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Need help reducing grow room temp.

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WickedRites

New Member
I've recently built my first grow room and am having probs getting the temp below 90 degrees. The dimensions are L14xW4.5xH6.5. That puts me at about 410 cubic feet. I have a 170 Cfm exhaust fan mounted externally to remove air from the room which should probably t me exchanging the air every 2.4 minutes. I am using passive exhaust system with a 16inx16in intake at floor level on the opposite end of my room. My temp is remaining at 90 degrees and I can't get it any lower. It was at 99 degrees before I installed two oscillating fans to help circulate cool air from the other half of my room (flowering half divided by a Mylar curtain). I've already sank a ton of money into this(at least a ton for me) and can not afford to add an ac unit and a co2 regulator. Can anyone give me any tips to help me lower the temp in my room using a passive system or a cheap alternative. Also I'm using 1k lps bulbs. I couldn't afford enclosed hoods so they are open to the room. Ballasts are not inside of the room. my seeds are I. Germination atm and seem to be doing okay. I have about two more days to get my temp under control. Thanks for any help offered.

Edit: After reading the responses it looks like there is no cheap fix. At this point I'm wondering... Will I be better off if I just go ahead and buy cooled hoods rather than more fan? I'm just looking at cost and thinking it's the same either way. Whatever I do the next move has to be a fix. I don't have hundreds more to sink in to it or I wouldn't even be in this situation. I basically need to get through grow one then I can reinvest and go all out t on grow two.
 
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WickedRites

New Member
Diabolical666 said:
You are going to need more powerful exh and int fans since you are not running any cool tubes
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I don't currently have intake fans, is a passive system not pheasable in my situation? If not what fans do you suggest. Lowes has 250 Cfm Inline fans available for $30. That's the cheapest I've found readily available arm. Or could I use cheap window fans for my intake and would the cut to fit carbon filters work on an additional exhaust fan until I can afford another tall boy carbon filter?
 
bravedave

bravedave

Well-Known Member
^^^^is right. I have half your cu ft, also have an open air light (600w) and a 435 cfm Hurricane centrifugal..
 
W

WickedRites

New Member
bravedave said:
What is the temp of the air outside of the room...the air passively being brought in?
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Between sixty and seventy degrees. I built the room inside of the crawl space section of my basement so it's nice and cool under there. Flowering side is at about 79 with the lights off and I plan to run lights on opposite schedules.
 
hotrodharley

hotrodharley

Well-Known Member
WickedRites said:
Between sixty and seventy degrees. I built the room inside of the crawl space section of my basement so it's nice and cool under there. Flowering side is at about 79 with the lights off and I plan to run lights on opposite schedules.
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It might feel cool to you but it sounds as if it lacks circulation in the crawlspace itself. Sealing attics or crawlspaces entirely is not wise. Do you have crawl space vents above ground level to the outside?
 
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WickedRites

New Member
hotrodharley said:
It might feel cool to you but it sounds as if it lacks circulation in the crawlspace itself. Sealing attics or crawlspaces entirely is not wise. Do you have crawl space vents above ground level to the outside?
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Yes there are several ports to the outside within the crawl space. I placed a thermometer in my crawl space to check the temp before responding before.
 
bravedave

bravedave

Well-Known Member
WickedRites said:
Between sixty and seventy degrees. I built the room inside of the crawl space section of my basement so it's nice and cool under there. Flowering side is at about 79 with the lights off and I plan to run lights on opposite schedules.
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Then you really need to heed @Diabolical666 's advice. Personally think you can get by with the passive intake but you just need to pull that cool air in faster.
 
Flagg420

Flagg420

Well-Known Member
1000w's on a 170cfm?

Get yourself a 400-440cfm 6" in-line (dont go cheap, and dont get it at a local hydro store thats wasteful) add a speed adjuster for best sound/temp balance......

And stop reading big numbers on boxes at big box stores... lowes does NOT have a 250cfm in-line fan for $30.... they have BOOSTER fans, which will reach 250cfm in a closed system with a real fan in addition.... (like selling 5TB drives that are 4.5TB... all in the advertising, and the fine print)

If needed, get 2 fan speed controllers and use the 170cfm for your intake.... then adjust for proper air flow, while maintaining negative pressure... If u pull the fresh air from 'outside' make sure to use a bug screen. (this will give u plenty of fresh co2 tho)

My cool air comes from under my house on a 4" inline fane, I run 2 6" fans for lights (one on veg lights, one on flower lights)
 
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WickedRites

New Member
Flagg420 said:
And if your 170cfm fan is also a booster fan.... be happy there hasnt been a fire, lol
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I'm not using a booster fan. I bought a 4 inch from htg supply on the web and thought it would be enough. $15 would have gotten worse the 6 inch but I didn't think I needed it. Lesson learned, hopefully I can get em to let me make an exchange lol.
 
