CFL heat

Tonymon1

Member
I just can not seem to get my heat issues under control and I'm only using 4 23 watt CFL's. Temps are 85-90 (granted the house been about 5 degrees hotter than normal the past few days as well)

Cabinet is 44"tallx36"widex16"deep
Intake (bottom right corner) is 2.5" PVC trap, today I upgraded from 1 60mm fan to 2 of them on a 1 to 2 split PVC.
Exhaust (top left) is 4" PVC with a 120mm fan.

I decided to try creating a "hood" for the lights out of a shoebox covered in mylar, today I connected duct tube (metal, bendy) from the exhaust to a hole in the top of the hood, However it doesn't seem to do much if anything. Between the second intake fan and duct work it dropped around 2 degrees.

All I can think to do at this point is add another exhaust fan (was going to do that today but the 4" PVC is expensive) to increase how much air the exhaust is able to pull.

Does anyone know of any brands of CFLs that run cooler? I currently have Bright Effects (6500k) and Great Value (Walmart brand, 2700k they run hotter than the 6500k)?

Also, I know the big CFLs get hot but any chance they run cooler than multiple smaller CFLs?

I'm clearly doing something wrong because I've seen so many other similar grows using many more lights with no mention of heat issues. I know I could probably live with this heat, seeing as when the house temp gets back to normal it will be 80-85 with the lights on, but I'm going to need at least a couple more lights for flowering.
 

Essex

Active Member
double up the 120mm fan, make 2 fans thick. this will push more air out without need for any more duct
 

Tonymon1

Member
double up the 120mm fan, make 2 fans thick. this will push more air out without need for any more duct
Interesting, I'll have to try that. Thanks. I figured that would reduce air flow. But in terms of air flow and aerodynamics I seem to not quite get it.

My plan for expanding the exhaust was to get the same elbow I have and get a "T" type piece so the duct goes into 1 and out of 2.

I should have another 120mm laying around somewhere so I'll be giving that double idea a shot.

I currently have 3 fans hooked to a 12v plug, anyone know how many you can do before you overload it?
 

Essex

Active Member
add the A (amps) on the fans up and look at the A on transformer (1000mA = 1A)
if the fans are less than transformer its cool
 

Touchet

New Member
I use a T5 250 watt Feliz, and a 150 watt T5 Feliz, both 6500k for veg tables. The temps at the ballast are around 85*f. I can put my hand (the back) on the bulb and hold it there. You can see both being used in my journal. One is between 4" and 6" (depending on plant size) away from the tops of the plants. The other is about two to three feet, again depending on the size of pants in there.

In regards to your ducting, the more bends and "T's" you add the more static pressure required to move the air. I tell everyone pretty much the same thing on this point. Don't skimp on the stink. Meaning buy a carbon filter or rig up a DIY filter but move some serious air, it solves all kinds of problems. cO2, smell, and heat being the biggest. These three things are crucial to a great harvest. Spend $50 on a blower, spend $75 on a filter, spend $20 on ducting and call it a wrap.I can stand with my face smashed into my outlet duct and not smell anything other than warm humid air coming out. Exactly what I want to come out.
 

Tonymon1

Member
I use a T5 250 watt Feliz, and a 150 watt T5 Feliz, both 6500k for veg tables. The temps at the ballast are around 85*f. I can put my hand (the back) on the bulb and hold it there. You can see both being used in my journal. One is between 4" and 6" (depending on plant size) away from the tops of the plants. The other is about two to three feet, again depending on the size of pants in there.

In regards to your ducting, the more bends and "T's" you add the more static pressure required to move the air. I tell everyone pretty much the same thing on this point. Don't skimp on the stink. Meaning buy a carbon filter or rig up a DIY filter but move some serious air, it solves all kinds of problems. cO2, smell, and heat being the biggest. These three things are crucial to a great harvest. Spend $50 on a blower, spend $75 on a filter, spend $20 on ducting and call it a wrap.I can stand with my face smashed into my outlet duct and not smell anything other than warm humid air coming out. Exactly what I want to come out.
I'm thinking about (when I have the cash) getting some 2' T5's for my side lighting which would cut down on the heat rather than piling on the CFLs.

The carbon filter is something I plan on doing (DIY) however that's going to rely on me getting the heat issues solved because the filter impedes air flow, I'm legal and it's only a 1 or 2 plant grow so while I would prefer the filter, it's not top priority at this point.
 

Tonymon1

Member
Doubled up the fan and sure enough it's pulling much more air. I just hooked it up so only time will tell if it fixes my problem.

I will have to come up with a better idea though, between the 4 axial fans and the desk fan this box is LOUD, it sounds like a vacuum cleaner is running.
 

Tonymon1

Member
Little update... I went back down to 2 fans. The newest fans I added on the intake and exhaust where twice as powerful as the original ones so I pulled the less powerful ones. It is still loud as hell but not as bad. The loudest thing is the intake not the fan itself but the sucking of the air in the tube. I have no idea how to fix this but hopefully there is a way.

The biggest problem with the heat seems to be room itself, as it stays hotter than the rest of the house, likely due to the electronics (TV, PC, ect.) in it. The box it self does seem to be cooler than before I previously estimated the box to be about 12 degrees hotter than the room, with my changes it seems to be about 7 degrees hotter. I doubt it's going to be realistically possible to improve that.

Hopefully when it's time to kick the central air on I'll be in better shape. If not I'll look into a window unit so I can keep the room at the temp I want without the whole house being cold.
 

Essex

Active Member
If you use all the fans on a veriable voltage DC transfomer ya can turn the volts down and noise will follow :-)
 
double up on the fans like the one guy said and if you have time put an ice cube tray in there... refilling it gets annoying but i manage to keep my box just under 80 with it and it helps humidity
 
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