1. We are currently experiencing issues with viewing and uploading images, our team is working on the issue.
    Dismiss Notice

Sealed room, window ac unit, co2 ???

Discussion in 'Grow Room Design & Setup' started by grindrx, Feb 17, 2009.


    grindrx Active Member

    Hello all,

    Have done extensive reading from this as well as other sites and have learned an ass load of awesome information...thanks.

    I have a couple of questions that I can't seem to find agreeing answers to.

    My question is regarding co2 levels in a sealed room..well almost sealed.

    A room that is entirely sealed except for the window ac unit as it needs exhaust to cool properly.

    Will co2 be needed, or will opening the door say twice a day and the exhaust be enough?

    Do these DIY co2 generators work ie yeast sugar mixtures effectively?

    Any input on this setup would be appreciated..

    Thank you.

    AeroKing Well-Known Member

    Your best option is to supplement the CO2 in the room. Window A/Cs exchange very little air if any. Any other method of replenishing CO2 will be counterproductive to the air conditioner.

    grindrx Active Member

    Thank you for your response, I was looking all over the internet for how much air was transferred from inside air to outside air, but could find any clear info. You saying "very little" makes me feel much better as I don't want to waste co2, or counter act the sealed room aspect.

    With that being said, now onto co2:
    This seems like a pretty new unit for the simple fact that I haven't found much in thread about it...any input or anyone that has used it?

    Room size: 12X7x5 so 420sqft...haha thats effin awesome! Anyway with this unit it from all the research I have done I think I would only need it to cut on at most for 5min an hour to keep room at around 1500ppm. Height is an issue at only 5ft so scrog with 4 plants along with 2 mums and 4 clones blocked for light reasons.

    Any input on co2 with this setup would be appreciated.

    Rudiger Well-Known Member

    I use a window a/c and my co2 ppm drops about 3-400 when the ac kicks on for 15-20 minutes.

    I was looking at the water cooled gen as well but when you include the price of a reservoir, and the space for it and a cooler if you only want to run a small res and a pump to flow water, the price gets up there. I ended up going with a 4 burner regular generator for a little cheaper. You can still vent out the heat on this kind, but with my room at 32 square feet or 256 cubic feet, my gen only runs for 1 minute to bring it up from 700-1500ppm.

    Just make sure you know your measurements before you get mixed up on something. If your including height in your room calculation then you talking cubic feet, not square feet. You only have 84 square feet.
    And if you do a search on here for that water cooled gen, there was a decent thread about it and some guys that use it. VonDankenstein uses one im pretty sure.

    BAYAREAMEDICAL Well-Known Member

    urbangrower.com he does nuthing but sealed rooms, i run co2 15 mins a day ina sealed room with my ac running 24hrs

    ugmjfarmer Well-Known Member

    A window AC is a great idea to cool a small room like yours. With 420 sq ft, you only need 1000btu for the actual space. calculate an additional 4000btu for every 1000w lamp and your set. Using the perfect garden on the see more buds DVD 3 video, you can see how they had two sets of AC, Dehumidifier and Window AC in each of the boxes. Perfect setup.

    As far as CO2 supplementation, using a burner means you will need to deal with the excess moisture that the burners will produce. In most small box grows, I have seen a dehumidifier with the burners. You can sometimes get away without the dehumidifier if you have tanked CO2. Tanked CO2 is also easy to use to kill spider mites as well as sterilize the room between grows. Im sure you could do that with burners as well, but tanked seems to work for something small.

    I am going to a CGE (closed growing environment) after my first harvest. A 10,000btu AC should work for me. I'm going to hang a burner, and put a dehumidifier below it. All of it controled by a climate gizmo w/ a PPM monitor. I'm doing a stadium (VSOG) with 2000w, and I might go hydroponic, but soil works great and is cheap. My space is 480sq ft. And the reason why I would go with the three of them combined is simply, getting the environment perfect makes for a great harvest.

