hey so I have two 600watt HPS lights cooled by one 6" exhaust fan. I have a separate 4" intake fan pumping into the tent and drawing air from outside the room. Room is hovering about 84 degrees. Someone said to have one fan per light with separate ducting? I thought that was crazy. Here's my setup currently ... sucks air through carbon filter, through one light, through the second, then out the tent
I don't know the strength of your fans but they seem under sized for what you're trying to do. I use cheap inline fans and my 6" is significantly less effective than my 8". If I were in your shoes I'd bump up the exhaust fan to an 8" and move that 6" to an intake position. Otherwise, I don't see a problem with using one fan to pull air through that gauntlet of lights and filter. Edit: I think 3fylon has the better idea with just adding another 6" as a booster in your 2 light, 1 filter line-up. However I disagree with the idea that you will lose little to no power by removing the intake fan. Any air resistance causes loss of efficacy of a fan.
How big are your fans? If you are able to get rid of any turns in your system it helps considerably. You could put your carbon filter at the other end of the system and get another fan (booster fan would be best option there, I think) You do not need an intake fan. Any air that is sucked out of your tent by a fan will come through every nook and cranny it can find with little to no lost power by the fan. If you are venting air out of your tent into a room, it is going to pull that same air back into the tent without cooling it very much.
6" out should be about 8" in. Almost double surface area creates good negative pressure and air exchange Edit: that is for passive air intake.. not forcing air inside to the room
Also.. lnletshould be at lowest possible elevation, and filter/outlet combo at highest possible elevation
You should try to be bring air from outside the grow tent/room for your lights - otherwise you just pulling hot air through the carbon filter onto the light - air outside tent will be cooler which will reduce temperature. You can get Y or T vent connector for few $ or ideally separate fan if you have some $ to spare
I read that pulling the air from inside the tent was the best way to keep heat down as it would be sucking out the warm tent air and exhausting it out, with fresh cool air coming from the intake
6" carbon sucking air out of the tent. 8" inlet allowing air to be sucked passively in. Outlet high elevation. Inlet low elevation. I would imagine that would be fine.. keep a 6" or 8" desk fan blowing on the bulbs.. I would think that would work?
You do not need 1 fan per light but you need a strong enough fan to move enough air for the added lights. Here is my current set up. Carbon filter > 6 inch duct fan > 3 cool tubes ( 3 600w ) > 8 inch duct fan > outside I have 2 rooms and the 8 inch pulls from both sides. So my 8 inch is pulling from 6 600w lights, with an added 6 inch fan in each room. My complete system is 2 240cfm 6 inch fans 1 740cfm 8 inch fan 6 600w lights So far my temps inside the grow rooms hover around 80 while my lung room is at 70. But its also winter and temps outside have been cold. True test will be summer with outside temps hitting 100. If need be i can upgrade the 8 inch to a 10 inch
It looks like ur just recirculating a lot of warm air.. u can't pull air in from somewhere else.. or release the air somewhere else? .. it's basically a really big box that's recirculating the same air from the pic.
You can't pull air from the large house as well? Instead of inside the small room where all the heat is? What are the average temps of the small room at floor level?
Basically you need to find a way to draw cool air in down low, and push hot air out up top.. your outlet fan should be plenty big for the size of your room. You don't need an inlet fan, that just adds more heat. Just make sure you have an inlet hole 8" in diameter and allow the air to be brought in passively... as long as the air being brought in is low 70s or lower u should be good