First grow, BIG heat issue with my CFL's

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GreenGiant

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Hey all. I originally posted this thread on rollitup, but ive been reading alot on this forum preparing for my first small growing space. Ive found alot of good info here and i was hoping someone could maybe give me some advice.

About a year ago I got the brilliant idea of getting my own grow room. Unfortunately I didn't have a good space to use but a few months ago when I got my new apartment I thought I'd found the perfect spot for a stealthy grow.

During the last couple of weeks I have been doing research and benchmarking on different gear that I was gonna use. And I have been drilling, painting etc. just to make everything ready for my grow room. Just when i thought everything was finished and im awaiting my seeds in the mail, i decided to try to measure the humidity and temperature in the room.

Since I didn't have any good ventilation possibilities for the grow room, i'd decided to go with one 2700/6400K (one each) 200W LE light. The brand is Envirolites with built in ballast.

My grow room has the dimensions (height x width x depth):
80 x 65 x 40 (centimetres)
31.5" x 25.6" x 15.7" (inches)

So, I started my light and put the thermometer on the edge of the pots (as I thought there's where the plants will be).

The initial temperature was 73 degrees Fahrenheit (22.8 celsius), then it developed like this:
10 min: 81 degrees (27.2 celsius)
60 min: 98 degrees (36.5 celsius)

I continued measuring and after aprox 8 hours it seemed to stabilize on 109 degrees (43 celsius) (!!!!!!!!!!)

Here's a picture of my growing room:


I know its a small room (the light can be brought up higher), but i wanted a stealthy growing room. I measured I have aprox 40-50 cm for the plants (not including pots and lamp). I'm planning to grow lowryders / trying some LST-strategy/cutting down/bending the plants.

So, to my question.

Obviously I have a huge temperature problem and I was looking for some advice on how to fix it. One issue is that the grow space is in a cabinet space that is located next to the ceiling in the room. There is no way to create an outflow at the top of the room (except if i drilled a hole in the front panel, which would not be very stealthy). The only way new air can enter the room is from underneath, where there is another cabinet space. The openings to the room underneath is two x 1/4 inch "stripes" that located along the width of the room (the 25.6 inch-length).

I measured the temp in the cabinet beneath and noticed that the temp had not increased there, so obviously no heat is transferred between the two cabinet spaces (logical i guess since warm air moves upwards). Is there a smart way that i could get an inflow from underneath (through the small slots), or, rather blow out the warm air downwards? Or is this problem unsolvable without an exhaust in the top of the growing space? Can I use ice?

I was thinking about getting an ordinary oscillating fan to circulate the air in the room, and maybe i could cool off the plants just underneath the lamp. But i don think it will be sufficient. I also decided to remove the plastic sheets on the wall (the walls underneath is white anyway) as I figured the stone and tree walls inside the space maybe had better thermal conductivity . I tried this and also moved the thermometer so its not located just under the lamp. I thought this temp would maybe better represent the temperature if i had an oscillating fan blowing away the warm air just underneath the lamp. The temp in the bottom of the room is ~96 degrees so I guess I still need to go down.

Pic:



Do you have any advice for me on how to cool things down? Should I just forget growing in this space?
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Im feeling a little desolated now after all the work with the room, and now this... Any advice is appreciated.

gregi.jpg


gregi1.jpg
 
is there any space for you to drill a hole on the topside of the cabinet?
exhausting to the underside cabinet would work i think, but it'd be better to exhaust out the top and have a passive intake below. you could even use a small computer fan... just my thoughts
 
GreenGiant, Fresh air for your plants is every bit as important as the lights, nutrients, or medium you use. Without a constant supply of fresh air you will have alot of stretching in the plants and very poor growth. You really need to find a way to exhaust air from your grow room and bring in new fresh air for more than just the reason of high temps. Although doing so should solve your temp problem as well.

I hope your able to find a good solution for your needs :)

Warfish
 
Thanks for answering.

ishnish: There is one way that i could create an outflow in the top and that is to drill a hole to the left into another cabinet (these cabinets are all connected with each other and integrated with the wall, i live in a very old house). The only problem is that the wall between the cabinets are 1 inch thick and I had trouble just getting a power supply cord through... the idea of creating a hole with say.. a 3 inch diameter almost brings me to tears (im not very "handy"). I might consider trying to drill there to see how easy it is to get through, if that would work, would it be sufficient with a 12Vs computer fan? Another question: If i create an out blow in the top, will my passive "inblow stripes" (the ones i mentioned in my original post) start pushing in air from underneath? Im just a bit anxious to put effort into creating an outblow with a computer fan, and it ends up not being sufficient...

I tried having the door to the cabinet wide open and still doesnt go lower than 86 degrees... With that said it seem to me that these 200w CFLs emit a whole lot of heat after all :(

warfish: I've heard that before but I guess I've come to realise just HOW important it is. I wish I had made more thorough research before i started buying things.
 
