 09-17-2012 02:50 PM

Re: Chimney Draft Issue
 
Light a small fire directly under the flue to warm it up first.

ikold 10-28-2012 10:57 AM

Re: Chimney Draft Issue
 
Need to get the flu hot to create the vacuum. Also our oven when we were seasoning it was (wet) smoky. But its definately drawing great now. Our flu though is substantially wider.


When starting a fire in a seasoned oven do the majority of you create a "rager" in there. I notice that with the fires we are building we don't burn off all the soot in the dome. We definately burn it off in the center where we start the fire and to whatever side we push the coals to, but there is portion of the oven that still has black soot on the ceiling. Is this good/normal?


All times are GMT -7. The time now is 10:19 AM.

Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
2006/10 Forno Bravo, LLC