I have a 25 year old wood-fired boiler with a 7" flue outlet. It is currently vented into a similarly sized flue of a 20 foot interior chimney, except for the 6 feet above the roof.. It has excellent draft but I am having a problem with creosote.
I would like to install a 5 1/2 X 5 !/2" stainless 316 rigid flue liner, surrounded by 1/2" of Super Wrap insulation, which will fit inside my existing clay flue liner.
Because the new liner would be the equivelent of a 6" liner and my boiler outlet is 7", will there be a problem with code. I don't anticipate any problem with draft. Otherwise, I will have to remove my existing clay flue liner.
Please advise.