this is what i've found:
however, the next question is what type of fittings do i need to terminate both ends of the chimney.
on the inside end, i will need one 6" elbow at the very bottom, for the boiler, and a 6x6x3" tee right above it for the 3" water heater duct. also, will i need anything on the chimney top?
i saw they have many different types of fittings on that web site and i am unsure as to which to get.
also, for the duct inside the house for in between the appliances and the chimney entry, can i just use regular hard duct from home depot? i noticed that the existing 6" duct for the boiler in the basement has firmer joints than regular crimped/taped ones for like a dryer vent and they have screws.