Tent Cooling/Filter Questions

So I put together a DIY tent and need some help on how I should cool it and what fans I should buy. The demensions are 6'6"h x 7'6"l x 4'3"w. I am running 2 400w set ups in it with 4" coolable reflectors. I want a inline fan/blower thats strong enough to push enough air through both hoods. Any suggestions on what I should buy? Should I put an extra fan on the outlet side to draw more air? Is it smarter to have a carbon filter on the outside of the tent with a fan drawing air out into the filter OR is it better to have the filter inside of the tent? Will a 4" air inlet fan from Home Depot be enough air supply to the tent? Basically I need help on exactly how I should supply air, exhaust air, cool the hoods and deal with the smell before I go out and buy a bunch of shit when I should've bought something else. I've seen designs on how its done but I really don't know what fans and carbon filters would be adequate for my space. My mothers are almost ready for clones so I need to get all this done asap so please help a brotha out.

you have 210 sq. feet and you need to change the air every 2 minuets so you need a fan that will be rated at 100 cfpm just for the air in the tent. Always go a little bigger a 200 cfpm would be ideal. As to your cooled reflectors you need a 4 inch can fan or vortex, this will allow you to cool in the summer. When cooling lights always push/ blow the air through the system. If you put the fan at the end and suck the air if there is a leak smell will get out.

Hope it helps

I have a 4" pushing air through two large air cooled reflectors in temps from 95 to -35 and have no issues cooling.

Peace

Thanks Wood.

But really thats all the help I can get? You guys are slackin!

u DONT wanna push the air threw the hoods!!!!..u wanna suck the air threw the hoods!..i have a 4x4 hydro hut with 2 600w 6" cool hoods..i run 2 400 cfm can fans..one for the lights "sucking air threw,not pushing" and one for my carbon filter..works mint!..if ur fan has a leak "which it shouldnt if its new" just duct tape or duct seal around the seams on the fan, simple easy fix!

Ok, so one guy says push the air and the other says pull it. How big of carbon filter do I need? How big of a fan would I need to suck air through that carbon filter without burning up the motor?

www.htgsupply.com they have fan/filter combo kits.. w.e. u feel like spending man.. i would go with a 6inch fan at about 300-400 cfm for that size room..thats just me though..

2012junkie said:

Ok, so one guy says push the air and the other says pull it. How big of carbon filter do I need? How big of a fan would I need to suck air through that carbon filter without burning up the motor?

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Yeah the gnome is wrong. As stated by woodsmeneh, you want to push through your fans and pull through your filter. You want separate fans... no sense wasting fan power pulling your hood air through the filter. Push air from outside the grow though the hood back to outside (not into the room). then worse case scenario, your hood leaks into your grow a bit and you add some fresh air. If pulling through the hood any leaks will put contaminated air outside your room without going through the filter first, and the heat that comes off of the hood is rough on the fan.

With your carbon filter inside and at the top of your room, pull air through the filter and exhaust it outside. Intake for the room/filter fan should be passive intake inside the tent. If you try to use an intake fan instead of a passive intake it is the oposite of the hood scenario where you may presurize your room and push stinky air out.

Pull through the filter and push through the hoods.

Jed

lol im wrong??!? push air threw ur hood and let your lights run for for an hour. "take note of the room temp"

Then set up ur fan to suck the air threw the hoods,wait another hour "take note of ur temp again" and it will be LOWER! now u tell me what works better!
I did hvac for 5 years! I know which way air flows best,and pushing it threw 2 hoods is way less effective than sucking the air threw the hoods!
The whole heat factor on the fan doesnt really matter! i run 2 600's on 1 can fan "SUCKING THE AIR"and the fan still runs the same as the day i bought it 3 years ago!.. The whole point of air cooled hoods is for them to be "AIR TIGHT" they have rubber gaskets on the glass "NO AIR LEAKS"..
and yes u obviously want to suck air threw ur filter! lmao!!!!

GNOME GROWN said:

lol im wrong??!? push air threw ur hood and let your lights run for for an hour. "take note of the room temp"

Then set up ur fan to suck the air threw the hoods,wait another hour "take note of ur temp again" and it will be LOWER! now u tell me what works better!
I did hvac for 5 years! I know which way air flows best,and pushing it threw 2 hoods is way less effective than sucking the air threw the hoods!
The whole heat factor on the fan doesnt really matter! i run 2 600's on 1 can fan "SUCKING THE AIR"and the fan still runs the same as the day i bought it 3 years ago!.. The whole point of air cooled hoods is for them to be "AIR TIGHT" they have rubber gaskets on the glass "NO AIR LEAKS"..
and yes u obviously want to suck air threw ur filter! lmao!!!!

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Well... perfectly sealed is a good hope but I wouldn't bank on it. so you are telling me that if you push air from outside your grow room to the hood(s) and back to outside the grow room with a separate fan pulling air through a filter to outside the grow room with a negative pressure passive intake, the temps are HIGHER than if you just pull it all through one fan? that's bullshit.

Jed

no dude! 2 fans!!! one for the hoods and one for a filter! both pulling air! the one attached to the hoods pulls fresh cool air into the hoods and blows it outside somewhere "not back into ur room" and the other fan is pulling air threw the filter!

Gnome I completly understand what you're saying. I picked up a 4" vortex fan today on ebay for super cheap $55 including shipping. It says it pushes 200+ cfm. I bought one of those 4" booster duct fans from Home Depot several weeks ago thinking that it would be enough for an air inlet supply. I think its like an 80-100 cfm. But now I'm realizing that I should shoot for something around 160-200 just for the fresh air inlet supply. And based by what you're saying I should go for something in the neighboorhood of a 400 cfm fan to pull air through the carbon filter and push it outside? Would another 200-300 cfm fan do just as good? I'm thinking of buying one of those 4" marine fans thats rated at 250 cfm for an air inlet supply. Fuck this is all adding up really quickly! Do any of you know where I can get a pretty cheap carbon filter that would be more than enough for my area? Or maybe a DIY link? I like making shit myself, it saves a ton!

