Quote Originally Posted by GaGrown
You are soooo right! Take a Hydrofarm 465 or a 265 cfm fan,for instance.. Both these type fans are what they refer to as active air blowers. They are meant to be used inside the grow area and blown out of the room.A furnace duct fan keeps itself cool by being inside the cabinet. If you use an active air blower then it is advised that you not use it as an exhaust fan. You have 3 ways that air can be used to serve your needs.

Passive air
Exhaust air
Active air

Each one has it's own application.Passive air will occur when used with an exhaust or an active air blower/fan. Exhaust is where the fan is placed on the outside of the grow area.

Ga Grown!

I should mention this since this thread is about ventilation... If an active air blower is used other than by instructions,you could risk a fire.

If you pull exhaust air through an active air blower your heating the motor and damaging the bearings.If you hook it up right and use it the way it is designed to be used it will serve you well.If not? They get wobbly and noisey.A 1000 watter is an active air blowers worst enemy!! Be safe not sorry!

Ga Grown!