Offset flue

[david s]

I'm currently finishing two ovens with offset flues. I believe there are some advantages doing it this way. Firstly the oven can be located under cover, the mouth certainly which is the most important part to keep dry. Secondly it negates the problems of penetrating the roof, namely sealing problems, having to use a double flue and roof corrosion around where the flue penetrates from corrosive emissions. The drawback is the look of the thing, I'm undecided about that, it does look a bit "industrial" The extra bends also create some extra cost and installation time.

[v12spirit]

Re: Offset flue

I have an inherent problem in my indoor build; the flue exits right behind the oven. I had two choices, either to make the offset like yours which will make the whole thing look "industrial", or to make the flue more aggressive with upright angles so it can be flush with both the oven enclosure top and the wall behind the oven. I believe the second choice will result in a hesitant airflow and will make the oven "breath" inside the whole kitchen. I installed a ventilating fan on the flue exit in order to force the exhausts to go into the flue but am not sure the fan will be always available (The electricity goes frequently being exposed to projectiles ) I'm no longer sure what is best to do.

[cobblerdave]

Re: Offset flue

Gday
If you were to use 2x45 degree bends instead of 1x 90 degree bend to get to the horizontal, then 2x 45 degree bends to get back to the vertical, it would achieve a couple of things.
It would make the 90 degrees transition a lot longer and more gradual and make the smoke passage a lot smoother. It will take up more room in the transition making the horizontal section a lot smaller.
I'm no expert by any means but smokes doesn't like to go sideways or horizontal it wants to go up so the more time spent in those 45 degree bends the easy the flow I'm thinking.
Regards dave

[david s]

Re: Offset flue

I have an inherent problem in my indoor build; the flue exits right behind the oven. I had two choices, either to make the offset like yours which will make the whole thing look "industrial", or to make the flue more aggressive with upright angles so it can be flush with both the oven enclosure top and the wall behind the oven. I believe the second choice will result in a hesitant airflow and will make the oven "breath" inside the whole kitchen. I installed a ventilating fan on the flue exit in order to force the exhausts to go into the flue but am not sure the fan will be always available (The electricity goes frequently being exposed to projectiles ) I'm no longer sure what is best to do.

A horizontal flue is a no no. Make it go up at an angle otherwise you will be depending on your exhaust fan to do the draw.

[v12spirit]

Re: Offset flue

Thanks Dave and david
Your inputs inspired me to use a kind of flexible flue liner like the one below, I think it will enable me better smooth-en the draw, while trying to keep pace with the enclosures and hide the flue. If I find one I will use it.

[jcooke113]

Re: Offset flue

I am having the same problem and have been thinking to move my chimney to the middle or back of the oven?

If I keep it in the front the chimney will be under my roof line and 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?
Thanks,
John