# Help with carbon filter placement



## Killertea08 (Jan 2, 2016)

Hey everyone just about ready to finish up my stealth cabinet.  My cabinet is 40"x20"x48" vegging with a 2ft 4 bulb T5 and flowering with a 250w HPS cool tube from "The Hemp Goddesses" design.  So I could exhaust the light and carbon filter at the same time but the 4in ducting would get bent all around, but it could work.  Or option 2, I have a 110cfm axil fan to dedicate cooling my lamp and the 4in vortex fan only exhausting the filter, which would clean up the space.  Ok opinions?  

Pictures to come


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## pcduck (Jan 2, 2016)

axil fan will not do the cooling. Fan is made to boost air that is already moving.

Place filter outside of grow space?


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## Killertea08 (Jan 2, 2016)

The axil fan pushes 110cfm and would be dedicated to cool the cool tube 250w hps only.  The 4in vortex can do both yes, but it wouldn't look very clean with all the 4in ducting.


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## Killertea08 (Jan 2, 2016)

Pc duck can I put the carbon filter outside?  Doesn't the fan run more efficiently if it sucks vs blows lol


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## hippy59 (Jan 2, 2016)

im using a 6 inch axil fan to pull the hot air out of my 1k fixture and it seems to be doing nicely but I've pulled the exhaust line fairly taught with only 1 45 degree bend. i'm in a 5x5 tent.

yes you can put the filter outside the cabinet. just make sure there are no air leaks.


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## Killertea08 (Jan 2, 2016)

Thanks Hippy, oh and my carbon filter was a diy that I never used, should I replace the carbon?


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## Killertea08 (Jan 2, 2016)

Here is a picture if what I have so far. 

View attachment 2016-01-02 17.42.03.jpg


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## Killertea08 (Jan 2, 2016)

With the light on 

View attachment 2016-01-02 17.48.35.jpg


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## hippy59 (Jan 3, 2016)

it should be ok for a few years of non use at least. mine ( a smaller one ) was good after siting for over 2 years.


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## pcduck (Jan 5, 2016)

I need all the room there is in my 4x4, so my fan and filter is outside the tent.


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## Hushpuppy (Jan 5, 2016)

The vortex and other "centrifugal" fans build pressure when they run because there is very little to no space for air to bypass the fan. This builds negative pressure on the suction side of the fan and positive pressure on the output side of the fan. If you don't have the room inside the grow space, you can connect the filter to the output side of the vortex fan (I have 2 of these) and the input side to the cooltube, either directly or with flexhose. Most of the carbon filters on the market today will work in either direction but seem to be generally better when the air is drawn through from the outside. But for smaller operations, pushing the air from the inside should be fine.

Ideally it would be better to set it up with the fan and the filter on the inside where the inside air can be pulled through the filter first then pushed through the lights and out. But the grow space often dictates this setup. I used to have my tents set up with the fans 10' away from the lights and filter, with the filters being inside the tents I was using, and it worked quite well as long as I had good passive intakes. There are multiple ways to do it, just make sure it eliminates the odor and keeps the proper temps. With the vacuum pressure that is generated by the centrifugal fans, having multiple bends in the flexhose is less of an issue as the vacuum pressure can overcome the turns. I am sure however, it does slow down the air flow somewhat. It then becomes a matter of how much is it slowing it down. For a smaller system, its probably not much of a factor.


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## The Hemp Goddess (Jan 5, 2016)

I would say that we should address this issue when you get to the point that you need the filter.  Do not connect it until you need it for odor control, which will be 2 months or so down the road.


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## hippy59 (Jan 5, 2016)

I guess it depends on a lot of factors. everyone is correct but there is no set way to do it. I have more then 1 tent and don't want to buy several expensive fans and filters, so I use the axial. HOWEVER, I DO use my big fan mounted to the filter in the HUGH room I have and vent it out of the room, thus making sure I have odor control by keeping my whole room under a vaccum. so far as heat removal goes for my tents tho the axials do fine. so far. hope that clears things up. I did try just running the filter and big fan and let it recycle in the room but I still had odor issues so I vented out of the room and its perfect till the filter wears out.

  and tho I have never done it, I have a friend that pushed the air thru the filter instead of sucking thru the filter and it worked for him. he had room issues like you did. just make sure you tape up all the joints.


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## Killertea08 (Jan 6, 2016)

Thank you everyone, your experience  and advice is greatly  appreciated!


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