Hey, GreenGiant, welcome! I'm just curious if you have a spot for a small grow tent? As a standalone unit, a grow tent is easier to ventilate and attach fan(s) to. I ask because as you've already heard, unless you get your space vented and supplied with fresh air, you're going to have lots of problems. What are you growing? :)
 
Hey ArtVandolay, thanks :)

I do have a spot for a small grow tent, its just that im trying to keep this project a secret. I dont want anyone to know about it (except you strangers on the internet :) ). People come and visit me every now and then, sometimes without notice... I guess that would be a problem with a grow tent standing in the middle of the living room lol! (i guess that means i dont have room for it, im living in a pretty small apartment.)

And for now im not growing anything lol... As i've come to realise, the plants would not exactly thrive in my "growing-sauna". :(
 
Want my advice. Be alittle bit of coin but... Get a grow tent, whatever size you want. Put the correct light in there at 5k lumens per sq ft. Put in a CO2 tank and regulator with controller preferably but you could do without. Put in a 4" fan with carbon filter. The more you spend on a fan in general, the quieter it will be. Hang the fan with bungee cords an wrap it with some type of insulation to quiet it even more. You can put a used tiny or bran new ac unit in there to keep it nice and cool. Cut back on a few things to cut into electricity costs.

PS, as far as ppl coming over, it's your place. If you want to grow in a small spot like that, you need to seclude yourself for a few months. If done right, you could produce enough to last for awhile. Just tear it all down and scrub everything down.
 
I'm a little confused here...what are the dimensions of your space? Dimensions are generally written length, width, height--your height isn't 15.7" is it? In the first picture, it doesn't look like you are going to have enough height...

Without knowing the square ft of your space, it is impossible to tell you how much light you need, but I would recommend a small HPS in a cooltube (Fluoros are actually hotter, lumen for lumen than a HPS). You also need to exchange the air in your space all the time the lights are on.
 
GreenGiant, you ust need to start and get handy with things, drilling a hole in a 1"thick wall is a piece of cake dude, i've done so many BIG holes the biggest was like 3ftx1ft in 4" cement walls. if it's wood, just use a drill with a circular saw head it can cut through it in seconds, however if you vent into the cab next to it and it's closed then you're really not venting at all, you would need to make a hole that exits that cab and another hole for air to come in. i suggest you exhaust out of the house from a window or wall because you say people are visiting you and venting in would cause weed odrs in your home, fans also give a hum so people would question why is that cabinet humming? :D good luck
 
Hey all.

So thanks for all the advice!

The Hemp Goddess:

My grow room has the dimensions (height x width x depth):
80 x 65 x 40 (centimetres)
31.5" x 25.6" x 15.7" (inches)
Sorry I wrote them in the wrong order before :)

The hooks in the ceiling, lamp and reflector takes up ~6-7 inches in height.
If I use pots that are ~7 inches then I will have about 17.5-18.5 inches (in height) free space for the plants. I know this is not a lot but I want to repeat that im not trying to grow something big here. Im no I cant expect to get big yields from a short plant but im doing this as a fun project and to lurn more about growing (if I get something to smoke that would be cool too ofcourse ;) ). My first seeds (which i wont be able to plant if i cant get down the temp and get some ventilation) will be Dr Chronics Lowryder #1. On his page it says they dont grow taller than 10 inches. Since i have ~16 inches available i thought i might give it a try. Maybe I could find some other low growing plants later on or try bending them down.
Ive seen pictures of people growing stuff in computer chassis or even smaller areas than Im planning to, thats why I started the project. I know most people think the area is too small but after seeing other people grow in smaller spaces i felt confident that it could work.

And hmm... the squareft. Im not used to counting with inches and foot (I use centimeters) but I think the squareft would be:

2.13 x 1.31 x 2.62 = 7.3 square feet (this time i wrote the measurements in this order: length, width, height).

Heres a pic i drew of the dimensions (I noticed I couldnt post URLs until 15 posts have been made, sorry hope im not breaking any rules now):
hXXp://i47.tinypic.com/20tmoom.jpg

I just read that 200W Envirolites gives 65 lumens per watt, so 65* 200 = 13000 lumens gives me ~1800 lumens / square feet. I have no idea if this is any good or bad. This is something I calcluated now, i had not looked into that before. I probably should have.

ArtVandolay: Cool setup :) It looks stealthy.

nouvellechef: Thanks for your advice, I will def. take that into consideration for future tries. But for now Im gonna see what I can make out of this.

zem: This growing space is a kitchen cabinet, its right in my kitchen. The reason why I thought it would be good is because its located pretty high up. Im much taller than e.g. my parents so they cant reach the knob :p (they visit me like once a week). I have connected all the power in the cabin to a switch so I could just press it if the door bell rings. Actually I could grow in there with the door open and then just shut of the power and close the cabin door. But then I think i need to wait till its gets summer because its way too dark this time a year and I guess the lights could make neighbours curious.

I was also considering drilling that hole, but as you say I would not be venting at all unless I kept the other cabinet open. Im thinking that its better to grow with an open door then since the fan would probably create a stroboscope-like light which would look really weird to have on 24/7 (if any neighbours would get interested).
 
Hey brother see a few problems. Need ventilation and a couple of fans. That will cease your heat problems. My main concern is your space. Mj plant's will double and even triple in size during flowering depending on what strain ya get. With your demansions ya don't have much room! Good ventillation will take care of the majority of your heat issues but your space i feel is to small. Maybe some auto's? Gl and keep us posted.
 
Hey Again

Ive been working some with my room and I decided to drill a hole in the top and added a computer fan. Now temp stays on 88 F which will have to do. I also managed to attach the lamp directly to the ceiling which gave me another 4 inches to grow on. I got my seeds today so I thought I will give them a go (try to start germinating them) today or tomorrow. I visited a local florist's shop to buy some distilled water. I had some pics but seems that I have to make 15 posts before I can show them :)

the chef: My first strain will be lowrider #1

Thanks anyway for all the advice everyone.
 
hey there GG :) good thing you drilled a hole in ceiling but you would need another hole for passive intake there. 88 is still high and it is probably much higher than the temp in room your intaking air from which also means plants are not getting enough fresh air hence your buds wouldnt grow good. your temp should be no more than 4 degrees higher than the temp of outside temps. finally you should make the light movable so you could raise it as plants grow since if its too far away at the start the plants will stretch out and grow poorly. light intensity decreases very much with distance, plants should be as close as possible to the light without burning them. for instance i keep my 400W hps like 10-12" away from plants. are you sure your resizing your pics? maybe thats why you cant post, well if you need 15 posts just post them here then post us pics :D hope this helps, cheers
 
Hey Zem, Thanks for replying

You're right that there's a big difference in temp between the room outside and the grow room. I do have a passive intake, its in the bottom plate where the plants stand on. The intake is 2 "stripes" of holes that are ~1/2 inch times 2 ft. So i think it "should" be sufficient.

I believe, that the reason that the temp still stays so high is that I got a too big lamp in the first place. I wasnt really aware of the dimensions of a 200w LE lamp - its huge. Of course I could probable decrease the temp further by increasing the ventilation, but as it seem now its not worth it (dont know how I would solve it without decreasing the stealth/ ruining my cabinette). I'd like to try the seeds that I got with the current setup I have. If the results are unsatisfactory, I will try to improve my space later on :) Im in no hurry here (and to be honest im a little tired of drilling and hammering right now ;) ).

I know 88 is not ideal but im hoping it might work. I measured the temp just below the lamp since I know thats where my plants will be (since I have little space to work with).


As you say, I guess it would be good to be able to move the light. I had easy rolls attached at first but they took to much of the space above the reflector. I figured i'd fix the reflector closer to the ceiling and then instead i could stack the plants with things to get the desired distance to the lamps.

Yes I resized my pics :) the 15-post thing seem to be policy stuff.
 
you do need a bigger fan :) seedling would cook at these temps, i uderstand your tired from hammering :rofl: i had to hammer through a cement wall just today, it always seems to be the hardest part but once you do it you see it's actually the easiest thing, it took me like 5 mins to open 8" hole in a 4" cement wall :D im only tryin to help you so not to fail, get a bigger fan, the computer fan is made to cool a PC not a 200watt cfl, thats all you need to do for now but i cant see you succeeding without venting this cab :) cheers
 
Yup, personally (no offence)I think your cabnet is not a good place for a growing environment, its way to small buddy... And they're right, constant air flow is very essential for growing. not to mention, 89 degrees is way to high.. I could be mistaken, but you want around 70-75 degrees. You can try but I dont think your plant is going to even survive if you cant get the temp down. If I were you id find a better spot or not grow at all... I suggest buying a grow box out of high times that is desguiesed(cant spell, de-skys-ed) as a file cabnet so that who ever comes over wont think anything of it, and therefore could just put it in your room. Hope this helps buddy and good luck.
 
GreenGiant said:
I believe, that the reason that the temp still stays so high is that I got a too big lamp in the first place.

Actually, you are really underlit for your space--1800 lumens per sq ft is not nearly enough to grow anything--you need almost 3 times that much light to flower. You are going to have to get more ventilation and more light in there if you hope to get anything out of this.
 
The Hemp Goddess said:
Actually, you are really underlit for your space--1800 lumens per sq ft is not nearly enough to grow anything--you need almost 3 times that much light to flower. You are going to have to get more ventilation and more light in there if you hope to get anything out of this.

I agree 100% , but i got question ur bulbs are 200w and u get 1800 lumens per sqf ??????? what is a totall ur bulbs puts out , becouse that is one bigxss bulb. and u should always have fan ur box room what ever it is heat issue or not is good for ur plants make the stronger (branches)

PLANT + FAN = STRONG PLANT = GOOD PRODUCT :)
 

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