Expert: James Ball - 6/18/2011

Question
I have a 20 year old wood burning fireplace insert with a Martin industry 10" flue. The label on flue says compatible with E series triple wall Thermosyphoning or S series two wall. I am putting in a new custom built wood burning firebox that is quite large (58" long, 22" tall and 22" deep and the manufacturers/designers say that I should put two 10" class A flues. I would like to save some money as it is quite expensive and am wondering if my old Martin Industry  flue classifies as Class A so that I might only have to purchase one new flue system instead of two. It is a two story house

Answer
Welcome Brian, you have to follow the manufactures installation instructions of the new unit, and check with your local building department, these units are tested using a certain pipe, giving it a "Clearance to combustibles" that if you change can cause a fire and that might void your home owners insurance. this is not a place to cut conners putting your home and families safety at risk
James