My Growing Closet Setup + Sound Control?

Cool tubes work best when they are run separately from the room extraction like this....



There is no intake fan, air is drawn through vents around the bottom of the tent (you can see one in the background) passively by the partial vacuum created by the exhaust.

Is it getting so hot because of the half-open cooltube and will be OK when I add the filter and ducting on the other side of it?

No, it wont get better by sticking a carbon filter on the open end of the cool tube... it will probably get a bit hotter as the carbon filter will slow the air movement further.

Originally posted by assinomen In physics the principle of the exhaust fan is that it pulls air better than it pushes

Where there is significant resistance it makes sense to pull, rather than push, air eg. I have my centrifugal fan set to pull air through a carbon filter (high resistance), but have my inline fan setup to push air through the cool tube (low resistance) to reduce noise at the outlet and so the hot air is not run through the fan.

Placing the fan close to the air outlet will magnify the audible noise on the far side of the outlet.
 

Thank you sarah louise and assinomen!

I prefer to have everything inside the closet, both for stealth and for less noise, so I guess I'll leave my exhaust inside, only reposition (and box) it... :) .

After your recommendations, and after seeing the current temps in the closet test I ran, it does seem  much more reasonable to setup the bathroom 4" fan just for the cooltube cooling. Too bad I was advised by my grow store to set it up like that... oh well, not a big deal.

My only new problem is this: I now will have a 4" hole in the left bottom of my closet, just open... You guys advised me to have 2 passive intakes twice the size of the outtake so that means I should have two 8" holes as intakes in the bottom of my closet?
And how will I prevent light and all sorts of bugs from coming in through those open holes?
Is it really necessary to have two 8" passive intakes in my closet, in your opinions and from your experience which I lack of?

Thanks again!

Originally posted by kph1966 In my temporary grow area i pinned nylon socks over the intakes to help with light entering and to stop critters also getting in and actually gave them a couple of layers which did a pretty good job. The biggest problem that i am having is that i expell my air straight outside and when it comes to cooler weather this could be picked up by by thermal imaging cameras so i am trying to devise some kind of heat management into my out-take. Good luck and have a good weekend.

Thanks!
And that nylon sock doesn't slow down the air from coming in/out?

I will expell my air to the same room the closet is in, so I don't worry about thermal picking, though I'm a bit worried weather this will change that rooms' climate, like make it more humid and hot...? But I hope it will be fine...

boilers etc  kick out heat plumes i dont think the thermal eye in the sky will be looking at that   ,they are looking for large areas of anomlous heat from the lamps themselves.
there are plenty of ventalation systems kicking out heat .i did a piece on venting through your chimney breast, if you have a chimney breast for a fireplace they usualy have a plastic flyscreen,you can take this off and put your exhaust duct out of that.
depends where you are in the world ,most house/apartments have a flue system for gas fire,s and in older houses a lot have been blocked,but they have a plastic air vent for fresh air circulation.so you can put your flue out of that. its natural for heat to come out the chimney stack on the roof,and its that high up the wind takes the smell away 50feet up in the air.if you have a gas fire you would have to disconnect it and you could connect your duct with the duct at the back of the gas fire.if you have an old fashioned fire place you can get into that ,via the covering board or vent/flyscreen.you dont want to recirculate ex gasses out the tent and back into the inlet duct..have a survey of your room and see if there are outlets to the chimney etc.let me know the layout i could tell you he best option  i spent my whole life as a builder so know the internal layouts of exhaust ducts ,or take a few pics and post them .maybee i could help..  
most apartments/houses have internal ducts to expell fire fumes/air con etc if you could describe your room,i could advise you where to get the ex gas out sometimes you can go through the ceiling into the roof space,but you have to vent it out from there.ppl have been busted cos of mould forming on neighbours ceilings.if you check your room for fresh air vents etc post some pics.i did a explanation on "ventallation through chimney"search for that in ..indoor growing...
if you exhaust out of your tent into the room the exhaust gas will be sucked back into the inlet pipe.even making a box around a window/blacked out with the exhaust fan at the bottom will dispell the ex gas out the window, the thermal image camera will not see this as weird,otherwise every house in town would be raided..