    Be prepaired for an extra $20 a month to run this all though. Headsup.
    fat sam

    fat sam Well-Known Member

    yeah if your using an ac then sealed is the best way to go, if your using a co2 burner then you will need to vent 1-2 times a day just to be safe, the good thing about the ac is it will take care of your humidity issues to

    grindrx Active Member

    Opps I meant cubic feet...You only have to turn you ac on for 15 minutes...I have to leave mine on almost constant. Does this mean co2 supplement will be useless. Aeroking stated above with an ac unit that there is little if none air transfer from outside air to inside air, is this not true, or does co2 being pulled through the ac die as its cooled and pushed out?

    Rudiger, what type of burner are you using, does it connect to propane tank or do you have a gas line? If you use a tank, how often are you filling it? Room sealed or vented?

    grindrx Active Member

    Awesome video ugmjfarmer watched all of them..thanks

    Rudiger Well-Known Member

    I use aircooled lights with cold air from another non used room, and my lights come on at night, so its a colder than day time air. It keeps the lights pretty cool. I have a 4'x5'x6' veg room with a single aircooled light and the temps never go above 74. The ac never comes on in there, so I use bottled co2 for that one and the burner for the flowering room.
    They are both sealed rooms.
    I use a cvr burner on propane. I used a bottled co2 at first in the flowering room and it lasted 5 weeks, and switched to the burner and it lasted 5 weeks as well. $65 for a tank of co2 for versus $20 for a tank of propane. Just that initial big bill for the generator is a hurdle. It works out to be cheaper in about 16 months haha

    grindrx Active Member

    Awesome, I think you have changed my mind on going with the hydroGEN model. Just a couple more questions if you dont mind, you have been alot of help.

    This is the one I'm looking at now...I won't be able to afford a co2 meter for awhile so how do you keep the room at around 1500ppm, also this one only has 1 burner vs. 4 like yours, how do I understand how long to keep it on for each hour? Keeping in mind that my ac will most likely be running...

    grindrx Active Member

    Nevermind, I found this: http://www.hydrowholesale.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=hydro&Category_Code=co2

    Thanks for all the help!

    Rudiger Well-Known Member

    Yea that SeedsEct guy is pretty cheap. At first he was cool with shipping to Canada but he changed his mind I guess.
    You can get a rough way of doing it, through that calculator you have. Plants are gonna use more or less co2 at different stages as well. I mean bigger leafy plants are gonna need more than a seedling is gonna use.
    I would look into getting replacement burners for your gen if you get that one. I know you can get them with the CAPs. You have a pretty large space to fill, and one burner is gonna take a bit to get there. They must be pretty cheap, I'm sure I saw them before for $30 or something. Even if you only get one more, 2 is better than one in this situation.

    grindrx Active Member

    will do, thanks.

    grindrx Active Member


    This link above answered alot of questions about ac units in sealed room...also if trying to decide between portable ac vs. window ac, keep in mind that portable ac units will vent more air in then out of the room than a window ac unit will. So for a sealed room a window ac unit would be better fit. If this information is wrong please let me know, and why.

    AeroKing Well-Known Member

    They make "dual hose" portable A/Cs for this reason. They have an intake and an outtake to isolate the heat exchanger, much like how we air cool hoods in a co2 room. Sometimes they will need to be modified to really cut down the exchange.

    grindrx Active Member

    I looked at some portables, the ones I saw only had one vent. So ones with dual vents are better at sealing the room than a single vent? How do you modify it?

    AeroKing Well-Known Member

    Dual hose units can draw air from an exterior source, heat it and the push it into yet another area without exchanging air with the area they are in.

    Single hose units don't take air from another location, they take it from the room and blow it out the exhaust.

    With mine, even though there is an in and out hose for the heat exchanger, there is still a louvered vent to the room.
    To modify, this needs to be sealed (with foil tape) and in my situation, a longer run of duct than the unit is rated for requires a small booster fan to draw the heated air to the outlet.

    FLoJo Well-Known Member

    split ac units are the way to go in a grow room, they draw air from the box wherever you put it, condense and cool it without drawing out co2 from your room.. i have never seen one of those hydro gens, they look pretty neat.. seems like there is not a lot of info about them though. buyer beware
    AeroKing likes this.

    AeroKing Well-Known Member

    For sure, if you've got the $, go with the mini split A/C. They are perfect for this application. +rep

Share This Page