Carbon Filter not working?

curious101

Well-known member
So i purchased a carbon filter (a growbright 4in. Jr. Carbon Filter) and a 6in. inline duct fan with a rating of 160cfm free air flow (250cfm booster flow) inside a grow tent that is 39inx39inx79in. I've got the 6in fan mounted on the top of the tent, then attatched a 6in to 4in. duct reducer and applied flexible aluminium ducting (used commonly for clothes dryers)...i've read that in order to properly filter air you multiply the LxWxH and divide by 5 (air must be exchanged every 5minutes minimum) which means i'm roughly at 63cubic feet...divide that by 5 and you get 12.6cfm roughly...i've assumed that the 3 vents in the bottom of my tent would provide enough air in the bottom for the proper exchange, am i wrong? Also, in a day or two if necessary I will be putting some ducting on the outside attatched to a 4in flange on the bottom to allow more free air into the bottom of the tent...any idea on why i'm having troubles controlling the odor...i've linked below the products i'm using and would appreciate any and all input
http://www.htgsupply.com/viewproduct.asp?productID=53376
http://www.htgsupply.com/viewproduct.asp?productID=46447
http://www.htgsupply.com/viewproduct.asp?productID=49749
 
That fan is not going to cut it. You need a fan that won't bog under a load. That fan may be 150cfm with no ducting bends of filter, but after you add those restrictions, it is not pulling the air over the carbon fast enough to scrub it. A 4" centrifugal type (vortex, fantech) will work for your filter. I have a 4" vortex, and a 6", and I LOVE them. :) Worth every penny. The vortexes blow hard and loud, so consider a speed controller or a muffeler.

Those fans are boosters for long runs of ducting (like venting runs of lights, or for intake).

EDIT - Here are the best prices that I've found for the vortexes
http://www.plantlightinghydroponics.com/vortex-inline-fans-c-76_352.html

Here is a cheaper fan of the same style. I can't really recommend these, as I've never seen em, and if they fail you are prolly fukked in a tent.
http://www.plantlightinghydroponics.com/valueline-centrifugal-fans-c-76_629.html

I like that site, but they sent my filter in a retail box. If you use them, request plain box shipping if that is important to you. :)
 
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well i went to check everything...i tried to make the ducting as straight as possible and shortened the length a bit, checked an hour later and the smell is gone...weird last nite everything was working great but today some of the ducting loosened up (i'm sure it will a bit for a few days as i didn't want to pull it too tight and rip anything causing leaks) so i used an extra bungy cord to hold everything straight and it seems fine...i keep checking it and everything seems fine so i hope things work out and its dependable, i did a smoke test with a cigarette and it was really pulling the smoke in fast so i hope it works out...thanks for the help barletta and when i have the money i'll get a much better fan like the one you've suggested...any other advice? Whats the difference between the 160 free air flow and 250 cfm booster rating mean, when i ordered the fan on the site it stated 250cfm but the box says 250*booster flow and 160 free air flow?
 
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I'm not sure, but I think that the 160 rating is 'no resistance'. The 250 rating is a make believe # assuming that there is centrifugal or dayton providing most of the airflow, and the 'booster' placed inline.

EX: I intend to use my 6" to push air through 6" ducting and 2 6" air cooled hoods. If I had a long ducting run (~20'+ total ducting run) either after or before the lights, I'd probably add a booster fan. As it is, I bet this vortex would have little problem with 20' and few bends.
 
I'm not sure, but I think that the 160 rating is 'no resistance'. The 250 rating is a make believe # assuming that there is centrifugal or dayton providing most of the airflow, and the 'booster' placed inline.

EX: I intend to use my 6" to push air through 6" ducting and 2 6" air cooled hoods. If I had a long ducting run (~20'+ total ducting run) either after or before the lights, I'd probably add a booster fan. As it is, I bet this vortex would have little problem with 20' and few bends.
awesome info...thanks for the quick response....if it holds up for a few days due to my med condition and inability to work i'm gonna just leave things be, as the old saying goes if it ain't broke don't fix it...if not i may just wait until i get some more $ saved up and buy a good fan, i should did more research but with a very low budget i had to cut corners a bit and the fan was 1/4 of the price of the high output fans...i normally just grow without any carbon filters (over 3 years) but wanted to try some high odor strains that i've often strayed away from...i've got two MangoWidow keepers i just don't want to let go but one is HIGH HIGH odor so i may have to let it go if the fan fails, but the low odor one is much more narcotic anyway so i wouldn't call it a loss...thanks again
 
