Air intake/ exhaust problems

[blowinsmoke]

Here's my problem. I have a room that is about 6'x8'x9'tall. I run two 600w hps. My temps are really high and it's winter here now. I'm running a 8" inline exhaust fan while the entire time the lights are on. It is in the ceiling running to a vent in the roof. I can't remember the cfm, but it is a lot. around 700. I'm using a 4" inline intake fan. it runs the entire time my lights are on.

A couple days a go I built a cool tube for one light and hooked the 4" fan up to it. That helped a little but I still can't close the door on the room without the temps going to 100 degrees by the end of the day.

Any one have any links to ventilation setups or good ideas on how to fix this problem. Thx

 

[pcduck]

need a bigger intake

 

[Motor City Madman]

Try taking out the intake fan and cut a hole twice the size of the exhaust fan. This is called a passive intake, place it as low as possible. I sure your 8" exhaust is straining the 4" intake fan.

MCM

 

[blowinsmoke]

Do you think I could intake the air straight from the crawl space under my house? If I do that, what do you think would be the best way to keep bugs out?

 

[pcduck]

If you have a lot of bugs in your crawl space, you better check your foundation.
But furnace filters work for big bugs, aquarium floss, ect

 

[Motor City Madman]

Yes you can. I would use a window screen on my intake though.

MCM

 

[blowinsmoke]

I have an ant problem mainly. Had it forever. All over the property. I'll start tomorrow. Thanks.

 

[blowinsmoke]

I wanna ask something else. I've been doing this a while, but never really had a chance to ask many questions. Learn as I went thing. I measure my temps at the buds closest to my lights and try to keep that around 85 degrees.

 

[Motor City Madman]

Unless they are micro ants they wont get through a window screen. You might want to make it a little bigger to compensate for the restriction of the screen. It is all about balance, once you find it you will be surprised at how efficient it is

 

[Motor City Madman]

you wanna be between 70 - 75 deg and 30-40 humid

 

[blowinsmoke]

Cool I've a lot of window screen material. Between ceiling height and the height of the system I use I've never been able to stay that cool. I struggle to stay under 100 degrees.

 

[Motor City Madman]

That is way to hot you need to consider air cooled hoods for your lights this will help dramatically.

 

[blowinsmoke]

I hear ya! I built one of those cool tubes yesterday. I hooked my 4" intake up to it. That helped, but not nearly enough. Plus it cut off all the air I was bringing in. I wanna do both I think. Cool tubes and the passive cooling.

 

[Motor City Madman]

I run a 400w cool tube with a 6" fan and a 6" exhaust fan and passive intake my cab is 74 deg lights on 70 deg lights off.

 

[blowinsmoke]

It was 85 degrees 12 inches below the light with the door open using the cool tube set up. It went to 90 when I closed the door. It's a really frustrating situation. I appreciate the help though.

 

[pcduck]

If you have a cool tube. You are not setting it up right with those temps.
are you drawing outside air into and through your cool tube? Are you exhausting this air out of your room?

 

[Old Hippy Toker]

Helped with a room the other day-They run 2 each 1000 HPS and two each (twin ballast) of the 600w HPS in a room that is 8x8x9 with propane generated
CO2. That sounds like it would be too hot in there BUT they have a 12" intake and a 12" exhaust. the room maintains 74 to 85 degrees with humidity at 40 to 60%. If ya do the math thats 3200 watts of nice bright lite with no heat
problems...yes, BIGGER is better when it comes to intake and exhaust.

 

[NewbieG]

Do you think I could intake the air straight from the crawl space under my house? If I do that, what do you think would be the best way to keep bugs out?

I've read in a book of people doing this and its a great idea AS LONG AS the air under your house is contaminated with mold. Remember dark and damp places are perfect homes for mold.

If you really want to fix your problem you should use all the suggestions you've heard. Remove/ upgrade to a larger intake or you could just pull that cool air from under your house passively for your air, then just use a double cooltube open to the room on one end and being vented with the 700 cfm fan you have. I really can't imagine your temps being too high after this, but if they are, you could either bring in the CO2 which I would highly suggest because I've heard great results, or just buy a window AC to turn on every time the room gets too hot...

 

[Old Hippy Toker]

Mold spores are almost everywhere. If you do too well and your buds are huge (what a problem, huh?) you may get mold or mildew even if your air movement is sufficient. I use a spray in the last few weeks and it prevents mold all the way to the center of the bud-great stuff.

 

[blowinsmoke]

Well I spent the last two days changing my intake set up. I'm using an 8" inline fan to exhaust it is in the ceiling and vents out the roof.
I have three cool tubes set up now. Each has a 4" 80cfm fan pulling air from the crawl space. I also cut three 5" passive holes in the floor.
One light is a lot lower then the other two. About three feet. The temp on that light is great. 70-75 degrees. The temps on the lights close to the ceiling really haven't went down much.
Now I'm wondering if I'm not pulling the hot air out of the room. When I go in the attic I can feel the warm air inside the exhaust pipe.