Lookng for a More Effective Way to Vent and Cool????

so let me lay out the room then we'll get to the problem. the room is a 12x7 and 7 foot tall, with 3-1000's 2 are in 8" cooltubes and the other is in a 6" radiant air cooled reflector, all are in a row with a cap HO fan pushing outsid air thru them. The lights seam to stay pretty cool, I mean i can touch the glass and it just warm not to hot at all. I also have a 150 can fan filter with 8" fan which is set on a speed controler at about 80% running constant for good fresh air flow. which comes from 2 passive 6" intakes. To take care of the cooling i have a 5000 btu window ac hooked to a cap day night timer @ 80* day and 72* night. OK so heres the problem the fucking ac wont stop running. All the cool air is being sucked out by the filter. and having the AC run is heating up the garage where the intakes both draw from. I know this problem is going to get worse as summer comes anyone have ideas how i can fix it. venting fromor to the outside is not an option. Blah blah blah i hope that gives you a picture what im working with, so help a mf'er out

do you even need the AC? if you are drawing cool air from the garage and turning over the air at a fast enough rate,the room should never get hot considering most of your heat is from the lights & that is being handled nicely.I would try running the room w/out AC.

Yeah i just was thinking the same thing, as i was loggin on. I'll have to give i a try for a day or two and see how the temps go. Also the AC is in the garage and raises the temp there some so with out I'd have cooler air coming in too. I have a 12000 btu portable AC but dont really want to have to run that much power just for AC. any other ideas, HELP......

any other idea's ???

cut way back on the airflow through the room.if the AC has a switch to take in fresh air,that alone should give you enough fresh air for the plants.
or put your fan on a timer,5 min on every hour or 3 should be plenty.

why would i want to limit the fresh air to the plants they need all the air/co2 they can get??

it seems right now if i run the exhaust at full speed it'll stay under 80* but when summer comes and outside temps go from 50 to 80 its gonna get hot quick. thats when I'll have to figure out how to keepit cool with out running AC non stop. Or maybe I'll just add co2 and close up the intakes?????

Probably the best solution would be to add Co2. As you have figured out, you're exhausting conditioned air into the space where you draw your fresh air and that air is heated by the AC unit. VERY inefficient.
First, never exhaust conditioned air. Big waste of $$$. Second, never inject very hot fresh air. When summer comes you're gonna be in trouble.
Try sealing the room + Co2 injection and you can eliminate the superhot intake air completely. Make sure the airflow circuit for the lights never encounters room air. Straight in- straight out. Put the filter over in the corner with the fan on top and simply recirculate/scrub the air. The small AC should keep it plenty cool in there. 20 gallon Co2 tanks with regulators are pretty cheap.
I switched to sealed rooms about 8 years ago and will never go back. Much less headaches from worrying about getting enough fresh air, yields went up considerably and haven't had bugs in years. Try it, it's easier than you think.
Fred

Fred is spot on here.

Fred is right co2 is the way to go, however maybe look into getting a co2 generator instead of the tanks. The tank and reg will run you almost 400. And have to be refilled every week at the tune of $20 a fill up. Propane is cheap and in the long run a generator is more cost effective than filling up tanks every week, plus the time it takes to go to a air/gas store. The only downside of the generators is the heat.

mrduke said:

I also have a 150 can fan filter with 8" fan which is set on a speed controler at about 80% running constant for good fresh air flow. which comes from 2 passive 6" intakes.

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According to the manufacturer, the Can 150 has a recommended minimum fan size of 10" with a recommended min. air flow of 630 CFM. Are you getting good airflow from the filtered exhaust? It seems so as you are saying the cold air from the AC is being exhausted.

I remember once when I had the CAP thermostat in heating mode controlling an AC unit. A high differential on the thermostat can cause that as well. My CAP Dne has 3, 5, and 7 degree settings. At 7 degrees, the temp would have to fall 7 degrees below the setpoint before it turned off. That could be really hard with 3 1000s, even with air cooling, depending upon the intake temperature. I like to use thermostats with 1 degree differentials for AC.

