I try not to post while high, but I thought I'd throw this out there anyway .... when designing my cabinet, I seem to recall reading somewhere that the intake should be at least slightly larger than your exhaust, particularly if you are not using a fan to pull the air back into the cabinet (passive air flow?). This also helps replenish CO2 levels.

So, I don't think it's a problem of not enough air being pulled 'out' of the room, but not enough being pulled 'in'. I have been known to have bouts of dyslexia, especially when high, so I would research this a bit.

In any event, I wish you luck finding a resolution! I know all too well how bad heat can be.
joe-grow Reviewed by joe-grow on . AAAARRGGHH!!! I DONT UNDERSTAND! I've just completed one grow in a 1.2m * 1.8m closet, its 3m high too. I had to keep the door open, and with just a dinky little fan blowing on them from the doorway, they managed to stay at about 27C all the way, under a 400w HPS. For this grow, I decided to do things a little better. I smacked out a 12 cm round exhaust hole at about eye level and a 10cm intake at roughly floor level. I inserted the 12cm flex ducting, pulled it all straight and inserted it into my brand new fan which I've Rating: 5