CO2 in a closed system, need some wisdom

[KushmasterJ]

Alright so i'm starting up a pretty small grow op in a closet of mine using some equipment i had left over from another project. I have an air-cooled reflector for my light, im running a carbon filter on the intake side of the reflector with a vortex fan pulling everything out of the other end of the reflector and through some ducting that was previously used to exhaust my last setup. i still have the option to exhaust the air from the room, however i'm interested in supplementing my system with C02. So what i was wondering is, if i have a CO2 tank running with a monitor and controller, would it be fine to just exhaust the air that goes through the carbon filter and light reflector right back into the same room? that way the CO2 remains circulating in my enclosed setup...the light would still be cooled and the air would still be filtered...temperature really isn't a concern, i have an a/c and having C02 will allow me to run hotter temps anyway.
are their any dangers or downfalls to this concept? i greatly appreciate any input or advice anyone has about this situation.-thanks!

 

[TURKEYNECK]

the only downfall I see would be heat..

 

[Puffin Afatty]

when I sealed a room, the plants didnt grow as well as when I allowed a fresh air intake and heated air exhaust :hubba:

:farm: now, I just provide co2 constant with the intake, works great :aok:

 

[The Hemp Goddess]

I don't understand the purpose of a carbon filter on an air cooled light?

I do not think that you are going to be able to keep the room cool without an exhaust. When you exhaust the light reflector into the grow room, it is rather like having a heat duct in there--the air is very warm. If you have air coming in, you have to have air going out...

 

[Killertea08]

You need to exhaust your room with a separate fan connected to your closet. Have a dedicated fan for your lamp and a fan for exhausting your room. This way the heat from your lamp goes right out of the room and the heat from your room goes right out. I understand your reason by combining the two to save electricity, but you will be pulling SUPER HEATED air coming out the other end of your lamp. The ONLY purpose of the air cooled lamp is to pull cooler air from outside your grow area through your lamp and outside your grow area. You should only be exhausting your space through your carbon filter not to combine the two.

 

[Tater]

I'll comment on this when I get home been doing a lot of research peace.

 

[Tater]

Ok here we go. The best way to do what you are trying to accomplish would be to pull air from outside the room through your hoods and back out of the room. This will cool your lights much more efficiently. If you just recycle the air the room will get way to hot and your ac will be running all the time. Also this allows you to control the PPM of your CO2, which you want around 1500 ppm while the lights are on. You also need to maintain temps in the 80's during lights on. When the lights go off you need to exhaust the CO2 and drop the ppms down to 800 or so. It is very possible to set up a totally self contained room and is actually the recommended growing method of the guys at Advanced Nutrients.

Killertea08 you don't need seperate fans it all just depends on your setup. For example I use a UV ozone generator which removes all the smell from my room, then I have a inline fan hooked up to two hoods which both pull air from the room through the hoods and vents the heat into my hvac system heating my house in the process. With passive air intake from my attic with ambient temps at 20C I maintain a temperature of 25C in my room. With active air intake from my attic (meaning I turned on the fan that feeds the room with fresh air, one day I'll hook it up to a thermostat) I can hit ambient no problem.

PS to anyone out there if you are going to vent the heat into your HVAC system you might need to take humidity into account unless you live in a dry cold area like I do for 8 months of the year and then the humidity added by my garden is a welcome addition to my house.

 

[KushmasterJ]

I don't understand the purpose of a carbon filter on an air cooled light?

My first setup involved the sea of green technique and a hydrohut. The hydrohut is pretty much airtight and light proof when the few duct size holes are covered with velcroe secured flaps. Lets say all the flaps are closed except for one on the cieling, and that one open hole has a vortex fan pulling air out of it, but the air had to first travel through a carbon filter and my air cooled reflector, any odor in that room would be eliminated by the filter before it went through my light and out of the cieling of the hut. The result is an air tight hut that has the "walls" being sucked inward because the fan is pulling that air out.
Now lets say this hut is sitting in a nice a/c cooled bedroom, and lets say we remove the velcroe flap that is covering a ducting hole at the bottom of the hut and replace it with some nylon panties as a filter.
All that fresh a/c cooled air in the bedroom is then sucked into the hut, through my filter and light, and back out of the hut into the bedroom, allowing for constant circulation...
It worked great but CO2 would have helped the yields alot, and using that same concept would result in any CO2 i supplement the growspace with to be sucked right out by that powerful vortex fan before the plants even get to say hello, now i dont know how fast plants can take CO2 in but i would think it has to stick around for a while...

killertea08's advice on cooling the light from outside of the growspace makes ALOT of sense, however that still still leaves the issue of exhausting the CO2 right out the room with the seperate dedicated exhaust fan. I guess that having my light cooled with a/c cooled air from outside of the closet would allow me to turn off a dedicated exhaust fan for certain periods of time to feed the babies the CO2 without worrying about massive heat buildup from the light.
but then that leaves me having to figure out what kind of CO2 feeding schedule id have to use, id really prefer to have it there during the entire time the lights are on.
maybe eliminate the dedicated exhaust and prevent heat buildup with fans? there wouldnt be a constant supply of external fresh air but there would be plenty of circulation inside the room from the fans and there would also be plenty of carbon dioxide :]

im just not sure what would be best....

