We have an unknown vintage Tempwood which came with our 1400 sq ft house when we bought it a year ago. We are wood heat only (4-4.5 cords of hardwood per year). The Tempwood is on a 6" stove pipe in a central chimney where its clay flue liner has collapsed into shards at the bottom, meaning the pipe can't ever be removed or replaced without disassembling the entire chimney from inside the house (way too expensive, not an option). Our mason, who is currently rebuilding the top of the chimney to stop water leakage, told us that the creosote build up in the stove pipe was extreme for one year of use (it gets professionally cleaned once a year). His opinion is that the 6" pipe is too small for a proper draft on the Tempwood, and thus we are getting dangerous creosote build up with our heavy use. He thinks we should put the wood stove into our fireplace flue (12" square clay flue, totally intact), or into a basement flue (7.5" square clay flue, totally intact). He thinks a wood stove wouldn't need a pipe inside either of the other two clay flues, and would produce less creosote. I've been reading on here for a while, but am a total newbie to wood stoves. From my reading, a 6" pipe is standard for modern catalytic stoves, but is it sized right for an '80s Tempwood? Would putting the Tempwood (or another, bigger stove) onto a 12" fireplace flue or a 7.5" basement flue help the creosote build up, or increase it due to slower drafting? My thoughts prior to the mason's suggestion was that our creosote build up could be because we have to smolder (shut down the vents) the stove over night and during the work day so that we still have embers when we wake/return and can restart the stove quickly, so we've only been full vents-open burning for about 5 hours in the evening and 1 hour in the morning most days. I had been thinking that a bigger stove would allow us to keep the air vents open over night and during the work day without having the stove go totally cold, maybe a mid Moe or Mama Bear or something similar. But, now knowing that we can't change the stove pipe, and that the flue liner is a mess, I'm kind of at a loss---help a newbie out?