I'm updating an exhaust pipe on my furnace.
Currently I have 4" steel exhaust pipe coming from my DUKANE MPGA075B3 (75.000 BTUs) (AFUE% = 80%)
I would like to update it to "Thermoplastic Pipe" because it require a 0 clearance to combustion material.
Few questions: Do I have to use a 4" pipe or I can use a 3" pipe?
Can this pipe handle the amount of heat my furnace producing?
Thank you.