Co2 Generatos, does the Co2 exit from the top or bottom?

[HendrikOl]

Hi,

I would like to use a Co2 generator and attach small fans on the exit side which will blow the Co2 through ducting to my plants. I want to block off the ducting at the end. However the co2 will be escape through small holes which I will create on strategic places during the length of the ducting.

However I do not know if the Co2 should be sucked in from the bottom or the top of the Co2 generator? It might be a stupid question to ask but Co2 is heavier than air so it falls down. If taking this into account I would need to attach the ducting to the bottom end of the Co2 generator. Or is the Co2 exiting from the top and settles to the floor at a later time?

 

[TheyCallMeJJay]

I'm having a hard time understanding why you would want to do this. Respectfully questioning your judgement here. I've never heard of anyone doing this.

Can you explain why you want to do this?

Plants do not like massive amounts of C02
If it were me I would just keep the room at a certain level and forget the fans and ducting.

 

[queequeg152]

lol gasses do not stratify like that.

co2 will not fall, it will diffuse into the air. you will not be able to detect a measurable difference in co2 from top to bottom what so ever, absent some very very cold temperatures.

your co2 exhaust is probably a great deal warmer than the ambient conditions. pipe it in from the bottom if it makes you feel good.

 

[HendrikOl]

@ queequeg152: Co2 settles to the floor because it is heavier than air. So your theory that it stays diffused in the air is wrong.

@ TheyCallMeJJay: Co2 bottle users attach piping to their bottle and route this piping over their plants.

This piping is perforated with small holes and the co2 "rains" down to the plants.

So why wouldnt it make sense to use the same concept for my co2 generator?

 

[queequeg152]

@ queequeg152: Co2 settles to the floor because it is heavier than air. So your theory that it stays diffused in the air is wrong.

no it does not.

lol there is more ARGON in the air than co2. why are we not suffocating every time we venture to the beach? why is there helium gas at 0 elevation?

its all so much more complicated than x weights more than y so x is on the bottom.

 

[TrichCrazy5280]

Hi,

I would like to use a Co2 generator and attach small fans on the exit side which will blow the Co2 through ducting to my plants. I want to block off the ducting at the end. However the co2 will be escape through small holes which I will create on strategic places during the length of the ducting.

However I do not know if the Co2 should be sucked in from the bottom or the top of the Co2 generator? It might be a stupid question to ask but Co2 is heavier than air so it falls down. If taking this into account I would need to attach the ducting to the bottom end of the Co2 generator. Or is the Co2 exiting from the top and settles to the floor at a later time?

Be careful when doing this. This actual exhaust off the burner is extra hot and humid. You dont want to be pulling that directly onto your plants, it can cook them. In the past i have placed wall mount fans to closely to my burner and the fan pulled the hot, humid air directly on the plants. It cooked them and saw adverse effects. Be careful. Proper room ventilation should be enough to keep it mixing.

 

[TrichCrazy5280]

Sorry, proper air circulation, not ventilation.

 

[Mikell]

Concentrated CO2 disperses in the air poorly, especially in a shoddily designed grow room. A large percentage of grow rooms fall in to this category.

Carbon Dioxide In Greenhouses

Scroll down to "Distribution of Carbon Dioxide in the Greenhouse". This is just an example from current reading material, I also highly recommend the link for anyone using or planning to use CO2. Even in open air environments, without adequate air flow (wind), a C4 crop like corn can greatly reduce CO2 levels up to 6-8 feet above canopy. Yes, I realize cannabis is C3.

Source - for those scientifically minded fools. Not the original article I was looking for, but supports my last claim.

As others recommended, provide proper air circulation. A box fan or two pointed at the wall near the burner is more than sufficient to aid heat/CO2 distribution. Oscillators to break up the canopy, etc.

FWIW, if you don't have a solid (near professional level) handle on ducting, I would avoid fiddling with it as you have suggested. From my own experience and others, it's inferior to properly sized, vented ducting and can be downright counter productive with a cooling unit on one end.

 

[indocult]

Co2 does not fall or sink. This is a misconception started and stirred by mushroom forums.

If the air worked like that, we'd all be dead from the massive Co2 layer on the surface of the earth, or at least we'd be evolved to breath heavy Co2 rich air.

 

[Mikell]

CO2 mixed in to the air will not sink, but concentrated CO2 from an injector will. Temporarily at least, it will equalize throughout the area, but I still prefer to increase circulation around the source. I believe convection created by a burner would carry everything upward.

Without adequate circulation and a dense canopy, localized low/high spots are possible, to my understanding. It isn't uncommon to see an overpacked grow room with one fan on the wall. It wouldn't be too hard to test either way.

Air does kind of work that way, but I believe pressure and constant circulation of the atmosphere stops any minor settling. There are numbers tossed around of what the atmosphere would look like in a perfectly still world. Although it's impossible it would ever happen.

 

[theother]

Buy a gen meant to be ducted (almost none of them are, those that are usually are ducted to remove the heat and leave the co2, they use a heat sink that is supposed to be ducted out) modifying a normal square hanging propane or natural gas gen to be pulled into ducting is really just making an already dangerous thing even more dangerous. You really don't want something effecting the flame of the gen, you don't want fans hitting it or anything like that. Is this just to move the co2 throughout the room? Like the gen would be in the bloom room, then ducted to blow onto the plants? If so just use oscillating fans, they should work fine.

If you are talking about remote mounting it in another room and then ducting it into the bloom room, then I would say use a lung room.

CO2 mixed in to the air will not sink, but concentrated CO2 from an injector will. Temporarily at least, it will equalize throughout the area, but I still prefer to increase circulation around the source. I believe convection created by a burner would carry everything upward.

Without adequate circulation and a dense canopy, localized low/high spots are possible, to my understanding. It isn't uncommon to see an overpacked grow room with one fan on the wall. It wouldn't be too hard to test either way.

I think your right, the heat from a gen would definitely make it rise at least at first.

 

[queequeg152]

CO2 mixed in to the air will not sink, but concentrated CO2 from an injector will.

yes i have to agree with respect to COLD co2, from a bottle or dewer or perhaps dry ice. I welded for a few years in high school, and its made clear how the shielding gasses behave, and argon at least does indeed fall and pool over your work piece.

but it does not remain so. even if the air is PERFECTLY still, it will diffuse into the air. unless you have insanely cold temps, approaching their liquid temperatures they will not appreciably stratify over say... 8 or 10 feet, or however tall your ceiling is.

gasses of various weights WILL form gradiants, but over comparatively huge distances... 10's of km, and huge temperature differences.

co2 from combustion will diffuse even quicker. even the most efficient furnaces still have an exhaust gas like 10 f higher than ambient conditions.

this is all very easy to prove. you just need one of those IR co2 HVAC occupancy sensors.