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4 x 2 x 4 Tent Help with Heat


New Member
Ok gang I'm a newbie just starting out and have problems with HEAT inside of 4 x 2 x 4 tent with T5 4-bulb fixture and i can not for the life of me get this tent temperature under control.
Day one set tent up hung T5, put two 6 inch clip fans in zipped her shut and within less than an hour it was 102F inside of tent so my first step was to open back and 2 side passive air vents but this did nothing. So next day I went and bought 2, 6 inch inline duct fans 250 cfm and put 1 of the fans in the side of tent as exhaust sucking air out of tent while leaving bottom flaps wide open hoping that the negative pressure would be enough...This also didn't work as temps were still at 88F & 51 RH but note that I was exhausting the air back into the same room as tent is in so the tent passive air vents at the bottom were sucking in same air that i was pushing into room but I have a widow wide open at all times so I thought it would make the difference.. Wrong!
The room is a small bedroom 10 x 10 with one window that i leave open 24/7 through the summer and normal temps inside of room are 81F during the day and might dip as low as 60F at night...My question would be do you think it would help to add 6 inch 250 cfm inline duct fan to force air inside of tent as well as exhaust it the same?
Any help , advice would be appreciated. Thanks

CO Finest

Plant of the Month: May 2014 - Member of the Month: July 2014
Have a fan on top of tent pulling hot air out. Heat always raise up. Put a six in tube on it and have it blow the hot out of window.Now on the bottom of tent put fan blowing in. On the fan on bottom blowing in add ducking and try to get it pulling cooler air from outside of room witch would be hallway or whatever. Pulling from out side not to good for a few reasons. One is if anyone grows a male plant out side 20 miles from you,that can get to your females and knock them up. Two is the temps change to much so you will have temps all over the place witch can cause your plants to stretch and in flower time will cut your yield back. Three If it gets 65 or lower a few nights and your tent drops to low, your plants will turn purple witch looks cool but your thc and cbd will suck and be very low. I wish you the best


New Member
Well thankfully I'm just at the beginning of veg so I have time to tweek this setup before I get to far into cycle but I'm telling you it's been a pain in my azz thus far.

I'm from the Northeast and we got some really hot and humid days coming so I have decided to try to veg 18/6 that way I can have lights off during the hottest part of the day, not really what I wanted to do but really have no choice unless I went and bought a portable AC unit to cool the room down where the tent is in.

The tent has 2, 6 inch ports one on each side and 2 , 4 inch ports at the bottom back of tent...I currently have 1, 6 inch inline can fan 250 CFM connected on side of tent above the light as an exhaust (there is no ducting connected) so fan sucks air inside of tent out and blows back into the room. 3 passive air flaps on tent are open and there are 2, 6 inch clip fans inside of tent blowing up towards the light. The temps this morning inside of tent were 88F RH 56 while outside it was 78F at 11am. The room where tent is in was 82F

I still have 1, 6 inch can fan 250 CFM and about 25 ft. of flex ducting not hooked up so my best guess is I need to figure a way to exhaust out the window or at least out of the room where tent is. If I can just make inside of tent temp be the same temp as the room it''s in I think I'll be ok but thus far I haven't been able to do that.

I'll try to get some pics of this setup up soon, thanks for your time guys.

CO Finest really enjoy your YouTube page have lived on there for past 2 weeks :thanks:
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