400w cab heat problem

I have a 2.5''X2''X5.5'' wardrobe cabinet. I had 2 65w cfl's in it shining on 2 small plants. The temperature was nice and fine averaging about 76-81.

Today I got a S&P TD-100X inline fan. its rated for 135cfm. I read everywhere that this is a great fan, very quiet and moves some air.

I mounted this fan at the top of the cab with a 4'' out hole on the back pushing air out. At the bottom of the cab I had 4 2'' holes ( actually pvc pipes to stop light leaks. I cranked it all up with my 400w hps 16'' from my 2 girls and temps hit 100 degrees in about 8mins. Once I saw that I imediately cooled of the cab took out the hps and turned back on my cfls.

Do you think the 10mins of extreme heat caused much stress??

and for the main question:
What am I doing wrong. Please give me some suggestions on how to cool this thing down. I will be very sad if I can't use my hps. I am also strapped on cash.

Please Respond, I need help immediately and am very sad

jbrain420 said:

I have a 2.5''X2''X5.5'' wardrobe cabinet. I had 2 65w cfl's in it shining on 2 small plants. The temperature was nice and fine averaging about 76-81.

Today I got a S&P TD-100X inline fan. its rated for 135cfm. I read everywhere that this is a great fan, very quiet and moves some air.

I mounted this fan at the top of the cab with a 4'' out hole on the back pushing air out. At the bottom of the cab I had 4 2'' holes ( actually pvc pipes to stop light leaks. I cranked it all up with my 400w hps 16'' from my 2 girls and temps hit 100 degrees in about 8mins. Once I saw that I imediately cooled of the cab took out the hps and turned back on my cfls.

Do you think the 10mins of extreme heat caused much stress??

and for the main question:
What am I doing wrong. Please give me some suggestions on how to cool this thing down. I will be very sad if I can't use my hps. I am also strapped on cash.

Please Respond, I need help immediately and am very sad

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**Also my room is at 72 degrees. **

I'm having the same problem. I've even tried venting my light with a 6" duct fan rated @ 265 cfm. My room is 2x4x8. If anyone has other suggestions I am all ears. I shut my light off @ 105 degrees, and that only took 20 minutes, how can I possibly leave it on for 12 hours??

420smoker said:

I'm having the same problem. I've even tried venting my light with a 6" duct fan rated @ 265 cfm. My room is 2x4x8. If anyone has other suggestions I am all ears. I shut my light off @ 105 degrees, and that only took 20 minutes, how can I possibly leave it on for 12 hours??

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I think the only solution is to buy or make a cooltube reflector. Im still reading...

suck the air out the top rather than blowing it out the bottom, but that still probably won't cool it down enough

cookin said:

suck the air out the top rather than blowing it out the bottom, but that still probably won't cool it down enough

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Thats what im doing. Im soo broke so I think im gonna have to try and make my own cooltube tomorrow vs buying one. I will go to walmart and get the lantern glass or something like that.

Do you think the cooltube could possibly cool down my cab 20 degrees? and get it down to 80 or so?

oh haha yeah .
how hot is it where you are getting the air from, i had one and it helped but not sure you'll manage 20 unless its pretty cold in the room.

actually you might be able to, can't remember how much it lowered my temps, def worth a go though if your building it

Your fan is really a nice one I love that brand but the cfm's are a bit low. I think you will get by though but you'll have to cooltube like you said.

You can also use candle chimneys from the big craft stores, they're less than $10.

The problem is you just got a light that's a bit big for that space. It'll be fine cooltubed though and it's better to have a little more than too little. One way to cooltube is to have it suck the air from the cab, another is to have it suck air from the room straight through and out. If you go the latter route a secondary smaller exhaust like even a couple computer fans on a wall wart might do the trick. Do not put any bends in your ducting. Straight as can be.

Also your intake's sound restrictive. Passive intakes are the way to go but if the tubes are too restricitve you might have to figure out some other way or just add more.

jbrain420 said:

I think the only solution is to buy or make a cooltube reflector. Im still reading...

Click to expand...

Yeah your right, I was just looking at other threads, and it does appear that the cool tube is our ticket to cooler temps. There are people using 600w w/ cool tubes in spaces as big or smaller than ours.

either a cooltube/vented hood or get a new intake source!

definately a cool tube type set up

I went crazy last night, flipped my cab over and drilled 6 more 1'' holes at the bottom of my cab. didn't help, so now I have about 14'' of intake. I read alot of diy cooltube threads, and im going to walmart today to see what I can come up with. Im gonna just try attaching a glass tube to me fan and hold the bulb inside the tube and see how hot it gets in 5-10mins. If it stays cool to the touch I will know it works, if not I don't waste any money.