 

[Killertea08]

Tater

Killertea08 you don't need seperate fans it all just depends on your setup. For example I use a UV ozone generator which removes all the smell from my room, then I have a inline fan hooked up to two hoods which both pull air from the room through the hoods and vents the heat into my hvac system heating my house in the process. With passive air intake from my attic with ambient temps at 20C I maintain a temperature of 25C in my room. With active air intake from my attic (meaning I turned on the fan that feeds the room with fresh air, one day I'll hook it up to a thermostat) I can hit ambient no problem.

I can see that your idea works. But to the novice grower the way I explained is way easier to do. HVAC? What if you dont have HVAC are you just going to chop up your ducting in your house to heat it? Sounds easy to do right. I dont think so.

Tater

The best way to do what you are trying to accomplish would be to pull air from outside the room through your hoods and back out of the room.

I think I said to do this but if you want to use one BIG inline fan to exhaust your lamp and exhaust your grow space all at one time is a good idea so save electricity but make sure to vent this SUPER HEATED air somewhere other then your grow room or your a/c will have to work overtime for the added hot air. Yes Tater you could run this to your ducting to heat your house but if its hot already then you will have to exhaust it outside or in your attic somewhere else but through a carbon filter/ ozone.

I just think my idea sounds easier to do one fan for lamp one fan for exhaust.

 

[KushmasterJ]

Tater you pretty much explained it perfectly.
i made my post while you were posting yours so it showed up after you provided the solution :/
ill just clean the air inside the room with some sort of purifier... like maybe my carbon filter just chillin with a vortex on top hahaha... think that would that provide enough odor control?
anyway,thanks alot!

 

[Killertea08]

KushmasterJ you are going to need to add an intake source so when you exhaust your space you dont build up a vaccum like you said the walls would all move in. your supplementing your room with co2 and thats good but if you have an intake source to bring in the fresh air this will help with the temps too. The best way to do it and not loose co2 out the vent is to by a damper valve. Its a 4in spring loaded one way valve. when you exhaust your room and a vacuum builds up the valve springs open when the fan shuts off it springs back. You may need to have a/c in your grow space to cool it off and not rely solely on your fans. This way you dont loose your co2 in the room. Buy a portable a/c and have your fans exhaust on a timer to turn on at your pre selected time every hr or two to exhaust co2 depleted air.

 

[Killertea08]

If you have a/c in your grow room to keep temps at 80 then you only need to exhaust every so often to pull out co2 depleted air. At that time your co2 shuts off and then turns back on when your fan shuts off. Make sure your co2 controller has a photo sensor to shut of co2 during dark periods.

 

[Tater]

Killertea08 he is running CO2 no ventilation of the grow space is needed if you keep temps within range by pulling fresh air through the hood. And what are you talking about chopping up vent systems and hvac I was simply providing an example. Venting into your HVAC is a simple solution for novice growers but not the only one. You can vent out your roof or into your sewer. Venting into your attic as you mention is a really bad idea. What happens is because of the temperature differences between your attic and you grow room condensation will form and collect which will then in turn cause mold which will later cause whats known as sick house syndrom. So thats a bad idea.

I just think my idea sounds easier to do one fan for lamp one fan for exhaust.

Thats your opinion and you are entitled to it but the fact is an exhaust fan is unnecessary in a CO2 setup and is actually detrimental. I think you may be confused about growing with sealed rooms and CO2. I also understand that you had already told him to pull air from outside the room through the hoods and back out again I was simply expanding on the idea and trying to explain what his goals should be if he is trying to run CO2 and have it be of benefit.

KushmasterJ Glad the post helped, shoot me a line if you got any more questions about how to set up CO2 in your grow hut.

 

[godspeedsuckah]

when I sealed a room, the plants didnt grow as well as when I allowed a fresh air intake and heated air exhaust :hubba:

:farm: now, I just provide co2 constant with the intake, works great :aok:

how exactly do you provide the constant co2 Puffin?

