All fuel pipe question

[briduhunt]

I have achance to get for free 8" all fuel pipe and fittings. The evaporator that I have (2x6 Leader) has a 6" vent. My thought was to install the 8" pipe down thru into my sugar house about 2' then sleve a 6" pipe up and out the top of the 8". The 8" all fuel pipe will be my insulator and the vent will actuall be ran from my rig to up and out the roof. I would run the 8" and the 6" vent pipe at least 5 to 6' above my roof. Does anyone think this would draft properly? (my height from the floor to the roof is 11'). I have priced the 6" all fuel pipe and just the two sections of pipe and flashing comes to around $230.00 and that is using my HVAC connections for good pricing. The season is fast approaching and my cash flow is getting low just as fast if not faster. I want the system to vent properly and I also want the protection of the all fuel pipe. Any input would be greatly appreciated.
Thanks

[WF MASON]

Is 'all fuel' pipe, double wall metalbestos pipe ? Is the evaporator oil fired ?
Either way I'd think the smoke would go up it.

[C.Wilcox]

briduhunt,

My woodstove in the house uses about 15+ feet of 6" diameter triple wall insulated pipe stacked on top of 6 feet of single wall pipe and it drafts just fine once you get a good hot fire going. I would assume your set up will work just as well, but if you live in an area with that has planning and zoning requirements I'd check with your local inspector to make sure before you get started. The inspector in my area required a fire shield where the insulated pipe passed through the second floor and then another where it passed through the roof line. He also required one inch of clearance minimum around the shield to any combustible surface. Overly cautious perhaps, but he didn't want my house to burn down and neither did I. In addition, I would make sure that whatever chimney cap you use is larger in diameter than the 8" collar pipe so that you don't get snow/rain in the space between the outside of the 6" and the inside of the 8". That could lead to a cold spot which could lead to creosote formation. Just my humble opinion anyway.