CountZ

Hi all,

Built myself a grow box and was wondering about the fan setup.

Considering the fact that the box is not air tight, does it actually matter
if I user the fan to draw air out of the box or into the box ?

Currently I'm using it to blow air into the box, directly on the glass of the HPS lamp I have in there to cool it, however since everywhere I read people only use fans as exhausts it made me wonder...

Cheers !

Mr Green

Yo countz, welcome to hc.com

Just how big of a box do you have?? What kind of lights do you got and how many plants?

If you box is not air-tight, you might end up with some light leeks.

If you do have a fan and can place it on the top of your box for exhaust, make a hole at the bottom and the fan will suck in fresh air while pushing the hot air out.

good luck........wish I was grow'n too

mr g

swarfare

Wouldn't it work in the converse just as well? My setup's got some holes near the bottom of the box, with a fan pointed right at it blowing air in. Then there's a hole on the lid of the box (no light leak issues as it's in a dark room anyway) that should then vent air out that way, right?

aeroskunk

well, if you have an exhaust instead of an intake, then your directly sucking the hot air out, and pulling room temperature air in .. reverse that, and your pushing room temp air in, and forcing the hot air to rise or escape, which may take longer than directly sucking the hot air out, as you're kind of going against the flow of things.


in this scenario, you should try sucking the hot air out (exhaust), which would result in a cooler grow space as long as the outside room where the fresh air's being drawn from is conditioned. and the hot air you do vent, needs to be vented to a spot where it wont recirculate into the intakes line of fire, try venting to a different area completely, with a dryer hose or the like.

if you've got both intake and exhaust fans, the air exchange is rapid and consistent, and can be controlled on a climate controller, taking only minutes to adjust the temperature. this is the best option, IMO.

harrad

If odor from your chamber is a problem, you want the fan to be on the exaust. Negative chamber pressure means that air will be sucked in at the leaks, not blown out. Peace! Harrad.

CountZ

Hey,
Thanks everybody for all your input.
The box does have light leaking out of it, however since I'm no carpenter
and I built it myself it makes sense
The box is about 4x2x2
I have a 70w hps and a 48w florecent and 7 plants I'm starting for scrog.
I put in 2 small fans (taken from computers). One is at mid hight pushing air in and the other is neer the top pulling air out.

Thanks again all !!!