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WickedRites

New Member
Flagg420 said:
1000w's on a 170cfm?

Get yourself a 400-440cfm 6" in-line (dont go cheap, and dont get it at a local hydro store thats wasteful) add a speed adjuster for best sound/temp balance......

And stop reading big numbers on boxes at big box stores... lowes does NOT have a 250cfm in-line fan for $30.... they have BOOSTER fans, which will reach 250cfm in a closed system with a real fan in addition.... (like selling 5TB drives that are 4.5TB... all in the advertising, and the fine print)

If needed, get 2 fan speed controllers and use the 170cfm for your intake.... then adjust for proper air flow, while maintaining negative pressure... If u pull the fresh air from 'outside' make sure to use a bug screen. (this will give u plenty of fresh co2 tho)

My cool air comes from under my house on a 4" inline fane, I run 2 6" fans for lights (one on veg lights, one on flower lights)
Click to expand...
Flagg420 said:
1000w's on a 170cfm?

Get yourself a 400-440cfm 6" in-line (dont go cheap, and dont get it at a local hydro store thats wasteful) add a speed adjuster for best sound/temp balance......

And stop reading big numbers on boxes at big box stores... lowes does NOT have a 250cfm in-line fan for $30.... they have BOOSTER fans, which will reach 250cfm in a closed system with a real fan in addition.... (like selling 5TB drives that are 4.5TB... all in the advertising, and the fine print)

If needed, get 2 fan speed controllers and use the 170cfm for your intake.... then adjust for proper air flow, while maintaining negative pressure... If u pull the fresh air from 'outside' make sure to use a bug screen. (this will give u plenty of fresh co2 tho)

My cool air comes from under my house on a 4" inline fane, I run 2 6" fans for lights (one on veg lights, one on flower lights)
Click to expand...
about he fan speed controller... How exactly does that work and how do I know when the settings are right? Is hat going to make my fan more productive than if it did not have the controller?
 
W

WickedRites

New Member
Flagg420 said:
And if your 170cfm fan is also a booster fan.... be happy there hasnt been a fire, lol
Click to expand...
Ok sorry to be a pain but now I'm wondering, can I use the filter I already have? It's a 4 in tall boy carbon filter, or would I have to buy a 6 inch as well. Also will it not be a problem if I'm using a 4 inch intake and six inch exhaust? Or could I just use both fans with filters and create a passive system? I know I'm asking a million question but I want to make sure I get it right this time cause the clock is ticking for me. If I don't get it right this time I'm going to have seedlings sitting in 90 degree temps and I don't think that will work out too well.
 
Flagg420

Flagg420

Well-Known Member
u can get an adapter but keep in mind, doing to reduces airflow...

If passive is enough for fresh air, and the 6" exhaust works.... run ur 4" on the 4" filter just as a scrubber, independent of exhaust...

The speed controller allowes you to not run it 100% unless you need to, you can turn it down to make it quieter and keep the temps low at same time, just gotta find the right spot on the dial...

The controller is NOT necessary, its just to dial back the fan if it is more than 'needed' (It wont be 'too much' long as theres passive intakes)

(I replaced mine recently with a neat toy I got on amazon, a thermostat controlled outlet, for kicking on ACs and heaters... when temps get above 74f my exhaust fans fire up, its rather nice...)

In the future, yes, lights and fans, go big and turn it down if you need to, better to have too much than not enough.... Dirt, nutes, grow media, pesticides... tons of places to save money n go the budget route, fans and lights, always go big.
 
Flagg420

Flagg420

Well-Known Member
(If you NEED the filter on the exhaust for stealthy reasons, I would indeed get a 6" filter for best results. I like the ipower one, budget style sure, but both ends can be removed to reverse it (doubles life) and replace the carbon when its spent... ....come to think of it... I like their vented hoods and bulbs too lol)
 
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WickedRites

New Member
SPLFreak808 said:
Pics of the setup please! Where is your thermometer? Under the light?
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I can't figure out how to send a pic from my iPhone and can't get my hands on my laptop rn cause of kids. As soon as I can I'll post pics. I have my filter placed as close to the center of the enclosure as I can. My thermometer is at canopy level about 2 feet away from where the light hangs. I've got several thermometers throughout the room and the temp seems to be even all around. You'll probably laugh at my setup when you see it. I have a curtain between veg and flowering rather than a zip wall cause I needed my other zipper to access the crawl space. I assume the curtain will suffice but I'm getting residule light from the other room. I'll cross that bridge when I get to it though. The temp is my biggest concern right now cause funds are running low.
 
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