The c02 question that never gets answered correctly

Hello,

Although I have been a satisified viewer and searcher of this site for about a year, this is my first post.

I have a question that I have been searching for an answer for for a while now, with no luck. Even my local hydro shop was unable to step up to the plate, so I now propose it to you guys:

I am running a dual room, liquid-cooled light setup with a liquid-cooled c02 generator and I am trying to figure out how to cool the room without expelling the c02.

The rooms are completely sealed (as best I could, and I am currently running a portable a/c that isn't cutting the mustard, so my question is this:

HOW DO I COOL MY ROOM WITHOUT LOSING C02???

Even though I am running liquid-cooled everything, I still build up heat from radiation, pumps for aero, and a nutrient chiller (1/10hp). Especially in the coming summer months.

Each time the c02 is pumped out by the a/c, the generator kicks in and and also pumps in more heat. I am running a computer-based monitoring /controlling system (growtronix), so I have the potential for optimum efficiency (Carnot is the goal for all you eggheads out there!)



Just so this thread doesn't get tainted with bad info:

• +Please don't tell me that window mount units wont pump out the inside air.
• +Please don't ask me questions about my setup not regarding my question-I will be more than willing to answer any PM's for side talk.
• + Please don't tell me to put a fan behind a radiator, as my cooling resevoir is a pool outside and in the summer will get to warm for this.

Thanks for any help!

Do you use any oscilating fans in your rooms? Keeping the air moving cools it and strengthens the plants. I keep one in my grow box and it works great for it.

Mr. Homegrown said:

Do you use any oscilating fans in your rooms? Keeping the air moving cools it and strengthens the plants. I keep one in my grow box and it works great for it.

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Thanks for the quick reply, but I have to correct:

Adding a fan does not cool. It make's it feel cooler because more of environment can interact more effectively by forced convection, and you get a more uniform heat distribution, but the motor in the fan actually adds heat to the sealed room.

My problem is actually removing heat energy from the room.

I don't mean to come off like an ass, I am just burdened by the knowledge of an engineering backround.

I was actually thinking of you when I was writing this question, as I have seen your sig on so many threads, and you have been pretty damn helpfull to others!

BUT, to answer your question, yes I do have oscillating fans, but in a sealed environment, they can only do so much.

You have been around, have you seen any tricked-out room that manages to cool while being sealed?

Thanks again for your quick reply!

I am having the same issue i keep my room gets to about 92 Im lucky to have a strain that tolerates such heat. Just don't make the same mistake i did I bought a portable AC unit to go inside my sealed room and vented to the attic room stayed cool but guess where my co2 went. I am looking for help on this also.

Listen dont get pissed, but you said you have an engineering background... Basicly you need to make your room into a refrigerator.. They extract the heat , without removing the air, you need and compressor.. Somehow...

Hope this helps.. maybe?

you need a wall/window a/c and thats that my friend, i had a portable a/c unit and the exhaust from that is whats doing you no good, your only bet is to exhaust that hot air and yes take a loss in co2, i run 3600 watts in air cooled hood attatched to a carbon filter, so i will have to constantly run my co2 tank more often as it is always getting sucked out, my opinion is you should vent(my filter/exhaust is on during light period) and run the co2 more often

Why not some sort of fancoil unit where the heat transfer is through a heat exchanger.


Whoops...sorry. I didn't notice the "fan behind the radiator" comment.

I have the same issue. I have yet to get a reply to the same problem. I'm with ya on this.

so let me get this straight, you designed and built your room without any exhaust? if you didnt want to make holes in the wall or some other reason then you shouldnt be growing in that space, my setup is built around the exhaust system and i run a carbon filter attatched to a "Y" with 2 450cfm fans, this cleans the air, cools the hoods and keep humidity in check, so what i lose co2, it costs me 18 bucks to fill a 20lb tank that lasts me a month, i think you may have made a mistake in getting all this high tech stuff without having a proper ventilation system

a bunch of you guys have completly sealed rooms, what do you guys do about odor? in many instances an a/c unit is not feasable, there for you need to suck out the hot air, i wouldnt set up a 3x3 closet unless i knew i could hook up duct fans

OK....here's the answer. Search Google for " Mr Slim". It is a small split system a/c where the evaporator is usually wall mounted and the condenser is remotely located.

Do you think your goal is reasonable? There is no way to cool the room without losing some CO2, but the goal should be to maximize the CO2 that you do have. If you inject CO2 right after your A/C runs a cycle, you will maximize the CO2 time. When the temp gets high enough again for the A/C to run, then you will probably need another injection/burn in order to replace that which was used by the plants anyway. You might just need to adjust the temperature hysteresis. Have you timed how long it takes for the room to gain a set number of degrees? For example, cool the room with A/C until it is 77°F. Burn the generator until you get 1500ppm. If you do that, how long until the temp hits 85°F? That's the amount of time you have for the CO2 to saturate and get used. Unless the temp raises extremely rapid, you will probably need to add more CO2 due to plants using it up anyway, so just run the A/C again then inject, starting the cycle over again.

The only other thing that might help is to use CO2 cylinders instead of a generator.

Have you seen this? http://refriginator.com/

slappy13 said:

Thanks for the quick reply, but I have to correct:

Adding a fan does not cool. It make's it feel cooler because more of environment can interact more effectively by forced convection, and you get a more uniform heat distribution, but the motor in the fan actually adds heat to the sealed room.

