Chimney Questions(s)

[thebadger]

Gang,

Planning this build for next spring but still planning ahead.

Building the 36" - the FB plans say a 6 inch chimeny is okay - just wanted to confirm given the info below.

I'm building the oven under/near my pergola so the chimney has to extend 2-3 feet above that (and the pergola is quite tall). I'm thinking I'll need an 8-10 foot chimney - planning on a duratech double wall system.

Questions:
Any issues with the chimney being that tall? (I should be able to provide support half way up)
Will the 6 inch dia still be okay?

Thanks in advance
Dick

[wlively]

Tall is OK, in fact the taller the better the draw.

[RTflorida]

I too used the 6". In my opinion it works perfectly...of course, I don't have anything to compare it to.
I can say it draws very well with very little smoke in the face, and that is only on start up. I've found fire building to be an art; the right combination of DRY materials, placed on the fire at the right time, leads to nearly zero smoke.

[Les]

I need to insert a question as well on this subject. My opening is 6 x 13 inches, I can buy a flue that will fit - I was thinking I would go vertical 18 - 24 inches. Do I need to taper the flue as I ascend, or would the gasses draw just going straight up ? This part of physics is outside of my pay scale.

Les...

[nissanneill]

Hi Dick,
I built a 40"Pompeii and used 3 sections of 8" flue. See:

http://www.fornobravo.com/forum/21/n...-a-2119-2.html (Neill's Pompeii #10)
I get absolutely no smoke out the front of the oven face as the vent and chimney draws exceptionally well.
I have just pushed them together and not even rivetted nor screwed them together and have had no problems what so ever.
I agree with RT and there is a science in setting a fire that produces the least amount of smoke. All dry wood, plenty of kindling to get that initial heat and no smoke. I made 2 stands that hold one end of the wood higher and allows the air to get in aqnd under the flames and works a trteat. Much quicker and hotter fires. I also found that you need to almost constantly tend the fire until you load the dry split logs or hard wood which wil take time to burn down to the coals which I then spread around the hearth. When almost ready to cook pizzas, I push the coals to the back and put 2 or 3 fresh aplit hardwood logs on which catch almost instantly, sweep the hearth and cook away.

Neill