Hi there, I am new around here, but the wealth of information is great. After years and years and then some more years of faithful service, our 40 year old 10 scallop Earth Stove is just plain done and we have decided to replace it with a new Drolet Austral. The old stove pipe and Class A chimney was 8" and the new one is 6". Our Current chimney is older, but we had it inspected last year and they said it looked good, and it still cleans up very well. My questions. ultimately lies in what to do from here. My local stove dealer is recommending just installing new 6 inch single or double wall stove pipe all the way up through the existing chimney almost as a chimney liner. Is this a good way to go? Obviously this would draft well, but is it up to code? Would it be better to use an adapter to upsize to 8" at the ceiling support box? Draft will likely never be a problem as the entire pipe/Chimney is 22 feet straight up, the first 12 feet inside the house. Thoughts?