Setting up a grow room. It is in my basement. I live in Michigan where it is freezing in winter, so wondering how to set this up, I have a basement window on the top near the ceiling. Just wondering if I can pull air from that and exhaust into my dryer vent, or in the winter, exhaust into my home to save on bills. I've read that passive air flow comes in from the bottom, and you exhaust from the top. How can I set this up so it works for all seasons? I have 2 1000 w lights. My room will be approx 60sf. approx 5.5 x 12. (At an angle, it goes to 7 x 12 on one side) Using c.a.p ebb n flow 12 pot plus 6.. Trying to decide whether to buy 6" or 8" air cooled reflectors, and fans. Need advice on how to ventilate and filter the air. Do I run through both lights or use 1 fan for each light? Can I use outside air without worrying about the temperature change and exploding the lamp?

I was wondering the same thing.

i would go filter light,light, then canfan w/440cfm or greater rating try to limit bends in the ducting cause youll lose flow exaust out window in summer and into house in winter. the intake should come from inside the house so the airs not 2 cold p.s. ur dryer vent is to small fer exaust and ur intake should b on oppisite side of room than ur exaust to suck fresh air across room

I'm setting up a similar basement grow, Hey liberty, do you use 8" ducting, 8" air cooled reflector, 8" fan? I read somewhere that if you used a smaller duct (like 6" for an 8" fan, the fan has more pull.

Pull air in from outside but your dryer vent is just too small to be useful. I would recommend venting to outside or into the house. If you setup a y-split with dampers you could direct exhaust into the house in winter to heat the house and outside in the summer (you don't want more hot air in a hot house.)

How high is it? With 2k of lights I would recommend at least a 650 cfm fan just for the lights (1 CFM per 3 watts is a good ballpark).

Me too (24 pot).

8" is mo betta.

Depends. If the ducting is fairly straight and you use a high enough cfm fan running in series should be fine. If you have a u-turn or lots or 90 degree turns increase the cfm to compensate or run separate ventilation for each light.

Not positive (Cali boy here) but i think it would be ok.

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The CFM remains the same but when you constrict the ducting the velocity increases (and causes the fan to work harder.)

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Thanks so much for your help. I have decided to buy the 8" elicent 200B fan with 636 cfm. with the variable speed control. Now I just need to find the correct filter. When I look at filters, they say the 8" is good for huge rooms. Can you recommend what filter to buy? Not sure where it goes either, have been told to put it before lights or after the fan. So you are saying an 8" filter is easier on the fan?

Here is my proposed setup...cool air intake is from under the house ducted down at 45 degrees to bottom of grow room to 8" inlet (passive). Ducted exhaust will run from near this inlet into the 2 1000 w air cooled hoods (or cool tubes?) and discharge to outside the room to elicent fan and then into filter. Or do I start the ducting w/filter, then lights, then fan? Workable?