Ventilation Question (room sucking hard)

[sh2ft2]

I just built a 7x7 for my flower room i have a 8in 750cfm fan. I got my fan on as im putting up my thermal barrier and it seems that it wants to suck up off the floor and walls. I currently have one intake that is a 4"x8" floor vent.

Im not sure if adding another intake will take care of the problem or not was wondering if i could get some help or be pointed in the right direction would be greatly appreciated. Thanks:mmm

 

[ttystikk]

Just as Newton told us that what goes up must come down, air that comes out of a tent or other enclosed space must be replaced. A little negative pressure is fine and for smell reduction purposes even desireable, but a lot is problematic, as it shows you're not getting enough air turnover... OR, you're trying to move too much air.

If the temps in your tent are under control, try slowing the fan down. This is most easily done with a fan speed controller, they're like $18.00 or so most places. This can also help raise your relative humidity, which is desireable as well, as long as you keep it below 75-80%.

 

[Budwiser0908]

I just built a 7x7 for my flower room i have a 8in 750cfm fan. I got my fan on as im putting up my thermal barrier and it seems that it wants to suck up off the floor and walls. I currently have one intake that is a 4"x8" floor vent.

Im not sure if adding another intake will take care of the problem or not was wondering if i could get some help or be pointed in the right direction would be greatly appreciated. Thanks:mmm

Had the same problem. For me the excess negative pressure to remove odor in my space was more important. So I simply stapled and taped down the floor and put a couple of heavy object to hold the floor down

 

[hiboy]

whats that fan for, is it a cooling fan of your hoods or is it for air exchange.
h

 

[sh2ft2]

:party0044:ttystickk - i do have a fan speed controller and i turned it down a little bit and almost off didnt make much of a difference but at the same time it could be too much..

Budwiser0908 - i like the staple idea might do that to the walls i got metal tape up for now and its working but i went and got a 12"x6" floor vent and add into the wall as well for second intake i bought a magnet cover for incase it took away my negative pressure.

So since i added the second intake hole the temps in the room dropped from 81 to 76. It looks like and smells like i still have negative pressure the airflow is alot better in the room and the thermal barrier isnt really pulling for the exhaust but do still see slight pull.
My humidty constant at 47%.

hiboy - that fan is connected my hood in the room and is used to pull heat out of the room as well air exchange my room, the second light will be put up soon. but the second intake was good i believe. i looked around and found that twice the area of your exhuast is what needed for your intake.

INTAKE SIZING

Getting the intakes right is the biggest challenge in setting up a growbox. The intake area needs to be at least equal to the exhaust area and up to 2x to reduce losses.

A = pi * (radius)^2 = (pi *diameter)^2/4

so 8" fan equeals Area 50.2sqin x 2=100.4sqin. there for a 10x10 hole would of done for my intake.... im currently at 4x8 + 12x6 = 104sqin

im getting excited:party0044: