Major Heat Problem... Suggestions?

I have two 1000W HPS lights sitting above two 4x4 trays all inside of a 5x9 grow tent... I have ventilation running through both hoods with a big squirrel fan pulling air through and up into my ceiling. I put two stationary oscillating fans on each side and have them set on medium speed. I have no plants in the setup yet cause I didn't know what my conditions would be like. Everything has been on for about an hour and I just checked the temp... 94 DEGREES! What can I do if anything to resolve this problem? Any suggestions will help.

Aztros said:

I have two 1000W HPS lights sitting above two 4x4 trays all inside of a 5x9 grow tent... I have ventilation running through both hoods with a big squirrel fan pulling air through and up into my ceiling. I put two stationary oscillating fans on each side and have them set on medium speed. I have no plants in the setup yet cause I didn't know what my conditions would be like. Everything has been on for about an hour and I just checked the temp... 94 DEGREES! What can I do if anything to resolve this problem? Any suggestions will help.

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that's a lot of light/heat in a small space. you could have two 600's in there and get good light. even a 400 meets the minimum reqirements for light over a 4x4 tray. but to work with what you have:

1. you mentioned one squirrel fan. are you running the two lights in series? what is the cfm of the fan?

2. you didn't mention any venting of the tent itself. does the tent have its own exhaust (in addition to the one for the light?).

3. do you happen to have a portable a/c hanging around somewhere?

desertrat said:

that's a lot of light/heat in a small space. you could have two 600's in there and get good light. even a 400 meets the minimum reqirements for light over a 4x4 tray. but to work with what you have:

1. you mentioned one squirrel fan. are you running the two lights in series? what is the cfm of the fan?

2. you didn't mention any venting of the tent itself. does the tent have its own exhaust (in addition to the one for the light?).

3. do you happen to have a portable a/c hanging around somewhere?

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Yea I would much have preferred to put two 600's in the tent instead of the 1000's, but what ya gonna do when they're donated to you? My squirrel fan is 630 cfm and pulls air through both hoods in one vent. I do carry ventilation through the tent as well. Maybe add an A/C unit to the room? That's just more $$$ I don't really have.

Aztros said:

Yea I would much have preferred to put two 600's in the tent instead of the 1000's, but what ya gonna do when they're donated to you? My squirrel fan is 630 cfm and pulls air through both hoods in one vent. I do carry ventilation through the tent as well. Maybe add an A/C unit to the room? That's just more $$$ I don't really have.

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you can a/c just the tent with a portable unit. just vent its heat out of the tent. check ebay and craigslist for deals

Ha that's actually what I was doing right now. I see these big ones for thousands of dollars then these little ones that you empty the water out of every now and then for a couple hundred. Are those little ones what you're talking about or is there a certain kind of unit I'm not finding?

the little ones are fine. you size them based on the btu's of heat they can handle. don't have a link but if you search " air conditioner calculator" on the net you should find a tool to get the proper sized unit. i have a 12,000 btu portable a/c cooling a 350 cubic ft room with a 600 running and outside temps at 90 degrees.

I added some reputation... You've helped me before and I really appreciate it. I'm gonna get all this figured out... If you or anyone else for that matter comes up with something else I could try don't hesitate to let me know. I'm going to try to find me an A/C unit otherwise.

I've had some temp problems as well (seems to be a new fad)
If you don't want to spend the cash for the a/c something that helped me out, and i take no credit for this idea is using frozen water bottles inside of the grow area. It dropped temps for me by four or five degrees. Something else i saw that seemed to work for others was this Diy Humidifer/chiller For Small Grows - Grasscity.com Forums
Hope this helps
BlueberryDreams

What if instead of using these mini computer fans (one blowing in fresh air on one side and one venting hot air on the other side) I used squirrel fans and ducted the hot air with a splitter out the ceiling with the venting from the lights? Would the squirrel fan suck enough air through the tent to cut back my temperatures by roughly 15 degrees? I'm struggling and ready to put a group of plants into flowering, but do not want them to be in 93 degree temperatures. I don't have the money for an A/C unit. Bill's are piling up and between being in grad school and working full time at my legitimate job, my life is pretty hectic. I need a way to get this thing going, but have to get the temps controlled somehow. You guys think using squirrel fans could work?

Aztros said:

What if instead of using these mini computer fans (one blowing in fresh air on one side and one venting hot air on the other side) I used squirrel fans and ducted the hot air with a splitter out the ceiling with the venting from the lights? Would the squirrel fan suck enough air through the tent to cut back my temperatures by roughly 15 degrees? I'm struggling and ready to put a group of plants into flowering, but do not want them to be in 93 degree temperatures. I don't have the money for an A/C unit. Bill's are piling up and between being in grad school and working full time at my legitimate job, my life is pretty hectic. I need a way to get this thing going, but have to get the temps controlled somehow. You guys think using squirrel fans could work?

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can you draw a diagram of your setup? i'm always concerned when i hear "splitter" because you have to be careful to balance air flows for the two sides.

turn off one of the lights bro, 1000W is still good to grow both 4x4 with. Once you got some extra ($129 at wal-mart) cash then you can get a small 10,000 btu AC unit.

I was rummaging through craigslist and just got back from picking up a 12,000 btu A/C that works perfectly for 100 bucks. The guy is moving out of state in a few days and needed it gone so I gladly took it off his hands... He even gave me his receipt from Home Depot so that I still had the warranty! I looked at the date on it and the thing is only 3 months old and he payed almost $600 for it. Yea I'm tight on money, but I couldn't pass it up especially with my time crunch. I think I'm going to put ducting on it to carry the cool air into my tents. Or, would it be better for me to just run it outside the room at a cool temperature? Man... I was soooo incredibly stressed and everything came together just like that. Things always have a way of working themselves out. Thank you guys very much for all your help definitely opened my eyes to a lot of things I now know and can pass on to others. Oh and desertrat... You my friend are a bad ass. I want to thank you personally for keeping up with my thread and making sure I knew that someone was always there actively trying to help. You're a good man and are in my eyes a huge asset to the RIU forums.

NoDrama said:

turn off one of the lights bro, 1000W is still good to grow both 4x4 with. .

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nodrama is always right.

Aztros said:

II think I'm going to put ducting on it to carry the cool air into my tents. Or, would it be better for me to just run it outside the room at a cool temperature?

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best way is to have ac in grow area and vent the exhaust. most portables come with some ducting to get the hot air out of the room you/re cooling.

Aztros said:

I want to thank you personally for keeping up with my thread and making sure I knew that someone was always there actively trying to help. You're a good man and are in my eyes a huge asset to the RIU forums.

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you're welcome. i'm sure you'll help out when you know more.

Hey Desertrat... So I'm still competing with heat, though it's not nearly as bad as it was. When I have my tent closed up, lights on, portable a/c running, my temperatures stay at a constant 86 degrees inside the tent.

I've jimmy rigged my A/C unit which blows out cold air from an approximately 1x2 ft vent. I put some ducting on one side of the vent with a little DIU magic to carry half of the cool air into the tent. So now the A/C is blowing half into the general room and the other half is ducted through my tent. This brought my temperatures down to 77 degrees which put a huge smile on my face. The problem with this is when my lights kick off, the A/C ducting is still inside the tent and I'm almost positive it's bringing my temperatures down way too much. The A/C is set to its lowest setting at 62 degrees and I can't just put the A/C on a timer cause it keeps the room cool for my other tent which is the same size, but has a 600W MH that is on 24/0.

Ideally I would think a squirrel fan for both tents could do the trick. That way I could just put the fan on a timmer when the lights shut off for my flowering tent. Question is, do I have both fans sucking air out of the tent and venting it into the attic? Would I even need to duct into the attic? Would that force air to come in from the other side or would I need another squirrel fan bringing air in too? How powerful of a fans should I get for this task? Do you personally feel as though this is a good idea, or do you by chance have any other suggestions for me now that I have my overall room temperature under control without having to purchase squirrel fans?

Hope I was able to paint a good enough picture for you to get what I'm trying to say... Take care man.

why don't you turn up the thermostat to 72 f ?

The portable a/c is set at 62 and I'm still battling heat...

Oh... I just thought about your response. Keep the a/c at 72 and run the ducting into the tent until I have money to buy the squirrel fans? That way at night my tent wouldn't get too cold and would still allow for my other tent to stay cool too?

If I'm getting 77 degrees inside the tent with 62 degree cold air ducted inside while the lights are on. What do you think my temperatures will look like inside the tent if I turn up the temp to 72?

By the way, I just checked out your grow journal... You're plants are absolutely beautiful. I hope mine turn out half as good.

Aztros said:

The portable a/c is set at 62 and I'm still battling heat...

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the ac doesn't work any more if its set at 62 or 72. it will just shut off if your temps go below 72 and be on full power if above 72. if you have good enough ventilation it should equalize the temps in the room and shut down when your first light is off.

Ha excellent good call... Thank you.

In regards to the squirrel fans when I am finally able to buy them and get rid of my web of ducting, do you recommend I get 2 sucking air in, 2 sucking air out, or 4 of them 2 pulling air in one side and 2 pulling air out the other side. Also what cfm should I aim for?

wouldn't even begin to try to answer that one without a diagram. hard to imagine good ventilation without ducting to carry the heat away.