Serious ventilation question

Discussion in 'Grow Room Design/Setup' started by IMC Smitty, Aug 2, 2012.

  1. I I'm going to be growing in a shed with an ac in it. I have the shed split into 2 rooms. My question is, would it be ok to have a vent fan in the wall so it vents into the other room, or does it need to vent outside. And yes i have a carbon filter for it. Any tips/ideas appreciated
  2. I will only be growing in the one room also.
  3. no reason it cant vent to the other room... just make sure that room then has a vent (even if its passive) to the outside, and you need an intake in the room you are growing in from outside, or the other room...

    You cant just blow air out without providing it both a place to go and somewhere to be replaced from.
  4. Would the ac bring in enough new air for that purpose?
  5. yea probably... why are you venting? id just run that A/C as needed. then run your carbon filter inside just as a stand alone recirculating deal. diffusion with the A/C running now and then should keep you in good shape air exchange wise. That would be easier to smell control and cool. Add CO2 if you are worried about air quality, but i wouldnt dump your a/c air out a hole through a carbon filter. no reason to do that.
  6. Venting to control smell. Isn't it necessary to vent?? I've always heard its a must. I live in a town with other houses close by so I need to control the smell.
  7. no need to vent really... i mean you need air exchange but if its a relatively small grow, just being in a shed will allow enough exchange and if you are running an A/C then you will have no issue as far as the plants breathing.

    For smell, like i said just run the filter in the room. Put the intake on one side and exhaust on the other or any way you want to do it so you draw from one side of the room and vent on the other to keep shit circulating... if you get a big enough filter then all your smell problems will be taken care of inside the shed before they become problems.

    If you are doing what you were thinking before and venting with a fan to outside, what you are trying to do is keep negative pressure inside your grow space so no air diffuses out except for through the filter, so you might insure a little tighter smell control that way but things get complicated when you add an A/C... complicated like you will be almost completely wasting your time. If you are exchanging all the air in your room every 5 minutes (which you should be) then your A/C cant really cool, now can it?

    So id scrap that idea and just try to isolate things some... You want a huge carbon filter... like 750CFM air scrubber. couple hundo on ebay. put the intake on the side with the ac... put the exhaust on the other side of the room in the top corner, and put a small passive vent in that area... this should do some to make sure the air that the A/C brings in will force "clean" air slowly out that vent. Follow?

    If you get a filter that can handle your volume every 4 minutes or so I really dont think smell will be a problem.
  8. I think I'm following you. But if I dot have an ac in that room won't the 90+ degree days around here be too much heat? I know heat can induce a lot of problems. Including Hermies!
  9. yes it would be lol... this is why im recommending you keep the A/C but just circulate the air internally through a carbon filter... no exchange with outdoors except the little bit the ac pulls in. What the AC pulls in will have to leak out somewhere right? so you want to sort of help it decide where to leak out by making a 'passive vent' (aka fucking hole in the wall with a dryer vent cover on it) up at the highest point you can reach. then, since its going to just slowly leak out that hole as you run the AC, you want to make sure that the air leaking out is as clean as possible... so draw air from as far away from the hole as you can through a carbon filter with an inline fan, and vent that air inside the same shed, up near the hole you made. this way you can clean the air in your grow every 5 mins as desired, but without pushing all the air outside every 5 mins... the A/C running will exchange that air much much more slowly and allow the temps to stay well below the ambient temps outside.

    like i said, as a trade off, you want to make sure you overkill your carbon filter system because nothing stops the air from leaking slowly all around your shed. you want the air that leaks to be squeaky clean!! so get one that will process your air every 3 - 4 mins.

    what carbon filter/fan do you currently have that you were going to vent with?

    if your area is say 10' x 12' x 8' you would have 960 cubic feet of air so you want like a 400 CFM fan and a carbon filter that can handle it... or better yet this one:
    New MTN Hydroponics 8" Inline Duct Tube Exhaust Fan Carbon Filter Kit 745CFM | eBay

    if you run that in your shed, and do passive vent out the top with AC on, you will have no smell issues and will be exchanging enough air for the plants to have CO2... and you can always add CO2 to the grow if you think thats not enough air exchange (but i wouldnt worry about it)
  10. Ok I'll def look into that. Thanks for all the help!

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