Vent landing size

[rlf5]

Is there a minimum vent landing size for a 42" oven? Currently mine is a trapeziod with dimensions of 50cm on the top and sides, and 57 on bottom. Is this size sufficient? Also, when I make the arch, how far from the oven opening should the chimney opening be? I plan on using one of the DuraTech chimney's from FornoBravo. Thanks!

[wlively]

I do not know if there is a minimum, I would think what ever is comfortable, that is what I did. Mine is 12 inches deep, 19 inches wide at oven mouth and 21 inches wide at the end. I don't remember the exact dimensions of the vent opeing in the arch, but is somewhere in the neighborhood of 4" X 14". You can see a picture on my oven post for reference. The opening was centered in the vent arch to make construction easier. I poured a molded vent transition to go to an 8" duravent chimney.

My vent works well and I only get a very very small amount of smoke when my fire is just started and if it smoking heavily. So, the thing I would do different is make my opeing as wide as possible, going to the very edge of the arch, since the smoke that occasionally escapes is going past the closed side of the vent and does not make it into my swirling vortex of smoke. It is wild to see the smoke coming forward, then turn a 180 and go up the vent. I think making the vent opening wider would have helped.

[rlf5]

Thanks for the advice about the width. Looks like your vent opening beings about 1/2 brick length from the oven opening. Does that sound right? Does it make a difference how far from the opening the vent is?

[wlively]

Yeah, that is about right. I would think that closer is better, because you keep more heat in the air. The more heat the faster it wants to rise and the hotter you keep the chimney, which should help keep the soot build-up down.