What happens if you move your chimney to the back or middle?

[jcooke113]

I am having a problem and have been thinking to move my chimney to the middle or back of the oven? My oven door is directly under an outdoor covered area and I do not want to go with the 2 x 45's to extend chimney away and up from room line.

If I keep it in the front the chimney will be under my roof line

1. I dont want the fire risk
2. I dont want smoke sooting up underneath my covered outdoor area.

Has anyone moved an chimney to the back or middle of the oven? What was the outcome? Any other suggestions would be helpful, I am building a 39" oven, not enough space for 42" and 36" may be too small so going 1/2 way between.

Thanks,
John

[david s]

Re: What happens if you move your chimney to the back or middle?

The flue at the front and outside the oven chamber gives you the the best circulation of fire. It is basically a cross draft system and the design has proved itself over a few thousand years. It's disadvantage is that it's a bit smoky on start up until the flue heats up. I built my first oven with its flue in the centre of the dome. Ancient Roman kilns used this configuration. It worked extremely well, not smoky at start up at all because the flame wants to rush straight for the flue. There is far more heat lost out the flue though. Another advantage is that you don't have an entry to have to work past and the oven can therefore have a smaller footprint.for retained heat cooking you need a flue damper or cover to close off the flue. There are a number of small ovens in Pompeii like this. They are all small and we're probably in private homes. Being small the issue of fuel consumption becomes less of a problem. I've also tried building a couple of ovens with the flue between the oven door and the top of the dome. It actually proved to operate poorer than either the flue at the front or in the centre of the dome. If I were you I'd be going with the two 45 bends. I've built two like this and I think it's the best solution

[jcooke113]

Re: What happens if you move your chimney to the back or middle?

David,

Thanks for the info, I am trying to balance the overall look of the oven with the functional operation (need to keep the wife happy) I was going to build a house around the oven and that would hide the chimney and the 45's.

My wife really likes the way the oven dome look I care about functionality (i guess my brick work is better than I thought it would be). I have attached a photo of 6" damper designed for a pot belly that I found on ebay. I would go with an 8" if I go with the 45's but the 6" if I put the chimney on top of the oven.

I have followed the FB secs and will insulate with blanket and vermiculate/portland at 8:1. My goal is to fire on a Friday or Saturday night for Pizza/Calzone etc. and put a camp fire roast in the next day.

Do you think the combo of the 6" chimney with the damper will accomplish my overall goal.

Thanks again,
John

[david s]

Re: What happens if you move your chimney to the back or middle?

Here's a link to my first oven

http://www.fornobravo.com/forum/phot...ndex.php?n=511

If you are departing from the plans then there is no telling what the outcome will be.
Regarding the flue setup I spoke about, here is a pic of my solution. The oven is out of the weather and the flue does not go through the roof. I'm a believer of "form follows function"

[david s]

Re: What happens if you move your chimney to the back or middle?

Sorry, I didn't answer your other question re flue diam size. If your oven interior diam is 39" then you need an 8" rather than a 6" IMO. You can't really over flue a front flued oven, but you certainly can under flue it. You will have issues with smoke if you use a 6" flue.