I wish I went with a 200w hps instead now, but wanted the bigger yields. I figured Im better off giving them 100w sq/ft than 50. Whats the max heat mature plants can withstand during flowering.

If this doesn't work I guess im gonna have to sell my hps and buy a shitload of cfls. or possibly get a smaller hps.

You can make it work.

The ballast is outside the box right?

OregonMeds said:

You can make it work.

The ballast is outside the box right?

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Nope, but its at the very top, and it doesn't feel hot to the touch after its been running.

Do you think it will help to take it out of the box?

i had similar problem and i was reaching near 100 degrees in a 2.5 ft x 5 ft x 7 ft closet :s. Im an electrician so some things are easy to come by for me...i got a cheap bathfan...might be 70 cfm...and by cheap i mean cheaply built...it was free for me :O). I screwed the fan right above the plant and light to the ceiling, took a 4 inch duct from it and cut a hole in the ceiling and a hole at floor level in a side wall to act as a fresh air intake....fan comes on with lights sucks air from the room and blows it up into the deadspace above the ceiling...temps stay around 70-75 with a 400watt hps. Also as i waited too long to put into flowering so shes a bit taller than i was going for, so i hooked up my old 150watt hps flood light in there as well last night to help get light on lower branches. still only 70 degrees or so in there ) Am slowly running out of room overhead tho..lol...but hopefully another week of flowering and she will concentrate on the buds and come to a stop as far as height wise.....Also one more thing...not sure what kind of light you have. but if it has a remote ballast, then make sure to keep the ballast out of the grow area as it will put off heat as well....my 400 has one but the 150 does not...and im still so far so good with the temp....Hope this helps a bit

a forced intake is fine... what you need to do other than your intake is to make sure your cab / grow space is air tight... and get a bigger exaust fan 135 cfm's on a 400 watt hps is nothing... you could always go and buy flanges and come up with a cool tube design for your light and use that fan to cool off your light ( which will make a huge huge difference) and then something to exaust your room... y ou might "might" be lucky enough if you stick your current fan in your grow room about a foot away from your light (creating a cool tube ) sucking air from your grow bux through your light (cool tube) then out the box you might bring it down to a comfortable 80 some degrees... but I doubt it...

yes dude this is totally workable. Dont lose hope!

Can you get some ducting and run it to a part of the house that is colder or outside? This helps so much, even if its a couple degrees colder.

Build the cool tube! Just do it, dont question whether it would work, it will and youll thank yourself for spending the $$$.

In the meantime, get a normal fan and have it blowing on top of the plants in between the light and the tops. I have dealt with horrible heat problems while building my cabinet and I just harvested a huge hindu kush plant that was grown in the 90's for half its life.

If you can rig up a little co2 producer with sugar and activated yeast, DO IT. this will help in the meantime with the heat stress.

GOOD LUCK MATE

dusty26 said:

a forced intake is fine... what you need to do other than your intake is to make sure your cab / grow space is air tight... and get a bigger exaust fan 135 cfm's on a 400 watt hps is nothing... you could always go and buy flanges and come up with a cool tube design for your light and use that fan to cool off your light ( which will make a huge huge difference) and then something to exaust your room... y ou might "might" be lucky enough if you stick your current fan in your grow room about a foot away from your light (creating a cool tube ) sucking air from your grow bux through your light (cool tube) then out the box you might bring it down to a comfortable 80 some degrees... but I doubt it...

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i dont agree dude, as long as he can rig up the fan to the hood itself 60cfms would be enough to pump it out. I cool my entire close and my 400w hps with a 65 cmf active air squirrel fan.

I dont think its beneficial to him, especially if hes broke, to advise buying expensive fans when all he needs to do is rig up a cheap one correctly.

thrawn said:

i dont agree dude, as long as he can rig up the fan to the hood itself 60cfms would be enough to pump it out. I cool my entire close and my 400w hps with a 65 cmf active air squirrel fan.

I dont think its beneficial to him, especially if hes broke, to advise buying expensive fans when all he needs to do is rig up a cheap one correctly.

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and what temps do you average in there ?

dusty26 said:

and what temps do you average in there ?

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actually i average around 74-78 degrees with lights on. ill post a link to my venting setup if you want.

all i am saying is that if you design a ventilation system using trial and error, you can get every last ounce of power out of a vent fan.

then again, i think the intake placement is the most important aspect at keeping temps low.