Can't get below 93 deg..........

[fireman25]

.....temps ABOVE lights is 87.6F temps UNDER lights 93.0F

fireman25 Reviewed by fireman25 on 07-10-2008. Can't get below 93 deg.......... Heres my setup....... Closet - 48" H x 20"W x 20"D Single Waterfarm w/ 6" airstone 6 x 42 watt CFL Ducted 4" intake and exhaust mylar covered walls ( mylar wrapped around styrofoam panels) The room the closet is in is air conditioned down to 70 degrees I have my temp gauge located about 4" under the lights.......Is that the wrong place????? I can't get the temp in the box any lower than 93 degrees and thats with the room down to 70 and the fans constantly going. What am I doing Rating: 5

[signman2007]

Temp gauge should be located at the hieght of the tops of the ladies because this will measure your combined interior oscillating fan temp with your light temp at the plants canopy and thisis where it matters most. Right under your light it could be 100 and then the tops of your ladies be 75. Depending on how many CFM's you are moving through your box just keep an eye on humidity because mold will ruin your WHOLE crop!:smokin:

[hudson88]

Like signman says measure temps at the tops of the plants (or where they're going to be in your case, 4" is about right as you're using cfl's)

If i'm understanding you correctly you're using 2 fans, one for getting the heat out of the cab and one for getting fresh air into the cab? If thats the case, i'd use both fans for drawing the hot air out and make some more holes to be used as passive intake. This way you'll double the amount of air circulation and i'm willing to bet you'll solve your temp problems

e2a you might be able to get away with just adding a passive intake by adding another 4" hole at the bottom

[fireman25]

So with two 4" active exhaust and ONE 4" passive intake hole I should be good? Will I still need a fan in the box?

[hudson88]

two x 4" active exhaust but more passive intake, ideally it should be double the size of your exhaust, so 4 x 4" holes or 2 x 8" holes, but you can prob get away with a little less.

I edited the last post to say try just adding another 4" passive intake or removing your intake fan and making the hole 8" see how your temps are and add the fan back as an additional exhaust and more intake if needed.

e2a - as for a fan in the box, it does help to have one in to reduce any hotspots, reduce chances of mold , stengthen stems etc

[Hennessy1414]

dude when i get pics of my shit u will kno what 2 do.

all this other stuff is....well....there only so much a fan can do!

[hudson88]

dude when i get pics of my shit u will kno what 2 do.

all this other stuff is....well....there only so much a fan can do!

I'm sorry i disagree, if he's venting to and from a room with a temp of 70F there's no reason why the extra circulation he'll be given by rearranging his setup won't get his temps within an acceptable range.

[Hennessy1414]

I'm sorry i disagree, if he's venting to and from a room with a temp of 70F there's no reason why the extra circulation he'll be given by rearranging his setup won't get his temps within an acceptable range.

dude trust me i experimented with all of what your talking about.(granted i have an hps) but still if he wants any real wattage with cfl's hell get more=it getting hotter. just dude u will have to see. i love when growers challenge other growers(not to be mean it just drives me to make the perfect set!) It's truly the love of my life!
:rastasmoke:

[blink_inc]

Hennesy I can't wait to see your setup. I anxiously await....


What are the temps at the soil level?
What are the temps in the furthest corner from the lights?
What are the temps at the top of the canopy?

2 active exhaust is probably best with passive intake holes. Are your exhaust fans at the top of the box or the bottom?

[Weedhound]

The temps of the leaf surface needs to remain under 80 degrees for maximum growth. Anything over 80 on the leaf surface will slow photosynthesis (sp?) down greatly costing you in plant health and growth.

Buy yourself a small temp gun and see what your different surfaces are. Flat white reflects the lowest heat imo (80 degrees at surface vs 94 degreee heat reflecting off mylar) so losing the mylar will help.