My old Encore had the ability to change from 6in flue to an 8in flue depending on the application. If the 6in flue was used the front doors were not to be opened for an open fireplace setting. My dad has a VC Defiant Encore with just the 8in flue. Can I neck it down to 6in as long as I neck it down close to the stove? I have heard of issues running 8in pipe to a 6in flue and the gases can bottle neck trying to get out and ignite within the pipe. Thanks
