Venting closet

[JDJP]

So I have been a member here for quite a while, and have spent a lot of time browsing many threads and journals, and have learned almost all of what I know from various people on this board.
That being said I have tried searching and have had trouble finding answeres to my problem. So im going to ask you guys.

Alright so the grow space is 4x9x8'tall, there is 1 400 watt hps with air cooled hood with glass, and a 4" (I think) 60cfm inline duct fan sucking air through the light and out into the next room. Also I have a box fan blowing air over the light.
I have a thermometer level with the top of the pots and it reads between 85 and 90 but goes down to around 80 if I put the thrmometer on the ground.

I have been trying to place the fans different ways to try and cool it down, but it doesn't work.

I have been keeping a fan in a window in the connecting room and keeping another window cracked to get some flow through. But it is quickly becoming to hot, and will have to turn the AC on very soon. There is a small AC vent in the closet, and an AC return in the next room within feet of the closet.
I have the 4"duct from the light blowing directly into the return right now with the AC on, but the thermostat is on the other side of the house and the room is still to hot.

So now that you have a little backround on my sutuation My question is How do I keep it cool in the closet while getting fresh air in there for the girls?

If I bring fresh air in from outside it will cancel out the AC, If I keep my windows open it will get too hot.
What are my options?
Help would be much appreciated

P.S. I planned on buying a 400w MH, and a good 4"fan in the next couple weeks.

JD

 

[Be Irie]

I think that 60 cfm is not enough, you made to atleast double that, and use the 60 to exhaust hot air from the grow room. You should get an intake fan to bring the cold air in from the other room.Exhaust high, intake low and put a little fan blowing the cold air at the plants... Not only do you have to get the hot air from the light, but also the room...

 

[JDJP]

ok so Im going to throw a few Ideas out there, just cause its bothering me sitting here thinking about it.
I can cut a hole in the cieling and run duct out to the soffet and have a vortec fan pulling air through my light(s) and pushing it through a carbon scrubber and out an attic vent. While another run of duct pulls air from another attic vent as a passive intake. But what about when the outside temps reach into the 90s and even 100s this summer?
and that option will cost around $300. unless I make the carbon scrubber meself, do the homemade scrubbers work well?

Another option get a window mount AC unit, and a CO2 generator, which I know almost nothing about. Cost? either a burner type, or a bottle type. I know with a burner type it makes some heat which would cost more in elec., but I would have the central air off during the day, and the window unit keeping just the room and the closet nice and cool. The bottle type costs more per cubic foot to refill than you burn in propane to make it. plust Id have to go refill a big CO2 can all the time.

Thats all I can think of to get off my mind, hopefully someone has posted by now

If not, Don't let my rantings Keep you from giving your opinion

 

[JDJP]

I think that 60 cfm is not enough, you made to atleast double that, and use the 60 to exhaust hot air from the grow room. You should get an intake fan to bring the cold air in from the other room.Exhaust high, intake low and put a little fan blowing the cold air at the plants... Not only do you have to get the hot air from the light, but also the room...

Thanks for the reply
but then what do I do about getting fresh air to the girls?

 

[JDJP]

I have been searching since I made this post and have found no answers.

So obviously when we are sitting at home in the AC there is fresh air leaking in from some where. The AC isn't just recycleing the CO2 we are producing over and over, or we wouldn't be able to breathe.
So if I vented into the attic with a 400 cfm fan, and left the door open to the next room, the negative pressure would suck on the AC vent and under the other door, therefore my passive intake would be the whole house, where the air usually leaks in and out. And the central AC would just have to work a little harder keeping the new air cool. Would this work as a very highly diffused passive intake?
How big (in cfms) would i have to go with the fan for this to work? it also has to push that air through the carbon filter

 

[bog420]

I have been searching since I made this post and have found no answers.

So obviously when we are sitting at home in the AC there is fresh air leaking in from some where. The AC isn't just recycleing the CO2 we are producing over and over, or we wouldn't be able to breathe.
So if I vented into the attic with a 400 cfm fan, and left the door open to the next room, the negative pressure would suck on the AC vent and under the other door, therefore my passive intake would be the whole house, where the air usually leaks in and out. And the central AC would just have to work a little harder keeping the new air cool. Would this work as a very highly diffused passive intake?
How big (in cfms) would i have to go with the fan for this to work? it also has to push that air through the carbon filter

you are describing my exact setup. i live in florida, and would have the same issues with outside air. use your house for the passive air intake.

i am running 2 400w mh air cooled hoods and am venting 96 cubic feet of grow room. i use 6inch exhaust duct from the box into the attic and have a 400 cps can fan blowing into a can66 carbon filter. for intakes, i am using 2 - 4 inch ducts (light proofed) directly to the outside of the grow cabinet. the cabinet is hid in a closet by slatted bi-fold doors, so i pull plenty of conditioned air in from the room.

temps stay in the 75 degree range directly at plant hieght. no issues at all.

good luck - bog

 

[JDJP]

Thanks bog
I feel better already