Grow box, huge heat probs

S

Stun

Member
I have some big heat issues! Here's the set up: 3 x 2.5 x 5 box, 250w hps w/reflector, 75f ambient temps 50% rh ambient. Inside the box 103f 16% rh (no plants). I have a stanley blower moded from the rear sucking air out through 4" pvc and pushing out through 6" ducting conected to 4" ducting about 5 feet down the line, then a small peice of carbon filter conected to that (doesn't restrict much air flow), then 5 more feet until it's outside. Even if I have the diy carbon fiter inside the box off or on the temps are above 100f, even 3' away from the light. there is 5, 2" passive intake holes at the bottom and a small fan blowing up at the light. HELP!

How much does the temp drop when using a cool tube? How in the hell is it so hot in there?

Any help and/or ideas would be appreciated. I'm confused, expecially when I read posts about people's lights not being very hot.
 
XxNinjaxX

XxNinjaxX

Well-Known Member
Doesnt sound like ur fan can push the hot air all the way out.. What i mean is that ur outake is quite literally too long, and ur fan is struglling to push the air that far.. Because u are just pulling in air passively, it isnt forcing the old hot air out allowing for new fresh air.. Either shorten the outtake, get an intake fan or get a stronger fan for exhaust.
Hope This Helps - XxNinjaxX :joint:
 
B

B Irie

Member
Stun said:
I have some big heat issues! Here's the set up: 3 x 2.5 x 5 box, 250w hps w/reflector, 75f ambient temps 50% rh ambient. Inside the box 103f 16% rh (no plants). I have a stanley blower moded from the rear sucking air out through 4" pvc and pushing out through 6" ducting conected to 4" ducting about 5 feet down the line, then a small peice of carbon filter conected to that (doesn't restrict much air flow), then 5 more feet until it's outside. Even if I have the diy carbon fiter inside the box off or on the temps are above 100f, even 3' away from the light. there is 5, 2" passive intake holes at the bottom and a small fan blowing up at the light. HELP!

How much does the temp drop when using a cool tube? How in the hell is it so hot in there?

Any help and/or ideas would be appreciated. I'm confused, expecially when I read posts about people's lights not being very hot.
Click to expand...
I'd say the first thing you need to do is look into getting better and more efficient exhaust going. The whole 4" into 6" back to 4" ducting is a bad idea. Get a quality inline fan, and use the corresponding duct size throughout that system. Is the exhaust drawing from the top of the room? That's where the hottest air is to be exhausted. Get some air circulation going inside the box so that the cool intake mixes with the warm air of the room and doesn't just head straight for the exhaust. No body's lights are cool, I mean shit, were talking about like 1000 watts here. It's all about creating an environment where the hot lights don't heat up the room. Keep reading, there's a lot on this site that will help.
Cheers
 
W

watdafusmoking

Active Member
Hey brah I think your mane problem is that your trying to push the air instead of pulling it.If you cant move the Blower You might try a Inline Duct "Booster" Fan.They are not the same as a Inline Fan,lot cheaper.The fan is round and will slip right into the ducting you already have set up.Their really quit too I put one in my A/C vent in the living room.A 6" Booster Fan should make a big difference in temp.U will need a D/C plug.And imho you should move the scrubber to the intake side of the blower. Hope this helps brah.

Hey can you post picks of how you converted that Stanley Blower.those fuckers got some power.
 
S

Stun

Member
Shortening the outtake is an option to try.

The exhaust is pulling from the top rear of the box.

I'm not pushing the air out, the fan is connected to the back and pulling air out then pushing out the duct work.

I have a small fan at the bottom near the intake holes, I thought that would be enough to get some fresh cool air inside.

The blower was converted with a 5" to 4" reducer on the sucking part of the fan connected directly to the rear of the cab.
The only reason I didn't want to shorten the exhaust is because it sounds like an airplane taking off outside when the duct makes a straight shot to the vent going outside. I guess it's gonna take some fiddling around, but I don't have many options as space is a little limited and I only have 1 place to exhaust from.
Anyone know how many degrees a cooltube would bring the cab down, roughly?
 
Trunk5

Trunk5

Well-Known Member
simple simple solution, i use the stanley blower fan to exhaust my room and its great. look up my grow cab build, the space was 2x3x4 once i found that using that blower to exhaust the room thru my light hood worked best. it kept the space at an evan 84 with a 400watter. if i were you id buy that cool tube or pick up the sun leaves euro 6 inch cooled hood nice and small and works great with these stanley blowers. any questions hit me up or just browse my grow cab build and hell evan my new tent i use the same exhaust set up.
 
S

Stun

Member
Trunk5 said:
simple simple solution, i use the stanley blower fan to exhaust my room and its great. look up my grow cab build, the space was 2x3x4 once i found that using that blower to exhaust the room thru my light hood worked best. it kept the space at an evan 84 with a 400watter. if i were you id buy that cool tube or pick up the sun leaves euro 6 inch cooled hood nice and small and works great with these stanley blowers. any questions hit me up or just browse my grow cab build and hell evan my new tent i use the same exhaust set up.
Click to expand...
Do you have a carbon filter hooked up in that set up? I really wanted to just use one fan for odor and heat exhaust.... doesn't look like i'll be able to do that though. I just didnt want to buy a second fan, I was hoping the stanley could do it all.
 
