I have a grow room 8' x 14' and 8' high. Using 1000 watt hps and bringing in fresh air with an a/c. What size vent fan should I be looking for? How many cfm? Thanks....

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Lagwag

Ok heres the deal if you are using ac will not have to vent out any air. All you willhave to do is keep the air circulating with a charcoalcarbon filter within the room. A fan should be able to replenish the rooms air within 5 minutes.

8 x 14 x 8= 896

896 / 449 (lets use this as the recommended CFM fan for your room) = 1.9

So a 449cfm fan will replenish or recirculate the air within a room with 1.9 minutes.

Since you have acin the room I suggest you get an aircooled reflector to exhaust the heat from outof the room as well.

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In the Sun
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