Venting Propane

[gonyo]

So I've got a quick question for the people here. I just bought a mr heater big maxx 80000 btu have it converted to propane and i'm installing it in my garage. I already have an 8 inch metalbestos about 6 or 8 feet can't remember, running through my roof from an old woodstove i had in my shop before. can i just vent the propane heater through that with an 4" to 8" adapter or will i have freezing issues from all the moisture the propane will put out. I've looked through the manuel and maybe i just don't know what to look for but i cant seem to find an answer. I'm in the interior of alaska and it gets pretty chilly in the winter. -60F
Thanks for any help you may offer.

 

[Jackfre]

You will be better off if you run probably a 4" b-vent inside the Metalbestos. I have the tables if you tell me how long the vent connector is and how high the stack is. Also, is this fan assist or natural draft?

 

[gonyo]

the metalbestos section is 6 feet and the heater will hang right from the ceiling so another 2 foot down from there will be all the. it isnt fan assisted.

 

[Jackfre]

If you run it all in B vent you can use 4”. Max input on natural draft 8’ high with 0’ vent connector is 94kbtu