As long as one does not rob all the air flow and create a cold spot two stacks should be okay.....but I am far from the one with the answers on this so don't take my word as gospelTTsOldIron wrote: ↑January 16th, 2019, 11:23 amSo I got the end capped off and am planning on using a 6” pipe I have for my chimney but I am planning on making it a dual exhaust partly so the chimney isn’t so high and also for the cool factor. Is there any reason that the dual chimneys would be a problem in performance?