Trunk5

Trunk5

Well-Known Member
i used the dyi carbon filter useing the two pencil cups and it worked great for my last set up. this time tho ill need a real filter cuz im going to have more going this time around.
 
S

Stun

Member
I have the 2 pencil cup set up as well. I can barely feel air sucking through it but I know it's working as the rh is so low with no plants in there.... I decided I will have to build a cool tube. Now the tricky part will be taking apart the light I have now to fit it well. The part the light is connected to is rather big and it doesn't seem to come off. Does anyone think sucking the heat off the light with no passive air flowing through the tube would work? If not my noob ass has no idea on how to rig it up with this stanely and carbon filter. I've looked at many diy cool tubes and none of them had the large base I do connected to their lights. Frustration is setting in...
 
Trunk5

Trunk5

Well-Known Member
your best bet is buying the euro hood from sunleaves, or a cool tube. have the blower hooked up to one side of the hood/tube exhausting air out of the room thru the light. put the carbon filter on the other end and youll be all good.
 
Green Cross

Green Cross

Well-Known Member
Doesn't your C02 filter absorb a lot of sound?

I'd blow the hot air out the top and directly into the scrubber. I know it's more efficient to pull off a scrubber, but if it's sound your worried about that should muffle it.
 
S

Stun

Member
Stun said:
Even if I have the diy carbon fiter inside the box off or on the temps are above 100f.
Click to expand...
Gonna need the cool tube, this bulb is HOT.

Edit: I see what you're getting at, nothing to do with the filter, just shortening the exhaust. I did switch it to the pushing side of the fan and noticed a little less restriction, I think i'll keep it that way. I don't want to exhaust the heat back into "this" room though.... it's not your typical box in a closet type of deal.
 
J

justfkngrowit

Active Member
You need air flow. You need intake and exhaust. As a general rule of thumb, you want to replace the air in your box about 3 times a minute at minimum. You cant just have an exhaust, especially in an air-tight room. You could leave the door open to your box if possible. That will make the temps go down a good bit.

Honestly, if you could, you need a bigger box.
 
S

Stun

Member
I have air flow. There's 5 2" holes at the bottom and a stanley sucking out from the top. The box isn't even air tight, I have the door cracked open as well. Like ninja said, I think I need to shorten the exhaust ducting for starters. I'm trying to figure out what will be my best bet for lowering the temps 20 degrees in there and i'm guessing the cool tube is going to be my best (and cheapest) bet. But I will try just shortening the exhaust 1st.

A box bigger than 3x2.5x5 for a 250w hps? I don't think thats a good idea, ventilation is the problem I have.
 
S

Stun

Member
Problem solved somewhat without building a cool tube (which I think i'll do anyways). Used some 4" ducting hooked to the exhaust and used a clamp to hook it to the reflector a couple inches away from the light, stuck a screw in the side of the box the height of the light on the opposite side of the ducting, hung a 4" fan on the screw blowing at the light / ducting. Shortened the exhaust to about 4' with the filter at the end of it... Brought the temp down from 103f to 85f. Good enough, but with a cool tube and/or more passive intake holes I think I can get it down to about 75f. I put my hand on the intake holes and man, that blower can suck some air! Thanks for all the help and ideas guys. Sometimes the simplest solution is the last thought in ones' mind... The Rollitup community is the shiz!

~Peace
 
greenfirekilla420

greenfirekilla420

Well-Known Member
Ya man in the future for bigger projects get you an intake fan as well. And wow ya you were in the same boat I was just my tent is prefabbed. I'm not using an intake, but both my fans as exhaust fans. I also have way more passive intake ports than "you to make up for it. I got three 5" socks at the bottom and then 3 4"x12" rectangular ports I can open and close. Next grow I will be getting another fan for an intake fan so I don't have to fool with opening and closing the passive intakes everytime the light shuts off or turns on.

:leaf::peace::leaf:
 
S

Stun

Member
Yeh, the bigger projects won't be happening. The room I have, the interest I don't. Just want to do enough to keep myself satisfied. This grow is in a dark space constantly, so light leaks on the box are of no concern minus odor control. The only reason I decided to build a cab was to control odor 100%.
 
greenfirekilla420

greenfirekilla420

Well-Known Member
Ya true but grow cabs don't keep it smell proof. You have to have enough carbon filtration to clean your grow space. Those small diy carbon filters will get most of it but there will still be some smell. I used the diy filters on my last grow box. I could still smell it when I walked in my bedroom but the whole house didn't reak which is what I cared about. Anyways

:leaf::peace::leaf:
 
S

Stun

Member
Spent $3 to build a cooltube! Using my original reflector with bulb attached, I hooked a large hurricane tube of glass ($3) by clamping it onto the reflector surrounding the bulb with a small clamp I had. Then hooked the exhaust duct into the glass with nothing, it slipped right in there perfectly. The exhaust is running through the cool tube so a 2nd fan wasn't needed. Works like a charm!
 
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