I bring cold air in from a hole i cut in the air duct. Then i have the exhaust going threw a carbon filter and straight into the attic. The air is sent all the way to the top of my attic so if any smell did make it threw it would be sucked out the temperature exhaust fans in my attic.
I really got lucky with my set up and im sure everyoneâ??s is going to be a lot different. With a little creative thinking and trial and error you should figure it out.