I also couldn't tell if your temps were above 80 or constant AC was holding them at 80.

Can the filtered exhaust handle the cooling without the AC?

freds right, im going through the same thing right now.

you gotta seal the room and add co2.

just pull outside air through the lights and back outside.

It gets very hot where I live so I run a sealed room with co2 also. Besides dealing with extra ventilation it allows you to run your room up to 85 degres with the co2 so you won't have to cool as much. I still try to run between 80-84 tops but that's still warmer than non co2

thanks for all the info and constructive ideas. At the moment i have the ac set at 82* with a +-3 degree switch on /off. and the exhaust on full speed. The ac hasn't been on since i retuned it like this. But i know when it starts to get warmin summer I'll be screwed.

Fred you seem to know somthing about co2. everyone I've every talked with has so many different stories of how long to run and how long tanks last. Can you lead me in the right dirrection here? my room is 7x12x7= 588 cubic feet. also can i get away w/o a controllor/monitor and just run a regulator on a timer?? how would i know how long ? hope someone can help

mrmadcow said:

cut way back on the airflow through the room.if the AC has a switch to take in fresh air,that alone should give you enough fresh air for the plants.
or put your fan on a timer,5 min on every hour or 3 should be plenty.

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I would want to agree here with madcow
giving your data
the volume of your room is 588 cubic ft and your fan is at 150cfm It takes your fan 3.9 minutes to replace the air mass (assuming no loss) running your fan at 80% is empting the air mass in 3.1 minutes drawing in the warmer fresh air.
running your fan at 6.5% will cycle the room in 1 hour. 3 ways to look at it here. not in any order. Add C02 and dont vent the space except maybe 1 time an hour or 2. AC will still run but your room can run hotter. Find a way which to cool the intake air space (I think I saw this is what you are looking into right now) Or the last which is what I said first which I think might help either way. Which is to run the fan as low as you can and then fine tune up or down with the ac to find a happy medium. You can do the costs on running each way to find the most cost effective solution that best fits your situation.

flamdrags, you misunderstood its a can 150 filter with a 8" 725 cfm fan as exhaust.

does anyone have any links to a good co2 setup for dummy's??? I'm really starting to think i may have to go sealed in summer time.

You definitely will need to seal the room in summer. Even though the garage is insulated, they get incredibly hot in the summer due to no insulation on the door.
I've never tried to run Co2 without a controller. I suppose you could run it with a timer. Open the valve and use a tester to see how long it takes to reach 1500 ppm. Wait 20 mins and do it again. This second time would be your set point. Doesn't seem very accurate and changes in the environment, as simple as opening the door, will change the balance. With a minimal amount of searching the net, you should be able to find a controller for about $250.
As to tanks, can't help there either. I use large generators. But a few pointers might help. Buy two of the larger tanks. This will let you spread your refills to a couple of different locations. It also reduces how often you fill up. Most restaurant supply or carbonated beverage suppliers will have Co2. Welding supply houses also have it, but I've heard it's not as clean and can clog regulators. That's an unsubstantiated rumor on my part though.
Like everything else in growing, the start up costs are high. In this case, the Co2 cost is definitely justified by the increase in yield and it cures your heat problem.
Fred

right on thanks for the help fred. I think I'm going to get a tankless water heater AKA water cooled co2 maker, and a sentinel cppm-4. should take care of me

My room is 560 sq ft and I let mine run for 6 mins at 3 cu ft hr. Once an hour. You could use that or alter it now that you know what mines sey at with my controller. But you eant to be at 1500 ppm and ambient is 300 so you would do

580 x .0012 = cu ft to bring your room to 1500 ppm.

I go by 1/3 usage of co2 an hour so 3 hrs its all gone but if you vent every hour or two and start back at 300 ppm you can get more accurate.