My problem is actually removing heat energy from the room.

I don't mean to come off like an ass, I am just burdened by the knowledge of an engineering backround.

I was actually thinking of you when I was writing this question, as I have seen your sig on so many threads, and you have been pretty damn helpfull to others!

BUT, to answer your question, yes I do have oscillating fans, but in a sealed environment, they can only do so much.

You have been around, have you seen any tricked-out room that manages to cool while being sealed?

Thanks again for your quick reply!

Click to expand...

Funny you ask, quite the oppoasite though. I read a thread where they reused the heat from the lamps to heat the room. Off subject but kind of ironic.

Anyway I had the same problem too. My only solution was to buy a climate controller to exchange the air in my box. When the room/ box hits the programmed temp I have an intake & exhaust fans that kick on. The controller shuts down the Co2 while the fans run.

Yes I lose the Co2 in the box but it works and I believe it good for them to get a fresh exchange. The oscilating fan is on the Co2 plug so it shuts down also, then kicks right back on to move the new cold air. It's been working for me and makes it so the fans don't run that often. Seems to take longer to get the box back to temp again. I'm no engineer but that's my results in stoner laws lol.

Maybe make a swamp cooler of some sort that goes back into the room. That layer of water would cool the warm air as you shoot it over it, It really would depend on your RH in the room, Just a thought. . . .

Also don't forget that CO2 is heavier than air. Try to get your a/c to extract your hot air from as high up as you can after letting the CO2 settle a bit (circulating fans off) and you will lose less that way.

mind phuk is dead on, this is the method i use in a smaller setup where i periodically vent warm air and odor, where my filter is seperated from my air cooled hood, i set the co2 to shut off when the vent fan comes on

Dirtydow420:

Basicly you need to make your room into a refrigerator.. They extract the heat , without removing the air, you need and compressor.. Somehow...

Click to expand...

Dirtydog420, I think your on to something!


morrisgreenberg:

you need a wall/window a/c and thats that my friend,

a bunch of you guys have completly sealed rooms, what do you guys do about odor? in many instances an a/c unit is not feasable, there for you need to suck out the hot air, i wouldnt set up a 3x3 closet unless i knew i could hook up duct fans

so let me get this straight, you designed and built your room without any exhaust? if you didnt want to make holes in the wall or some other reason then you shouldnt be growing in that space, my setup is built around the exhaust system

Click to expand...

morrisgreenberg,
-You need to more reading and less typing. A window mount unit will not work. It is the same as a portable.
-Do not dirty this thread with your odor issues. Not the place for it
-I built in an exhaust, but it is just that: EXHAUST. It defeats the purpose of having a truly sealed room by running it frequesntly. Its purpose is to bring in fresh oxygen and deplete methane build-up from the generator and that's it. Not a heat suck.
-Designing your system around your exhaust was a mistake, you should design your solutions to your problems, not the other way around.


gohydro:

OK....here's the answer. Search Google for " Mr Slim". It is a small split system a/c where the evaporator is usually wall mounted and the condenser is remotely located.

Click to expand...

gohydro, Oh my god I love you. I will contact them tomarrow.


mindphuk:

Have you seen this? http://refriginator.com/

Click to expand...

mindphuk, I have not seen that. Interesting idea, but my space is a bit bigger: 2 rooms. I wonder what there output is from one fridge? gram/watt?


Maybetomarrow:

Maybe make a swamp cooler of some sort that goes back into the room. That layer of water would cool the warm air as you shoot it over it, It really would depend on your RH in the room, Just a thought. . .

Click to expand...

Maybetomarrow, This option was considered, but the humidity output from those units is just crazy. I can't imagine how bad it would be with the aero setup I have got installed


mindphuk:

Also don't forget that CO2 is heavier than air. Try to get your a/c to extract your hot air from as high up as you can after letting the CO2 settle a bit (circulating fans off) and you will lose less that way.

Click to expand...

mindphuk, CHECK! I currently have the a/c mounted as high as possible


Thanks for your guys help so far, its great to have a collective knowledge! For all those in my same boat, we'll sail to cool territory soon! I think MrSlim is our answer, so long as he is not a noisy bastard.

you can do a number of things..

if you want to lose co2, you can run a controller, and just pump more co2 into the air, but by you having a generator, you are adding more and more heat, so you will have to run the ac more often, and will be extremely inefficient as you already know

you can also run a mini split ac, which will just pump cold air into the room, without exhausting any, but will result in a positive pressure in the room, which will in turn push some of the co2 out..

another option would be to look at something like the ice box from hydro innovations.. its basically a small radiator that attaches to your hood, which you run cold water through, and if you keep the water cold enough, would make the exhausting air colder than the air in the room, effectively turning it into an a/c.. the only problem with this setup is you would need a pretty hefty chiller, as well as the icebox units, which would mean a lot of money up front, but in turn it would be cheaper to run electricity wise, than the a/c, and you would run the generator less, saving on co2, and not needing to cool as much..

Co2 is really only effective when ALL conditions are optimal. From the sounds of your set up I'm not sure the conditions are optimal. Turn your lights off for a few hours, run the a/c, let it cool then run the Co2 along with Mr. Slim.