[FreezerBoy]

Originally Posted by Hundred Gram Oz

Hey man I got a question, I'm building a cab 10Lx5Wx6H Foot, I'll have 3 600w hps in there. What foot per hour or m3 per hour extractor fan should I have in there to have good temp control? And what intake should I have

Much respect

HGOz

Dude, it was right there on page one

[conehead]

Hey Red greenry top class thread!. maybe a bit above me but I'm trying to make sense of it all. I have a 12'' centrifugal can fan type it is 180watts I think it does about 350 liters per second, for an exhaust ( with carbon filter attached). Intake I have a 40 watt centrifugal bringing in fresh air from outside. I also have a scrubber with a small 4" duct fan 20watts & a very small stirring fan in the grow. My grow room is 9ft x 9ft x 9ft tall. Lighting used 1000w to 1800w. Does this set up sound O.K for the size room or is it overkill, or should I use passive intakes instead of the 40 watt centrifugal, this is where I am a bit confused!. Thanks Red for a great thread.

I had a pretty stable growing plan until reading further into ventilation (read: this whole thread) and heat so much that I am no longer sure what to do.

My plan is to grow 10 x auto hindu kush plants (Lowlife, seeds in hand). They aren't supposed to get any taller than 16". These would go into my closet, which is a closed/unventilated space, under a 400W CMH light. I was thinking of having two circulation fans for the space, directed on the plants, one on either side of the plants. Then I would also have two small fans mounted on the hood, directed on the CMH to cool the light. The ballast would be remote and outside of the closet space.

Now, I'm assuming that such a setup would still produce too much heat with the closet doors closed (I'm talking a 2-3' deep 8' long 8' tall closet) since there is air circulation but not ventilation. However, I would not like the closet doors open all the time and I would prefer the closet doors to not have vents put in them (this would not be stealthy). Are my assumptions correct?

So then I thought that I could cut through the wall of the right side of the closet and put in an exhaust fan, since that exhaust fan would exit directly to the outside of the house. This leaves the problem of intake. Any suggestions?

Finally, I plan on also having a cabinet (approx 4' tall 4' wide 2' deep) for mothers/clones/non-AF plants, with 4-6 x 42W CFLs. I can handle the intake/exhaust situation for the cabinet, so this is really just random fyi.


To sum it all up, I'm asking what the best setup would be for growing the 10 or so 14"-16" plants with the available space, with regards to ventilation. I'm open to doing a larger cabinet or more cabinets, and changing from my CMH plans to doing just CFLs. Would multiple smaller cabinets like the one I mentioned in the above paragraph be a better idea? I'm not partial to the idea of weaker yields with CFLs, but if that is the best option, so be it.

[InRainbows727]

I was wondering if somebody could aid me?
My box is a SOG style about 2x3x3 and I'm using a 130 CFM carbon scrubber w/Axial fan (exhaust). I am going to be using darkroom vents to eliminate all light leaks--my question is should I rather get 2-3 120 mm computer fans rated at about 36 CFM (passive intakes?) or should I go with a single 112 CFM Axial fan(easy because it's a single plug and merely one intake to whittle out of my box)?

Thanks for this thread.

I've sorta put off hooking up my cool tubes and I think it is because I don't know what is best to do in air flow...

Looks like that will change...

Jack

[SativaDreams]

Now that we have discussed fans, GREAT THREAD by the way i've learned alot about ventilation reading through the first two pages, can we discuss good sources online we use to find and purchase them?

I'm looking at some getting some smaller axial fans for the drawer to keep it stealth.

Anyone have good website ideas i could look at for ordering?

[petemoss]

I like the 12 volt computer case fans. Newegg.com usually has a good selection at very good prices. Scythe is one of the best brands.

Used wall chargers can be obtained at Salvation Army stores. I bought about 6 of them of various voltages for 50 cents each for my guitar effects experiments. They could be used to power a dc fan. different voltages of dc will change the speed of a dc fan. Go to a second hand store for dirt cheap wall chargers.

[SpendThrift]

I'm sure this has been covered multiple times but I cant find anything about it. If I were to use a 8" to 6" ducting reducer does that have any significant effect on airflow or lower the cfm at all?

[eglider]

Reducing from 8" to 6" will increase air speed which will increase turbulence that translates to higher static pressure (resistance). By how much I cant help you with because thats above my paygrade. You'll need Red to nuts and bolts that one for volume, speed and all that smart guy stuff. My guess would be that unless your fan is a little booster home depot job you would probably be okay.