No prob c101 :) I'm sure that fan will give you 25 bux worth of use. I'm thinking now that I could use a fan like that just to exhaust air from my veg room. I was going to but a 2nd 6" to vent the lights, but I bet I could vent the lights with my 4" on a short run (I have a reducer already), and keep exhausting flower with the 6". That would save me a few bux. Thing is, if I had the exhaust fan fail in veg, I'd be fine. The temps would go from 65 to 72, lol. After recently dropping a cheapo ballast, I'm resolved that I won't buy any cheap equipment that will screw me if it failed. I'll use grow bags, and drug store circulation fans, but from here out, it is quality magnetic HID ballasts all around, and overkill on the exhaust/odor control. I'll use vortex fans until one fails or they change the design significantly.

LOL, I was tearing down the framework from my 'closet' today, and I found the 2 $10 rite-aid fans that I ran with for the first year. Go breezemaster! I'm re-doing my room, and if I can't get the ballasts out, I'm going to turn the breeze master on em :)
 
i'm just wondering if the 4in. would cut it as its rated at 170cfm and my inline is 150cfm...i'm really leaning towards working something out to get a vortex fan...the 6in with the 474cfm would be far to strong and i'd have to add a speed control...i'd rather have more than enough ventilation as i can always reduce but it can't be really added to...i've got an extra 4in. inline rated at 60cfm and i'm just wondering if i combined the two cheap inline fans if everything would work out...i really fucked up and shoulda asked more questions, as it seems this fan works OK but an occasional wiff of pot can be smelt if you get close to the tent and its very irritating
 
Get the 4". I was exhausting a naked 400w CMH bulb, through a hood with a 400w hps in it, then the 4"vortex and I had an odorsok (junk for growing, would prolly word in a short term 'drybox') on the outside. Space was ~6'L x 2.5'W x ~5.5'H, and temps were ~10-15 deg above ambient. Plants LOVED being jammed in with all that light and mylar... Even the 4" w/o a controller will be a lot of air flow for a tent, so consider a controler down the road. The passive vents on the bottom will suffice for an intake, and if you can, consider filtering the intake. I'm dealing with PM right now, and the spores got in there somehow...

Also pick up a jar of ONA gel and a bottle of liquid (prolly 30-40 combined, I use the big bukkit and bottles @ ~50 ea). I put out little dishes (lots of little dishes when that odorsok was failing, lol), and it kills the smell of weed smoke, dogs, and 'single guy'. Plus I don't use the electricity on the plugins (~$1 per month, lol). I use the ona on the outside of outgoing 'packages', and I have the bukkit open in my dry room when I use it.

Bro, I've been growing ~18mo, and I've wasted tons of money on crap! LOL, it evens out when I consider that my bloomroom (3 x 400, 6"vortex, filter, boxfans) cost under $1g, and makes that back for me monthly :) Shit, my first flouro room ended up costing me over a G (and a nice fukkin scar from chopping fiberboard, high as hell with my SEAL knife...) when all was said and done. You will end up using that fan somehow, and LOVE the 25 bux...

Yeah, get the 4" vortex, I love mine!

EDIT- try like hell to mount the fan so it draws (pulls) through the filter, as opposed to blowing (pushing). The reasoning is that the air will pass over a greater surface area at a higher velocity. It will be more effective scrubbing the smell. I have had mine set to 'pull' since day one, but I have lots of room to play with. I saw that filter, and it is kind of small (4lbs of carbon?), imo. It is possible that it's too small. Mine is 44 lbs of carbon, but is overkill. I bet I could go to ~2500w with that filter and the 6"vortex. Think I'll try :D
 
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Now that is funny...I bought the same fan and carbon filter combo...silly me. Now I just have a carbon filter that relaxes on the concrete and that fan hooked directly into one of my lamps reflectors.

Adapt and overcome.

I have however always wondered how well the negative ion generator thing thingers work???
 
Now that is funny...I bought the same fan and carbon filter combo...silly me. Now I just have a carbon filter that relaxes on the concrete and that fan hooked directly into one of my lamps reflectors.

Adapt and overcome.

I have however always wondered how well the negative ion generator thing thingers work???

well good to know i'm not the only one...i'm wondering what the return policy is on carbon filters as i'd like to replace it with the filter with about8lbs of carbon (only an extra 20$)...i'm working on a new set up and we'll see how things go...thanks again everyone for the advice
 
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