If you have enough CFM's pushing air towards the stack I'm thinking you should be good
tinytoon Reviewed by tinytoon on . Ventilation through furnace/hotwater heater stack? The only feasible way I could imagine running my duct lines to keep the heat and smell out of my grow room would be to run the duct tto the furnace/hot water heater stack going up three floors to the roof. Has anyone vented their room this way? Would i need a back flow vent to keep the smell from winding back up in my room? Rating: 5