heat problem. need help asap

im currently running 4- 13w cfls (daylight), 2- 40w cfls (1 cool white, 1 soft white), and a 15w, 18" florescent tube.
Problem is, the temp. is up over 90 degrees. I've got 2 fans running right now, 1 going into a diy carbon filter, and one just circulating the air around the space (2 plastic storage boxes, 1 upside down ontop of other). I had another fan blowing air into the box, but that broke and i gotta pick up another 1. I didnt have my thermometer until after the fan broke, so im not sure of the temp. when all 3 fans are going. Do you think it would make that much difference? If not how can i keep the temperature lower???

unless you know the specifics of pressure and all that whatnot i think its easier just to have a passive intake. i tried putting fans on my intakes thinking it would help and it raised the temp 6 degrees. only suggestion i could give would be better exhaust or more intake

You defidently need better exhaust over intake

I agree, you need to have air flowwing through the cabinet

So make one of the them the intake, one for the plants, and an exhaust fan

PowerFlower420 said:

You defidently need better exhaust over intake

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not exactly. if his intake is to small his exhaust is not blowing out enough and intake is not sucking enough cool fresh air in. i made my intakes bigger and made a considerable cut in temps. your intakes should be 2-3 times the size of your exhaust. if their not try making them bigger and see what happens.

Intake fan needs to be as big or bigger than exhaust.

A cheap exhaust for this is a bath exhaust (50 cfm) from Home depot...use another one for the intake...less than $30 for both. Blow intake across bulbs and exhaust out other side.

I have tried passive intake on a 2x3x4 box with little success.

is a 50cfm bathroom exhaust even worth it you can get a 10$ computer fan thatll push 70-100. anyways i think you should just try the free and easier option of bigger intakes if their smaller then your exhaust.

skervy said:

is a 50cfm bathroom exhaust even worth it you can get a 10$ computer fan thatll push 70-100. anyways i think you should just try the free and easier option of bigger intakes if their smaller then your exhaust.

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Is this a rhetorical question?

dude your talking to an actual pothead i dont know what the hell rhetorical means lol

skervy said:

dude your talking to an actual pothead i dont know what the hell rhetorical means lol

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My bad...I just play one on the internet...and I stayed in a Holiday Inn express last night...so...

Hayduke: wtf are u talkin shit for man. Skervy asked a good fucken question, one that i'd actually like to know the answer to. Clearly, both me an skervy dont know how much of a difference these bathroom fans would make, and if it doesnt make too much difference id rather save 30 dollars. Now, im going to ask the exact same question, and before anyone asks if its rhetorical, no its not. I'm not trying to start shit here with anyone, but clearly not everyone knows all the stuff you know hayduke.

thanks to everyone else for the suggestions. First thing im going to do is install a fan identical to the exhaust one for intake. If that doesnt work, i'll either switch to the bathroom exhaust fans (if people say its worth it), or put a bigger more powerful fan in the box to replace the other one.

skervy said:

is a 50cfm bathroom exhaust even worth it you can get a 10$ computer fan thatll push 70-100. anyways i think you should just try the free and easier option of bigger intakes if their smaller then your exhaust.

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oldmancronic said:

Hayduke: wtf are u talkin shit for man. Skervy asked a good fucken question, one that i'd actually like to know the answer to. Clearly, both me an skervy dont know how much of a difference these bathroom fans would make, and if it doesnt make too much difference id rather save 30 dollars. Now, im going to ask the exact same question, and before anyone asks if its rhetorical, no its not. I'm not trying to start shit here with anyone, but clearly not everyone knows all the stuff you know hayduke.

thanks to everyone else for the suggestions. First thing im going to do is install a fan identical to the exhaust one for intake. If that doesnt work, i'll either switch to the bathroom exhaust fans (if people say its worth it), or put a bigger more powerful fan in the box to replace the other one.

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Dude, I was only trying to offer an easy solution that is available usually locally...I was not aware of a $10 muffin/axial/computer fan that pushes 70-100cfm's that comes with a cord...Therefore the $10 is of course a cheaper, more compact solution...Asking an obvious question that does not need an answer is a rhetorical question...it's context is often sarcastic...which is how I took it...I'm a big boy and as guilty of sarcasm as much as the next guy...so that is how I responded.

His response was kinda shooting down my throwing out an idea, along with my experience using passive ventilation with hot cfl's in a small space...rather than just offering a cheaper and better solution to help us all...which he did. Thanks skervy...A link or the name of the store where you can score one of these would be great.

So...No...there is no reason to pay more money for a weaker, bulkier fan.

And I was not trying to "talk shit"...

skervy said:

dude your talking to an actual pothead i dont know what the hell rhetorical means lol

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Hayduke said:

My bad...I just play one on the internet...and I stayed in a Holiday Inn express last night...so...