 

[The Hemp Goddess]

My first setup involved the sea of green technique and a hydrohut. The hydrohut is pretty much airtight and light proof when the few duct size holes are covered with velcroe secured flaps. Lets say all the flaps are closed except for one on the cieling, and that one open hole has a vortex fan pulling air out of it, but the air had to first travel through a carbon filter and my air cooled reflector, any odor in that room would be eliminated by the filter before it went through my light and out of the cieling of the hut. The result is an air tight hut that has the "walls" being sucked inward because the fan is pulling that air out.
Now lets say this hut is sitting in a nice a/c cooled bedroom, and lets say we remove the velcroe flap that is covering a ducting hole at the bottom of the hut and replace it with some nylon panties as a filter.
All that fresh a/c cooled air in the bedroom is then sucked into the hut, through my filter and light, and back out of the hut into the bedroom, allowing for constant circulation...
It worked great but CO2 would have helped the yields alot, and using that same concept would result in any CO2 i supplement the growspace with to be sucked right out by that powerful vortex fan before the plants even get to say hello, now i dont know how fast plants can take CO2 in but i would think it has to stick around for a while...

killertea08's advice on cooling the light from outside of the growspace makes ALOT of sense, however that still still leaves the issue of exhausting the CO2 right out the room with the seperate dedicated exhaust fan. I guess that having my light cooled with a/c cooled air from outside of the closet would allow me to turn off a dedicated exhaust fan for certain periods of time to feed the babies the CO2 without worrying about massive heat buildup from the light.
but then that leaves me having to figure out what kind of CO2 feeding schedule id have to use, id really prefer to have it there during the entire time the lights are on.
maybe eliminate the dedicated exhaust and prevent heat buildup with fans? there wouldnt be a constant supply of external fresh air but there would be plenty of circulation inside the room from the fans and there would also be plenty of carbon dioxide :]

im just not sure what would be best....

IMHO, the addition of CO2 is overrated and complicates the ventilation/cooling of your space, especially with a very small grow. If you are exchanging the air in your room often enough, your plants are getting enough CO2. You cannot prevent heat buildup with fans. I cannot imagine any way to keep your space cool without exhausting air out. I'm sorry, but I just don't see this plan as being workable. I have a room 3 x 6.5 x 7.5. I run a 1000W HPS. I use a vortex fan and ducting to cool my light. Cold air is pulled from a cooled room (or outside if it is winter), through the light and out through the ceiling into the attic. I have another fan that pulls cool air from the crawl space of my home. I have another passive intake from the crawl space. I have a large exhaust fan mounted near the ceiling. Air is exhausted out through the ceiling into the attic. I have an oscillating fan that runs when the lights are on. This is what it takes to keep the temp under 85F.

 

[andy52]

my set up might not be right but it works so far.i have a 430 cfm blower,pulling thru a carbon filter,thru the reflector and out the top,into my basement.i have anothe blower,in-line duct,bringing air from my portable ac unit,into the tent.with an oscillating fan running 24-7. would it be easier to use the ac to run thru the reflector?to date i am keeping my temps at about 72-73 degrees.

 

[Tater]

Hempgoddess be careful about venting into your attic you will end up with mold, take it from someone who has been in the roofing/siding/home repair business for over 13 years. Poke your head into your attic, if you see little tiny black dots on the underside of the OSB or plywood then you already have black mold. This is a serious issue and can lead to health problems and if it is ignored long enough it can even lead to death. Just something to think about. You should install a roofjack and vent directly outside. A roofjack takes less than 5 minutes to install and can be bought at any hardware store, most guys will even show you how to install it. CO2 is not overrated it just isn't commonly done properly and therefor most people that try it do not see the benefits. Like I said before if you cool your lights well enough you do not need to ventilate your grow space.

 

[KushmasterJ]

Once again thanks a lot for all the input. I just finished setting up the closet and I'm running with temps at 82 degrees with the light on during actual daylight, ill be putting the light on at night so hopefully it'll be even lower than that. With my 600 watt HPS I'm happy to be running about 9000 lumens per sq. foot with almost no heat buildup. Cooling the lamp with that A/C air from outside the closet really helped a lot. I also went out and bought a second vortex fan, this one i use directly on my carbon filter which sits right between my two pots pointed directly up at my reflector... this really helped a lot with the heat as well, not to mention great air distribution throughout the small sealed closet(soon my CO2 hose will be sitting right above the fan so that the precious gas is distributed evenly)...the filter will also take care of the odor.
Tater was absolutely correct in stating that ventilation is not necessary when the light is cooled properly...
Not that I would get the temps this high but I've read that supplementing C02 enables you have temps as high as 90 degrees.. I'm not backing this its just what I've read... if its true i still have quite a cushion.

That information about not venting into the attic came at just the right time since that is actually what I was doing haha... will fix it today.

Tommorow two fresh Dabney Blueberry Clones will be introduced to their new home. Ill be using the LST technique to maximize yield in my small space...
Thanks ALOT for the help, wish me luck!

 

[Tater]

Glad its all working out now lets see some pics !!!! All the best on your future grows.