<P>Hey everyone..420 is gettin closer<IMG alt=0 src="http://www.rollitup.org/images/smilies/piped.gif" border=0 smilieid="208"> !! but anyways i have a closet which is 3'x4'x7'. the walls are covered in a reflective tarp material i got from local garden store. The opening to the closet (door) is covered in this material&nbsp;on the inside as well to keep light from escaping. The door is a two piece door that opens from the middle. Not sure if i am cuttin holes in the door for ventilation but i need it so u cant see the fans when u are standing in the bedroom. please help would be appreciated! if yer confused at all let me know thanks!</P>

First of all is this your place? Can you do a little poke a hole here and there?

oh yea and i will be using a carbon air filter for exhaust

its not my place but where and what size hole u talking bout? lol

A 4 inch round hole one up high and one down low. The low one intake high exhaust. You can figure out where would be the best placement for you. Check out this site:

Suncourt Inductor In Line Duct Fan - 4 in.: Allergy Relief Superstore

This might help also:

contributed by :Rouhea
submitted June 9, 2003

How do I install a duct fan to operate most efficiently?
(principles of effective ventilation)

Many growers own fans powerful enough to move air of a city block in Manhattan, but has failed to install it properly, causing greater pressure reduction. This extra pressure drop is called the system effect or system dissipation, and can cause the fan to produce a smaller volume of air than indicated in the fan diagram.

The following factors must be considered in order to avoid system dissipation:

At the Inlet

The distance to the nearest wall must be more than 0.75 the inlet's diameter.
The inlet duct's cross section must not be greater than 112% or less than 92% of the fan inlet.
The inlet duct's length must be at least 1 x the duct diameter.
The inlet duct must no have any obstacles to the air flow (dampers, branching or similar).


At the outlet

The angle at the reduction of the duct cross-section must be less than 15 degrees
The angle at the enlargement of the duct cross-section must be less than 7 degrees
A straight length of at least 3x duct diameter is required after a duct fan.
Avoid 90 degree bends (use 45 degree)
Bends must be shaped so that they follow the air stream after the fan.

If the connections are different from this, there could be a greater pressure reduction.




Circular duct fans for example, are propulsive, pushing the air. And should be installed so that the long duct is after the fan itself.

thanks for that info but i know about the inline duct fan and thats one of my options but i need a way to be able stealth out the fans or make it look like they arent even there..any ideas?

You mite think this is stupid question but why do people run carbon filters in such small grow areas ? my closet is about 5x5x7 well vented and you can only smell weed if you enter the room . I would have though it not necessary for small ops but i dont know your conditions

I don't find it necessary to run a carbon filter either. Same as you can only smell it when you enter the room.

If you don't want anyone to see the fans or vents place them just inside the doors put at the top and bottom where there are gaps in the doors. That way they can still draw and exhaust the air. I don't know your set up but do you think that would work for you?