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LOL!!! that was so awesome i just spilt my beer all over my mouse! you guys are too much!

In response to the question, going the cheap way is better i think, especially if its drilling a few passive intake holes. I know first hand i have had some issues with heat and still do, the fan on my intake raised temps about 3-6 degrees. Heat is always an issue when doing a stealth or cab grow, one of the biggest problems to overcome. I want to try some plexi glass or something to separate the lights from the plants. Still debating what to do!

The reason people are seeing an increase in temps with the addition of intake fans, is that the intake fan is smaller than the exhaust...causing the exhaust to struggle and over heat a bit. It is possible that I have not experienced this because I added intake after I already had passive holes...because of this I did not need to match the cfm's of the exhaust (100cfm intake, 12 3/4" holes with 90 degree pvc elbows, 256cfm exhaust)

Sorry about the beer

For passive intake, is it as simple as just cutting holes? How many holes would be best?The thing is i've been trying to keep the box airtight (except intake and exhaust) so that the air in the space only gets out of the box by going throug the carbon filter, reducing dank. If i just cut holes for passive intake, would some air also leak out of the box through the same hole. I know that since air is blowing out of the exhaust, the air to replace it would be pulled in through the holes, im just not sure if it could get out at the same time.


As well, if i get 1 bathroom exhaust fan for intake , and keep the PC fan for exhaust would this be sufficient, or would the bathroom fans only be worth it if i get 2, 1 for intake and 1 for exhaust.

oldmancronic said:

For passive intake, is it as simple as just cutting holes? How many holes would be best?The thing is i've been trying to keep the box airtight (except intake and exhaust) so that the air in the space only gets out of the box by going throug the carbon filter, reducing dank. If i just cut holes for passive intake, would some air also leak out of the box through the same hole. I know that since air is blowing out of the exhaust, the air to replace it would be pulled in through the holes, im just not sure if it could get out at the same time.


As well, if i get 1 bathroom exhaust fan for intake , and keep the PC fan for exhaust would this be sufficient, or would the bathroom fans only be worth it if i get 2, 1 for intake and 1 for exhaust.

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I wonder how loud these bathroom fans are, mine is pretty loud, do they make ultra quiet ones?? mine is from 94! lol, i would think they have gotten quieter over time.

haha i know man the fan i got in my bathroom can be heard threw my whole house. but im sure they got quieter ones. I've also been told they have decent fans, slightly bigger than pc fans at stores like the source and radioshack, im not sure of this though.

Alright so what im thinkin i could do to solve my problem is this: I got a box fan from my basement, and basically cut everything out to make it smaller, and im left with the motor and fan blades. I also got something like a light dimmer for fan (idk what there called i think u'll know what i mean though) so that it doesnt blow the plants to mcuh. lol. I've also still got the pc fan moving air through the carbon filter. The other thing i think im going to do, since hot air rises, is cut 2 or 3 holes out of the top, and put small carbon filters so it doesnt dank as much.

What i need advice on is this: with the box fan, should i have that as my input fan, also circulating the air inside the box. Or should i just have the fan in the box circulating the air, and have holes near the fan for passive intake, and the fresh air would also be circulated around the cab. The other option would be doing this same thing but having an intake fan rather than passive intake.

I need to get this problem solved asap so i can begin this grow, cause im psyched to get my first grow started! So ya, which one of these possibilities do you think would be best??? or if u've got any suggestions u think would be better, i'll definately consider them. thanks alot guys

oldmancronic said:

For passive intake, is it as simple as just cutting holes? How many holes would be best?The thing is i've been trying to keep the box airtight (except intake and exhaust) so that the air in the space only gets out of the box by going throug the carbon filter, reducing dank. If i just cut holes for passive intake, would some air also leak out of the box through the same hole. I know that since air is blowing out of the exhaust, the air to replace it would be pulled in through the holes, im just not sure if it could get out at the same time.


As well, if i get 1 bathroom exhaust fan for intake , and keep the PC fan for exhaust would this be sufficient, or would the bathroom fans only be worth it if i get 2, 1 for intake and 1 for exhaust.

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You will not get air going out through passive intake, unless exhaust is off...and there is a breeze.

If you can source cheep computer fans...do not bother with the bath fans...I have just found that they cost more than 10 bucks. The ONLY reason I use bath fans is the price and my love for all thinks hardware store.

The intake of a bath fan could be ducted in, allowing the fan itself to be in a remote spot...like somewhere cold (careful for bugs!).

But again....if I remember right, you are growing in 2 rubbermaid bins...the PC fans are the cleanest instal for this application IMO.

MikeyPeenz said:

I wonder how loud these bathroom fans are, mine is pretty loud, do they make ultra quiet ones?? mine is from 94! lol, i would think they have gotten quieter over time.

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They make very quiet bath fans....if you have the coin!

The cheap ones are fairly loud....they are all rated by cfm's and decibels