Negative/Positive Air Vent Pressure???

[faithless]

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Trouble is I already own most of the lighting, almost 800w, currently.
That may be enough anyway, and if it's not, it's dead easy for me to upgrade if I want to. Just get another 250HPS or some fluors.
I'd love to get a cool tube otherwise. Can't be bothered with the hassle of selling it all either, in case someone suggests that. :rasta:
I wonder what a fan behind the lamps at bulb level and a stronger exhaust at the other end, also at bulb level, that leads out would do?

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[masterjointsmith]

yo ive got an idea..... details to come

[masterjointsmith]

details ... consider lay all your shit out in a line long way figure out what size piece of vent (probably square in your case) you can fit your shit in ontop of a piece of tempered glass that will hold the heft of all your lights and give ya a 2-4" gap all the way around your equipment .... lay your equipment on top of the piece of duct and trace around its "footprint" on to the duct with a sharpie put all your lights back on the piece of glass cut your holes slide the glass in the vent put a reducer on one end to 8" get a nice 8" fan to put on it and some flex conduit and pump the heat else where just my high thoughts

[masterjointsmith]

another thought i wouldnt cut a hole out of vent larger then 1/3 of the vent for structural reasons but maybe vents thicker where you come from poor paint brush jpg tocome

[masterjointsmith]

like this ya didnt give the any of your dimensions for the lights or the cabnet there goin in so maybe this is very poorly proprotioned/scaled but thats the idea and just exaust it somewhere out side

[masterjointsmith]

another afterthought i dont know what that shit will wiegh put togeather but maybe reinforce it with some earthquake strap bands (like a barrel but maybe a couple more bands then you got lights in it) then hang it from the bands that way it supported from the bottom

[GaGrown]

If you have a 265 or larger fan,Whatever size your exhaust opening is.Then that should be the size of the intake.It will be a bit of negative pressure. But moderate. It's the same principle as your central heating and air system in your home.You can't have more cfm's than you are pulling on the return. If you were to cut a 6 inch intake and a 4 inch exhaust,you would cool the room and exchange the air at an even rate.A 6 inch hole is 100 cfm.Distribute the cfm accordingly.Like part of it hook to the light.A 4 inch hole is 50 cfm.

Ga Grown!

[BOYZNUS]

Since smell isn't an issue for me, I have positive air pressure in my room.

It keeps the bugs and stuff under control.

And I use passive exhaust and hood exhausts.

Best of luck

[bongerstonerd00d]

Well, I read someplace on this site that you wanted your exhaust to be ~1.5 times the size of your intake. So I have a 4" Vortex bringin air in, and a 6" Vortex drawin stale air out thru carbon filter and it works great. Not sure if I have positive or negative airflow. I used a "Y" and I blow the hot air from 3 Sun Tubes out same line as my exhaust. Plants seem very happy wit the setup, too. Oh yeah, I go up to 8" duct hose just outside my grow area also. My room is 112" x 112" x 96" or roughly 650 cubic feet.

I am going to add a duct damper and CO2 next month. The WE grow sum trees


b0nger

P.S. Now this is a great discussion. Beats the shit out of reading "Where can I order seeds from"........<laffin>

[kent tha killer]

im running a 1000 hps in not even 4x6 and i battled that for awhile... i found what works for me is more exhaust than intake, not too much more or u will get a vaccuum affect and thats BAD, i find just run your exhaust when ur lightis on and have your intake kick in when your thermostat tells it to