Budley Doright
Well-Known Member
LOL I know enough about duct design just to be dangerous 
, I'm a ref. Mechanic and the duct is already there when I arrive lol. A 6" exhaust @ 340 CFM will create a fairly big negative if using same size passive intake as it has to pull the air in. The whole concept of venting a room is based on creating a slight negative for odour control, and the more tricky part, temp control, kind of the opposite of a clean room. The only accurate method would be an intake and exhaust fan working together with balancing dampers. How big is the room, and is the system noisey now? 350 CFM through a 6" pipe is going to exhaust the air at about 1750 ofpm which is huge, should try for around 700-800 fpm for noise. Your pulling huge amounts of air unless it's a big room. I pull 200 max from a 8x8x7.5 with no odour issues and lights are ducted (not sealed). Sorry, just vapped and dabbed, rambling lol.
, I'm a ref. Mechanic and the duct is already there when I arrive lol. A 6" exhaust @ 340 CFM will create a fairly big negative if using same size passive intake as it has to pull the air in. The whole concept of venting a room is based on creating a slight negative for odour control, and the more tricky part, temp control, kind of the opposite of a clean room. The only accurate method would be an intake and exhaust fan working together with balancing dampers. How big is the room, and is the system noisey now? 350 CFM through a 6" pipe is going to exhaust the air at about 1750 ofpm which is huge, should try for around 700-800 fpm for noise. Your pulling huge amounts of air unless it's a big room. I pull 200 max from a 8x8x7.5 with no odour issues and lights are ducted (not sealed). Sorry, just vapped and dabbed, rambling lol.
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