Ventilation question

[tito13]

Hi, i have a closet, 8x11, i have the plants in one end, and the window is at the other end, i close the door in the closet and leave the fan in the floor pointing towards the plants( oppossite the window), 9" fan; but still i go in there, and its so humid, like the air is not going out the window. Now, How do i set up my fan or fans, so that the air can circulate better? Should i point the fan towards the wall above the plants so that the air can bounce back towards the window?? Thanks.

 

[stonedrone]

You want a fan to pull the air out of the room and some sort of vent to let air in plus a fan to keep air circulating. Think if there is only one way for the air to go there is no where for it to come from or vice versa, so...one vent equals no vent.

 

[Tater]

You can't remove air from a room without replacing it from somewhere. Whats happening is you are trying to push air out the window and it doesn't work because there is no air comming back in from a vent and thus you create a vaccum, or you are trying to push air into the room from the window and can't because you have now created a possitve pressure system, its kinda like trying to put more water in an already full glass, it just doesn't work.

So you have two options here, cut a passive vent somewhere so that you can push air out the window and have it sucked in from somewhere else, or you can split your window in two by building a box around it with a divider on it.

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Kinda like that, then you install a fan pulling air in on the right side and a fan pushing air out on the left side, use ducting to get your fan that is pulling air in as far from the box as you can and still maintain good airflow and install the exahst fan right in the other side of the box, or use ducting so the exahst pulls air from the top of the room as this is where the most heat will be. By spacing out the fans like this you avoid sucking out the fresh air as soon as you push it in and force it to cycle. This way you don't need to chop any new holes in the room and can just pack up and leave without any damage when you are done.

Good luck.

ASCII art ftw

 

[willowgrow]

Hey.. sorry to jack this thread a little but I too am in the process of setting up my ventilation for a new grow. I have what may be a stupid question: should I be worried about smell leaking out if i have a passive air intake with a 6" carbonscrubbed/canfan pushing air out?

 

[tito13]

I think i got it. Thanks. I will look into it. So, a fan will suck air out, through a duct place it towarts the top, and the other push air in, from a duct at the bottom, but thay can both be place in holes from that one window. brillient!

 

[Tater]

@willow, so long as your fan is pulling air out and through the carbon fan faster than it can be replaced in the room you will create whats known as negative air pressure or a vacuum, this will stop air from leaking out of the room because it is always trying to suck in air rather than expel it. You shouldn't push air through your filter, rather you should place the filter in the room up high and pull air through it and then out of the room, this is the way the filters are designed to be used. To be doubly sure that you have no smell leaks, line the room in poly and seal all seams with technical tape or aluminum tape NOT duct tape, duct tape sucks, it is not designed to be used as a vapor barrier tape and this is essentially what you are trying to create more or less. Technical tape, also known as tech tape is THE best tape you can use for this application and is sold at all hardware stores, it is usually red and somewhat see through, just ask the dude at the counter for it. Tell him you are siding your house and need something to seal the vapor barrier or just tell him to shut up and mind his own business, lol the latter will most likely cause you more problems and suspicion than just being nice.

@tito, if you want your port box (this is what the box is called you will build) to be more stealthy what you can do is construct a box that is bigger than the width of your window by one foot on each side and make it about a foot or two deep, paint it a non reflective colour like black or whatever you think will be the least noticeable. Cut your vents on the sides of the box so that they can't be seen when looking at the window straight on. Hang this from the roof with sturdy chain and hooks designed to handle the weight. Then create a seal around the edge of the box using tech tape or whatever you have available, make sure it is air tight, also be sure that both sides can't share air or leak into one another. Just a heads up if you put tech tape or pretty much any strong bonding tape on your walls it will remove the paint/wallpaper or whatever when you try to take it off, you could make a sealed room like I outlined above and tape it to that instead to save your walls but thats your choice. This way the vents and fans are hidden from the outside.