Chimney design ?

[boazts]

Hi, all.

Now that I finished the foundations and the base I am ready to start with the real work...
I'm designing my oven and wanted to learn about chimney design.
how high should it be?
where should it be located? (how far from the opening?)
what should be the internal diameter?

Please help.

My oven will be (if everything goes well...):
dome style.
floor internal diameter 70cm (27.5 inch)
internal height 30 cm (11.8 inch)

Boaz.

[Neil2]

Re: Chimney design ?

First, there are two approaches to flue/vent design.
1. Sized so that all the smoke, even during start up, goes up the vent.
2. Sized so that the fumes/smoke during cooking go up the flue (and not in your face) but the initial start up smoke may go out the front of the oven

In my opinion, you are never going to guarantee that #1 will never happen. You may get a load of particularity smokey fuel. I would go with #2. For a 40 inch elliptical pompey if find my 7 inch diameter by 18 inch high vent perfectly adequate. Mine is immediately (1 inch or so) outside the oven opening.

[boazts]

Re: Chimney design ?

Thanks for that info.
another question, please.
is your chimney isolated? all the way up?

Boaz.

[dmun]

Re: Chimney design ?

another question, please. is your chimney isolated? all the way up?

Do you mean insulated? If you use a commercial chimney system, yes, they are insulated. If you build a traditional masonry chimney, there is only an airspace between the flue tile and the surrounding masonry. Many of us insulated the entry and the transition to the flue, to prevent heat loss, but it's not at all mandatory.

[Neil2]

Re: Chimney design ?

"is your chimney isolated? all the way up?"

Yes. Insulated (double wall) all the way up.