1. fans require cooler fresh air to draw from and a place for the hot stale air to exhaust to.

cfm listed above, one exhaust fan is usually enough in a sealed system
Dutch Pimp Reviewed by Dutch Pimp on . Fans - Not just blowing hot air! I apologize in advance for the length of this post, but you clicked it - you must be interested! There have been many, many topics posted here that are basically the same questions - can I use this fan? Will this fan work? Which fan should I use? What's the best fan? Hopefully I can get all the information together here in one place and finally "blow the lid off" this whole fan thing. Please note - I am not talking about sealed rooms with CO2 enrichment. These setups will require very Rating: 5