GNOME GROWN said:

no dude! 2 fans!!! one for the hoods and one for a filter! both pulling air! the one attached to the hoods pulls fresh cool air into the hoods and blows it outside somewhere "not back into ur room" and the other fan is pulling air threw the filter!

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So lets say Iuse this method of pulling air through both the hoods and the filter Would it hurt or help if I hooked up a 4" vent booster at the start of the vent to help puch air through the hoods? I don't see really why it wouldn't hurt. I would think it would jus t cause better air flow through the hoods. I'm only saying this because I want to put to use this booster fan I bought from HD rather than not using it at all. What size of an iar supply unit should I use to produce fresh air in the tent? Would a 6" booste fan work for those? Or should I go with a marine inline fan which is rated around 260 cfm but costs about 60 bucks cheaper?

And another thing, I'm gonna make this tent as air tight as physically possible to reduce smells leaking out. Another thing I'm kinda worried about is hawaii 5-0 and their choppers flyig around looking for the heat put off my the lights. Is there anything I can hang in the tent to be as descrete as possible or is it just a gamble. With 2 400w set ups, I'm sure it'll be easily to spot with those damn info red readers the cops are using now days

GNOME GROWN said:

no dude! 2 fans!!! one for the hoods and one for a filter! both pulling air! the one attached to the hoods pulls fresh cool air into the hoods and blows it outside somewhere "not back into ur room" and the other fan is pulling air threw the filter!

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OK, well were not in total disagreement then! We are just talking the difference of pulling through the lights vs pushing. I understand that most fans reach peak efficiency when pulling vs pushing, but I am saying there is a chance of an air leak if you pull through the lamps and the excess heat on the pull end isn't ideal for the fan. The hot air is far easier to move than the cool air so by powering the cooler air that theory kinda washes. Function wise there is probably no difference, but from the standpoint of security and fan life I maintain that pushing is better. Have you actually tried both on your system Gnome?

As for my earlier comment about pulling through the filter that you lmao'd, many people are under the impression that you put the filter outside of the grow and push air through it... doing it right isn't always common knowledge. If you have another reason that pulling is better I would like to hear it.

Jed

2012junkie said:

And another thing, I'm gonna make this tent as air tight as physically possible to reduce smells leaking out. Another thing I'm kinda worried about is hawaii 5-0 and their choppers flyig around looking for the heat put off my the lights. Is there anything I can hang in the tent to be as descrete as possible or is it just a gamble. With 2 400w set ups, I'm sure it'll be easily to spot with those damn info red readers the cops are using now days

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This is from an FAQ in another forum, I have never used this stuff so I can't say for sure if it is as good as stated in this quote, but worth some research to find out.

from another forum said:

C3 anti-detection film:

A specialized type of mylar that exhibits the same properties as the 2mm thick mylar, but in addition to reflecting approximately 92-97% of the light, it also is 90% infrared proof, making your grow room all but invisible to IR scanning. This can also be attached in the same manner as foylon or mylar, and the same caution should be used to avoid creating hotspots in your room.

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For a tent this type of material may not be ideal because it is smooth. I think that most tents have a dimpled texture since the walls are not rigid. I have also heard that "tuff-r" foil faced foam sheathing can work well for IR detection.

Also, as for running two fans on your hoods, that isn't a good idea. If you have 200 cfm at one end and 90 cfm at the other, the larger fan will be slowed by the smaller fan and actually will reduce your efficiency.

If you vent your lights properly you don't need all that much power to vent the tent. you may find that the 4" HD fan can pull through your carbon just fine and get the job done! I would try it before I scrap the fan.

As for sealing your tent well, you want negative pressure on the tent so that any slight air leaks are drawing air into the tent. Get it as air tight as you can (except for your intake obviously) and as long as you aren't blowing air into the tent (meaning an intake fan) you will be fine.

Jed

theres a HUUUUUUUUUUUUGE diff. when u pull the air the fan is pullthe air threw the hoods it makes way less contriction on the air flow! "still pulls cool air from outside the room" vs trying to push the air threw 1 hoods,the air is gunna be bouncing around in the first hood like crazy then needs to go threw the flex line into the other hood then into another flex line and out the room! pulling air on 2 400W lights wont even get over 150 degrees when ur tent is at 80-100 degrees inside!.."as long as you are pulling fresh cool air from outside the room"

i guess its kinda w.e. u wanna do but ive never even ehard of ppl pushing air threw there hoods till this thread!

o yah, but i promis you pulling the air threw your hoods will keep your lights cooler, which will keep your tent cooler!!!

Do not buy an htg growbright fan or filter. Trust me. Get a can. Two fans. One fan for the stank. Filter, fan, then out the top. Another fan pulling air through reflector from outside the tent.

another person for pulling the air vs pushing..lol

Putting your hoods under vacuum (pulling) is a bad idea unless they are 100% air tight. I will agree that pulling through the hood(s) may be slightly more efficient but like someone already said, your taking the chance of sucking odour contaminated air into the hood and out of your grow room for all your neighbors to smell. Whats more important to you, security or most efficient cooling?

I'm a Millwright, I maintain ventilation systems (among many other things) at a nuclear generating station. I've also installed/upgraded ventilation systems in many hospitals. The difference in a (inline) fans performance in either configuration is minimal.