Chimney problem

[hsumer]

Hi,

I am installing Pompeii Oven but i have a big problem.My outdoor kitchen is under my balcony & Teras.On plan,Chimney is going strait up.Is it possible to curve the chimney.

[dmun]

Re: Chimney problem

Code allows two thirty degree bends in your chimney. Your chimney has to terminate at least two feet above any structure within ten feet. Obviously if your chimney is going near your balcony, you are going to want the chimney at least high enough to avoid filling your house with smoke.

[hsumer]

Re: Chimney problem

I will have fireplace on balcony and pizza oven chimney will go through there 20 ft high from ground level.Only 30 degree is not enough to move chimney clear area.Is it possible to move chimney rear area on oven.

[brickie in oz]

Re: Chimney problem

Is it possible to move chimney rear area on oven.

You wont be able to get the oven hot enough as all the heat will just rush from the entry of the oven and out the flue at the rear.

[david s]

Re: Chimney problem

I've been chewing over a rear entry flue for a while as there is a huge advantage in removing the flue from the front so you don't have an entry to work past. Many downdraft kilns are arranged with their fuel/air intake on one side and their flues on the opposite side. The fuel enters rises and combusts and is then pulled down to exit the relatively small flue throat at floor level. The problem with a WFO is that at start up there is a fairly uncontrollable amount of fuel (wood) and i'm sure there would be big smoke problems until you reached about 200C and a good path would be developed. Such a configuration would achieve very high temps. and economical with fuel usage because it would effectively be a downdraft kiln, which are the most efficient. Perhaps if it were fired with gas for start up, then switch to wood, it would run really well. With more than 2000 years of oven evolution I'm sure someone has already tried this and I've not seen evidence of any, but I'd love to try it, although it could be a time wasting exercise.

[david s]

Re: Chimney problem

Hsumer,
Apologies, my ideas probably don't help you. Don't mess around with your oven design, you are probably better off trying to relocate it into a more suitable position and have the flue more vertical. CReating bends tightervthan 30 degrees is likely to compromise the effectiveness of the flue draw particularly at low temps and start up.

[brickie in oz]

Re: Chimney problem

With more than 200 years of oven evolution I'm sure some one has already tried this and I've not seen evidence of any, but I'd love to try it, although it could be a time wasting exercise.

So try it.
And report back

[david s]

Re: Chimney problem

Naah, just encourage someone else to have ago and report back.

[tony715]

Re: Chimney problem

more bends less draw. don't go that way. i've been in masonry my entire life and i can tell you you won't get the draw or the heat be a re-design of the location of the flu.

if i understand your problem correctly, and your worries of the terrace. why not cut through the terrace and run straight through?? thats what we do on house chimneys.

typically, we run two wythes of brick around the liner then the veneer. you could add an additional wythe of brick if concerns of heat. i am assuming you would be using all brick design.

don't know if that helps but its just another thought to chew on.

have a good day.

Tony
"owner of the two story WFO"

[dmun]

Re: Chimney problem

Now the Italians use sharp bends in the flues of their commercial ovens, so that the "pipe" can go from the center of the dome for aesthetic reasons. These are commercial ovens, so they seldom if ever cool down, so there is always some starter draft when you build a fire.

As far as venting the oven in the back, NO. Don't do it. It's been tried and it's a big failure. The circular path of the combustion gasses is critical to the success of the wood fired oven. Mess with this, and you miss the entire concept.

The thirty degree flue bends are in code because that's the maximum bend you can get a flue cleaning brush through. If your oven is that close to your house, you are no doubt pulling a permit, so that is non-negotiable.

[horrocks007]

Re: Chimney problem

Contact the manufacturer of your metal chimney pipe. They will end all speculation as they are the experts.

I used Metalfab for my wood stove, same quality as Simpson-Dura vent for much less cash. They explained to me that you are allowed 2 30 degree bends, but that also means you are allowed 2 30 degree bends that restore it to straight. This is what I have on my stove. I have a 15 foot+ run too. Draws fantastically and there is no smoke in the house.

Extra advice too-
If you are going to hide the chimney behind a veneer stone enclosure, you may want to look into buying galvanized class a venting pipe instead of stainless. it still has a stainless inner wall and 2" insulation, just a galvanized exterior. You only need stainless for areas that are exposed to the elements. - This advice will save you hundreds of $$$ a stove installation.

[hsumer]

Re: Chimney problem

Thank you for every body,
I am building shaft for chimney with AAC also i will build whole system with AAC (autoclave aerated concrete).I built my fireplace's chimney with AAC 3 years ago (in home) and decided build outside fireplace on my terrace and wood stove oven to outside kitchen on downstairs.I saw some people want to know AAC here too.I hope i will give them more information because my family is working with AAC since 1953 (from Europe).After I start build this wood oven project i found out chimney 5 feet away from edge.Downstair's clear Height is 8 feet (room is 11 feet but 3 feet beam height).Oven's chimney start point is around 5 feet so i have 3 feet height for 5 feet move to chimney.I am thinking chimney fan for more slope.What do you think?