Ventalation: fans fans fans fans...?

[Opie Yutts]

Here's the deal: I have this closet for my flowering section and everything was fine until i switched from 400W to 600W. I just can't seem to get the temp down where it needs to be. My crops keep coming out a little brown from the heat, and sometimes a couple plants even die. Today I bought another fan, 6" about 270 CFM.

My question is where do I place my inline fans in the run of cooling ducts? There seems to be a great difference of opinion as to wether you should push or pull air through a cool tube or sealed hood. If I remember right, I think it was Zandor who said you should always push the air over the lamp. However I have read many times that you should have your fan after the lamp so it is pulled over it. And where in the run should I put the fans? Right near the light? At the beginning of the run? At the end? Middle?

Arrrgh! At this point I am ready to tear appart my settup and do it over once again. I want to be darn sure that I get it right this time. Oh yeah, I don't know if it makes any difference, but I have a CO2 generator. My 4" run is about 18 or 20 feet total. I plan to use the fan that I bought today, and a 4" fan, about 175 CFM. I am pretty sure I have enough sucking/blowing power now. My intake is near the floor in a differnt room which stays about 81 degrees in the summer. The run before the lamp(which is in a sealed hood), is about 6 feet, and the rest is of course is after the lamp which exhausts to the outdoors. There are two 90 degree bends before the lamp and two after. Please don't tell me I need the entire run to be 6", because the area of the intake will not allow it.

My initial thought on this to put the 6" fan right before the light, and the 4" inch fan near the exhaust opening. Any thoughts on this would be greatly appreciated, especially by HVAC experts.

Opie Yutts Reviewed by Opie Yutts on 07-21-2007. Ventalation: fans fans fans fans...? Here's the deal: I have this closet for my flowering section and everything was fine until i switched from 400W to 600W. I just can't seem to get the temp down where it needs to be. My crops keep coming out a little brown from the heat, and sometimes a couple plants even die. Today I bought another fan, 6" about 270 CFM. My question is where do I place my inline fans in the run of cooling ducts? There seems to be a great difference of opinion as to wether you should push or pull air through Rating: 5

[Forwhat420]

how high is high temps?

[Forwhat420]

with CO temps can usually run a little higher

[Opie Yutts]

In the middle it sometimes reaches 92. I have my light almost 2 feet away, and I would like it if I didn't have to pull it back even further.

[Opie Yutts]

My co2 is not set up yet. I have the generator installed, but I can't decide yet how to control it.

[Forwhat420]

usually you would like to keep the exhaust lines as straight as possible i run 2 600's and pull the air across them using fresh air (from on opening of the grow tent to the other) i keep my fan at the end of the run 265 inline and exhaust out the top with a 465 cfm this keeps my whole hut at about 78-80

[Forwhat420]

u may need to invest in a small air conditioner with those 92 degree temps!! lol.

[Forwhat420]

6in ducting would be the way. i would place the run all the top of closet and to keep 90 degree angles out and just place a home made stand for the plants to set up on

[Opie Yutts]

i keep my fan at the end of the run 265 inline and exhaust out the top with a 465 cfm

Darn! does this mean I have to take back my fan and buy bigger ones? And I figured out how I can eliminate one bend.

I acutally thought about tearing apart my old room air conditioner, and somehow puttting it in the duct line. Then there would be no problem keeping that bulb cool. Has anyone ever heard of someone doing something like this?

[Opie Yutts]

6in ducting would be the way. i would place the run all the top of closet and to keep 90 degree angles out and just place a home made stand for the plants to set up on

I'm not quite pictureing this. How can I bring air in from a different room, and exaust it out the side of the house, while having no 90's?