4000W Flowering Room Design - Light Venting Question

Ok so i'm in the process of designing my flowering room. We're trying to make this as modular as possible to expand as we need to. I've got a warehouse about 3200sqft. It has no central AC but has 22' ceilings so since heat rises we should be in good shape...

So our modular tent city will consist of 10x10 tents made by Secret Jardin. We'll be using the i300's as they can be connected together. Eventually each flower room will be 10x20.

Running air cooled lights in series seems like the 2nd most innefficient way to do something. Especially when you consider there would be 8 in a 10x20 space. 4 running in each row. So the heat will just travel down the ducting and not do much by the time it gets to the 4th bulb.

Parallel setup seems a bit more complicated and more efficient as each light is receiving the same ambient air temperature. Now how to do this in a sealed room environment.

I'm thinking of running 12" ducting in the corners of the tent from front to back. This 12" ducting would be open on both sides for intake portion and sealed on one side for the exhaust portion. The open end of the exhaust will have a fan sucking the air out.

I dont think i want a seperate intake and exhaust connection to this 12" as that would be a ton of ducting to do but running only 2 lights in series should work. So that the air is traveling across both bulbs and out the same exhaust. If only i could draw it on here to explain better. I think i'll scan some design work and see if anybody has input on this one.

thoughts...ideas?

here's a quick sketch of my idea.


View attachment 1455846
The 12" ducting would be solid ducting not the flexible hoses. The pieces connecting to the hoods however those would be flex hose, fiberglass insulated as well.

Think we've modified this a bit more...instead of running intake ducting on one side and exhaust ducting on the other. each side will be equipt with an intake trunk of 8" and an exhaust trunk of 12". Each light will be ducted individually to the trunk lines. now we should remain cool!!

It looks like an ambitious project and in theory should be just what the DR ordered.

Hum, I don't think you got the fans right. I mean, don't you think the lights closer to the 12" would suck more air then the lights father away? I would think it would be better to have two smaller fans 1 per set of lights pushing fresh air across the lights to the 12" ducting then out. I dont think you would need that 12" fan at the end at that point.

run fan to y to paired hoods out dont use y at end causes too much air restriction

buddy uses this for a fan works awesome ill be doing the same once i jump up to 4k watt from 2k watt
http://www.harborfreight.com/8-inch-portable-ventilator-97762.html

the reason it is built larger is because we intend to add another 10x10 tent to the existing vent fans. the 12" duct runs will be 20' long and be sucking air from all 4 hood simultaneously. This will occur on both sides of the 10x20 environment. So in theory there is apx 285 cfm coming across each bulb of outdoor air. If i add a Y then i'd need to increase fan size or move to the vortex V series with about 2050cfm's in capability vs having 2 individual ones @ 1140cfm's a piece. i'm not certain if the fans closest to the exhaust duct will have a greater suction capability than the ones further away. in theory a properly designed system should have that problem. but i'm not HVAC technician so i'm here posting about it. lol. i just know that blowing hot air over a hot bulb no matter how fast you do it isn't going to get it much cooler. have been to several grows where they do it the same way and always are adding A/C units to combat the heat problem. so i figure, do it right...12" exhaust, 8" intake for each light individually, use saddle taps on the intake and exhaust ducts to allow me to have the lights wherever i need them and the shortest straightest run to either their source of fresh air or outlet of heated air. gonna make another drawing since i've added it up and figured the cost. is about as much as adding another A/C unit which is funny. but the electrical cost of an A/C vs an efficient vortex fan ins't much to argue about. none the less...any more thoughts?

There ya go, I didn't see you planed on having fans behind the lights.

Go water cooled perhaps?

i looked into water cooled. just don't see it making the cut year round. too much humidity build-up possible when the outside temperatures are in excess of 90. really some cool setups by hydro innovations though. it is possible in the next grow, but that would be a totally open environment much like a greenhouse. ohh that'd be a fun project to design and build out.

i've decided on the Max fan 12" running my exhaust vents. with 1708CFM they're sure to cool a run of 14 individually piped lights. hell they may even work for a total of 6 lights individually piped across a 30' run. going to use a mini-split 12K BTU in each 10x10 environment 20seer rating on that thing so we're working on making this as efficient as we can.