Wife and I are having a new home built, Per Idaho regulations an outside air kit is required for solid fuel appliances installed in new construction. The problem i am facing is the sizing of the OAK intake pipe, the manifold that takes the place of the lower heat shield has an outlet diameter of four inches, however because the wall behind the stove where the stove will sit is of 2X4 construction we are limited to a 3 inch pipe. Will reducing the size of this intake via an adapter compromise the performance of the OAK? Going straight down with the pipe is not an option as the stove will be sitting on a custom granite slab and Id rather not drill a four inch hole in it. My current plan is to come off the manifold with a four inch 90 then straight into the wall utilizing a reducer to hook up to the three inch pipe that extends down into the crawlspace (vented crawlspace) any insight would be great!
