Why the @#$^ can't I get my temps down

[baddru]

Room is 11' x 11'
2 600 watt HPS bulbs hanging vertically over a 4' x 4' table
465 CFM squirell cage blower
I have built a sealed box around the basement window nd the window is open
Outside the room the air temp is 70 F
There is a fan blowing straight up from under neath the lamps and the 465 exhaust is right above that

I have tried

1 connecting the fan to the box to vent the air outside while pulling air into the room from the 70 F basement

2 connecting the fan to the box to vent the air outside while pulling air into the room from the veg room next door

3 connecting the fan to the veg room next door and pulling in air from the 70 F basement

4 connecting the fan to the veg room next door and pulling air from the 80 F outside

5 installing an 8000 BTU AC in the box that is around the sealed window and leaving the exhaust fan off

6 installing an 8000 BTU AC in the box that is around the sealed window and leaving turniing the exhaust fan on for 15 mins every 1 and avery 2 hours

I CANNOT get my temps below 95 F in this room. WTF???

Please any help or ideas are mucho appreciated. I have considered taht my thermometer is broke, but it is WAY warmer in this room the moment you enter from the nice cool 70 F basement. It seems like blowing the air out the window while drawing air from the cool basement would take care of this. Especially since the fan is so large for the room size. When I go outside and stand at the window, I can feel vary warm air being exhausted even though it is already so warm outside.

 

[dongle69]

You need more cfm.

 

[baddru]

really? for only 1200 W in a 840 CF room. (7 ft ceiling) I thought air exchange should be about once every 5 mins. I've got it less then 2 mins. How come even with the AC its not cooling?

PS I've read your whole 6 K room. Its a real inspiration. And I can see how much you love CFM.

 

[Possumtail]

The only thing I can think of other than running your lights at night is that your thermometer is picking up the heat from your lights. Try moving the thermometer to a corner of the room or by the base of your plants if their decent size and see what it says.

Sorry couldn't be of more help. let us know how it goes

 

[smokinshogun]

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[dongle69]

You need to move a lot of air to not only cool the room, but to cool the lights.
If it is 80 outside it will be tough without completely sealing the room and using an efficient a/c.
You could then use the fan to to cool the lights with sealed air cooled hoods.
If your basement air is 70, that is your best bet without a/c, but you will need at least double the cfm (in my estimation).

 

[baddru]

Yes the therm is right under the lights, but I do have another fan blowing over the garden to keep air movement.. The fan blows pretty much right on the therm. Will I get an accurate measurement of the air temp with the therm elsewhere in the room?

 

[baddru]

The room is noticably warmer then the basement. I will move the therm to another location to ensure that it is not just the IR making it so high. However my plants do have a lot of what appears to be heat problems and burning. Many many leaves are completely brown to white from the tip back to about half way, while the rest is still a nice green. The plants are on the outer perimiter of the 4 by 4 table with the bulbs hanging vertically in the middle. is 18 inches too close to the lamps?

 

[alpinestar]

use an exhaust fan with a charcoal filter with a humidity and temperature controller

use a 2nd fan to draw outside air through light hoods and back outside the grow space. this fan would just be connected to the same timer as the light

you also need an oscillating fan to circulate air in the grow area

if temps are still unacceptable, then get a larger exhaust fan

 

[baddru]

I do not have light hoods, as this is a vertical grow. I will be going back to horizontal with hoods after this cycle is complete. There is an oscialating fan blowing over the garden, as well as a powerful stationary fan blowing straight up over the bulbs and right into the intake of the 465 CFM exhaust. Sounds like more CFM. I just don;t understnad how if the air is already being exchanged every 2 minutes and the incoming air is only 70 F how it gets to be 95 F in there. I will be moving the therm first thing tomorrow after the lights are back on and seeing what kind of reading I get there.

 

[B.C.]

If it is 80 outside it will be tough without completely sealing the room and using an efficient a/c.

You could then use the fan to to cool the lights with sealed air cooled hoods.
If your basement air is 70, that is your best bet without a/c

I agree, sealing it up and ac is the way to go when it gets warm outside. But the first thing I'd do is run air through the lights though. That will help alot! Also, if ya can, have the ballast in another room, if you don't already. Good luck! BC

 

[B.C.]

Whoops I'm too slow. lol I see yer running without hoods. Maybe have a fan blow directly across the bulbs from one side to the other, and out the window? Instead of a fan blowing straight up. It may help suck it out before it has a chance to mix with the rest of the room. BC

 

[FreezerBoy]

I see all kinds of talk about exhaust and fans but, not a single mention of intakes.

 

[dongle69]

Did you miss the first post?

 

[FreezerBoy]

As a matter of fact, no. He says he's drawing air but he doesn't say through what. A crack under the door? A keyhole? What? You'd be surprised by how many here believe four 1" holes equal one 4" hole.

 

[smokinshogun]

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[baddru]

My intake is passive both when coming in from the basement and when coming in from the veg. My exhaust is a 6 inch output, and the passive intake from the veg room is also a 6 inch but still creates slight negative pressure. The intake from the basement air is in fact from under the door, however I figured the area of a 6 inch circle (pie r squared) and cut the door short enough to allow 20 square inches of open area for freash air to come in. I have also tried just leaving the flowering room door open during lights on in order to allow as much freash air as possible into the room.

As for the box restricting air into the AC, the bos is 4 feet long by 2 by 2. There is plenty of space around the back of the AC for fresh air, and like I said, the window that the box encloses is open. Is it possible tat the blinds are restircting air flow? The are just typical plastic horizontal blinds. Also it seems that if not enough air flow to the AC was the problem that the AC would work for a while until there wasn;t enough fresh air at the back to cool the condenser anymore.

I don;t care whether sealed or not. I know it wouldn;t be truly sealed one way or another as I have no CO2 and so would still need to turn the exhaust on every hour or 2 to bring in freash air that would then need to be cool by the AC again. This would be my preffered option as this way there is not a loud fan running all the time, only for 15 mins every hour or 2. But the AC really doesn;t seem to do anything?

 

[smokinshogun]

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[Diamonddss]

i had major temp issues until i cut off my exhaust because it wasnt on a tmer so it was sucking out the cool air before it could even get cool

 

[thekingofNY]

You said you have passive intake, but never went into details about it. How big is the hole? Reason i ask is my room is not 200% sealed, i also use passive intake, but before a few weeks ago i believed there was enough "holes" for air to pass thru, however now i leave the door (poly zipper) about 10" open at the bottom, for the air. Its still negative pressure in there and I managed to get my temps down to 84 (from the low 90s). When I add the A/C it should get down into the 70's.

edit: never mind i didnt see you answered that.... is it possible you are just venting all the cooler air you're a/c is making right outside?