Welcome! Here are the website rules, as well as some tips for using this forum.
Need to contact us? Visit https://heatinghelp.com/contact-us/.
Click here to Find a Contractor in your area.

Using chimney as chase for 95% vent?

hot_rod Member Posts: 22,121
if you have a straight shot. Make sure you have good support at top or bottom so the vent pipe weight is not on the boiler connections. Use the excat pipe that the manufacturer reccomends schedule 40PVC, not the cell core stuff.

Some brands require stainless vent pipe.

hot rod
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream


  • Saggs
    Saggs Member Posts: 174

    I'm installing a 95% LP furnace in an old farmhouse w/ metal roofs. Snow fall and accumulation makes thru the sill venting almost impossible. I was thinking of using an empty interior chimney as a chase for the PVC exhaust and maybe the intake pipes. All of the chimeny is in heated space except for last 5ft. Do you think there may be a problem w/ freezing or frosting condensate inside pipe or too long a run? Total lenght is about 30ft. Temps in VT may get to -20 in winter.. Any thoughts? thx
  • Charles G.
    Charles G. Member Posts: 113

    As always, follow the I&O manual for the unit. You may need to insulate the pipe in the chimney.
This discussion has been closed.