xtensity

I know there's a ratio between how fast one fan sucks then the other. Intake should suck faster in faster or is it outake?

Or if at same speed is 1 bigger? I want to know if I should buy 2 different sized fans or just 2 of the same with a fan variable controller.

Stonewallace

I think the outtake should suck faster. If you have an exhaust fan air will automatically be coming in your intake without a fan as negative pressure right? If you blow air into the intake with no exhaust some will come back out but I don't think it's as much....I don't know the ratio. It just sounds kinda wild to me to have the same power in an intake as an outtake.

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xtensity

Whichever one is stronger, whether air is getting sucked out or in the opposite will happen at the other hole. Vacuum effect.

If more air is pulled in then air will get pushed out of the other hole quicker. If air is sucked out quicker then air will be pulled in through the other hole.

Anyone here know for sure how it should be set?

greeenhat

If I can summarize Jorge Cervantes' theory (look him up, read the bible), air should be exchanged every 5 min. Find cu. feet, H x W x D, divide by 5 and this would be your goal cfm. For a small space an active exhaust (with fan) and a passive intake (hole, no fan) should do the trick. Find a fan rated high enough to compensate for duct runs and pull air through the intake. This also creates negative pressure, helping to keep odors in check.

Also consider a carbon filter.

stoney-trees

Fuck George.

Did that crazy wanna be jamaican really say 5 minutes?

Id go by 1 minute in a warm place, 3 minutes in a cooler place.

Screw intake fans. More electric, and they are expensive. A hole is all thats needed. And only as much air as needed will come in...Provided your intake hole is big enough.

I mean no disrespect to anyone running an intake fan...But why the hell would you?

Floydism

I only see a need for an intake fan if the environment requires one. I'd say if your cab was confined, an intake fan would provide enough enough airflow so your exhaust wouldn't have to compensate for the loss. If you have a well constructed cab that's a little larger 4x4x8 something like this size, well passive intake is much more efficient. I use passive in my 4x4x7.5 tent with a heavy duty exhaust (stanley blower). Works flawlessly.

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Good luck on your crops everyone !

Journal-1:bagseed (male/failed)
Journal-2: Hashberry/Orangebud (current)

jwest810

i have the same tent, with two 1000 watt hps's and cant seem to keep my temps down lower than 88.. and i am blowing cold air in and sucking air out the top with a oscillating fan.. what the hell am i doing wrong?

Floydism

You aren't doing anything wrong, It maybe what you aren't doing... Take a pic of those 1000's watters I'd love to see how you have them cooled? Cool-tubes? Cooled hood/reflectors? What are you using as fans? In a room with AC?

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Good luck on your crops everyone !

Journal-1:bagseed (male/failed)
Journal-2: Hashberry/Orangebud (current)

Stonewallace

You suck the air out of 2000 watts of light with an oscillating fan. You should use a centrifugal fan.

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jwest810

no, i have the sun reflector hood shit with a nice 475 cfm fan on the end sucking cold air through from outside.. seriously
the only thing i dont have i guess is a fan sucking out.. i just have one fan blowing cold air in the other fan in line with the lights with the hoods and the whole setup, and thats all i have right now..
but i do have an extra squirrel fan lying around, can i hook that up top to make my sucking? and blow the cold air in from the top?