Vincent Parkhurst wrote:Quick, and maybe stupid, question! I have a wood stove with a 6" stove pipe. Am I able to connect that with an 8" chimney? I found a complete 8" chimney that will save me hundreds of dollars if so!
Yes but, and it's a big but, the 8" chimney will want to run cold and this will work to reduce the draw. It will creosote up easier. You may bet smoking at the stove when lighting, difficulty lighting, smoke if you run the kitchen and bathroom exhaust fan together, or the clothes drier or if someone opens a window upstairs etc. We are off grid and our 8" chimney system is on an 8" outlet stove. We light the fire in September and it burns steady through March. We also have a 6"outlet stove in the shop and have experimented with chimneys. We know things about chimneys. And ours is perfected - for us, in our application.
Use the math of pi-r-squared to see the huge volume difference for the 8" and you will see you will be pumping a lot more air and heat up there. Install a baffle in the 8" near the stove and this will help butbwill not prevent things gumming up.
If it is mostly insulated pipe that will help. It is commonly only gets down into the -30s here now, rarely -40 and never the -60s of 40 years ago so trust me when I say an 8" chimney needs a good amount of heat flowing up it in the winter for it to work well though careful installation design makes a world of difference.
You will want to look at the idea of a short hot burn once a day to help the pipe stay cleaner.
Expect frequent cleanings.
And you may have to fake up an adapter for single wall pipe to the inside of the double wall. Or not. Having a sheet metal crimping tool and a riveter will help with this. You can use off the shelf duravent type single wall bits as raw material. Your insurance company might freak out.