CO2 generator location?

[Hookah79]

I've been contemplating on getting a couple of CO2 generators for my veg and flower rooms.Searched online for info with no luck.Both of the rooms are rectangular and have 7' ceilings.My ac duct runs in the center of my flower room all the way across.It also runs the same in my veg room except it has 2 rows of reflectors on one side ,and one row on the other.

I want to mount the generators on the back side of the room where the duct ends,i have about 4 feet clearance from the wall.But i am concerned ,would the CO2 be blocked by the ducting in front of it?Would it reach all the way across the other end of the room?Should i just get smaller generators and install em on the opposite side of each ,right where the reflectors start?(more labor intensive).

There's alot of air circulation in the rooms in case you were wondering...

 

[Floridian]

It doesn't really matter on which wall you mount it on,especially since you have good air circulation.What matters is you want to mount it as high on the wall as you can without it being a fire danger to your ceiling.I have run a cd-6 in my 8 by 8 room for quite a long time.I have it mounted high maybe 18 inches below the ceiling,the co2 is going to drop that's why you mount it up high.You would really have to mount it up there though like all the way up top before it would present any hazard.The flames are pretty well contained within the unit and I'm sure the newer ones are even better contained.I got my last greenair CD-6 about 7 years ago.Get a controller do not use a cyclestat which is much cheaper but the amount of co2 released is based on room size only.It doesn't take into account the number of plants plant size etc.The ducting 4 ft in front of the unit will make no difference at all

 

[Hookah79]

It doesn't really matter on which wall you mount it on,especially since you have good air circulation.What matters is you want to mount it as high on the wall as you can without it being a fire danger to your ceiling.I have run a cd-6 in my 8 by 8 room for quite a long time.I have it mounted high maybe 18 inches below the ceiling,the co2 is going to drop that's why you mount it up high.You would really have to mount it up there though like all the way up top before it would present any hazard.The flames are pretty well contained within the unit and I'm sure the newer ones are even better contained.I got my last greenair CD-6 about 7 years ago.Get a controller do not use a cyclestat which is much cheaper but the amount of co2 released is based on room size only.It doesn't take into account the number of plants plant size etc.The ducting 4 ft in front of the unit will make no difference at all

Kudos for the reply
I am aware of hangin it as high as possible with 18 " below the ceiling,thus my concern since my ceiling is low .My canopy sits at 5 feet high give or take.My ac duct is 5'8 from the floor.I am hoping i can get an even distribution all around.Btw i will be using a controller with the burner.

 

[Bobby Boucher]

I have 5' clearance in my tent, and the whole thing fills up to the top. Co2 can be generated below canopy level, you'll just need to use a couple floor fans facing upwards to bring it up off the ground.

 

[Mikell]

CO2

-does not "drop"
-does not hang about

Gases interact quickly, especially in a grow room. The draft alone would negate any unfounded statements of "dropping".

Don't point fans at burners.

 

[queequeg152]

lol why is this myth still around? yes, mikell is right... co2 does NOT DROP, stratify, or even measurably change with these microscopic changes in elevation.

will co2 concentration change over say... 10,000 feet? yes, but this is not just due to weight... but to a combination of factors, weight being a big one, but not the only one.

gases in the atmosphere are in solution at the standard temperatures and pressures that we live in.

do this experiment:

salt is heavier than water. add a gram of salt to a cup of water, mix well, and tell me if the bottom of the glass is saltier than the top. measure it with an ec meter if you like... you can extract solution from the bottom with a pipette if you have one.

then do this experiment.

move your co2 source to the floor, or to the ceiling. place your co2 sensor at the opposite location, and tell me if there is any measurable difference.

then do this thought experiment:

argon is heavier than oxygen by a large margin. our atmosphere is like 1%argon. co2 is like .04%

why do we not asphyxiate inside caves or inside buildings or inside other calm air enclosures?

why do we have to liquify and fractionate the atmosphere to obtain argon( industrially valuable gas)? why not build a massive isothermal enclosure and introduce laminar atmosphere from the top, allow the gasses to stratify, and select for ONLY the argon layer? you could produce argon at a fraction of the price!!! no need to liquify nitrogen, oxygen and co2, and seperate them all out in steps! cash MUNAY.

also you need to remember that you are basically using clean flue gas as your co2 source... this gas will be warm if not downright hot. even full condensing furnaces produce flue gases at like 80+ f.

warm air will RISE, not fall... your co2 will actually first rise into the room, then get tossed around by your hvac equipment.

 

[Bobby Boucher]

Well, god damn. If I had a nickel for every time I read that co2 falls. I'd buy whatever ^^ these two are selling, though. Smart cookies.

 

[queequeg152]

Don't point fans at burners.

this is actually a very good point i had not ever thought about.

these cheap co2 generators are basically Bunsen burners surrounded by a metal enclosure... there is no draft inducer, and there is no flue pipe protecting the flow of gas(for obivious reasons).

when you aim a fan at a co2 burner... you could possibly disrupt the natural convective current pulling the air up. some of the flue gas could then be re ingested by the burners intake, thus depriving the burners of the amount of oxygen that they were calibrated to consume.... and poor combustion can produce carbon monoxide and maby ethylene.

also, i imagine the possibility of this happening would increase radically if one were to put the burner very close to a ceiling regardless if a fan were pointed at it.

in the aerospace field they call this hot gas ingestion, and it can cause jet engines to surge or drop in power rapidly.
the harrier jet famously suffered from this issue in a huge way, and had a few crashes as a result.
the problem was literally the hot air though, not really due to a lack of oxygen... the harrier had a turbofan engine that had a decent bypass ratio, hence the exhaust gas still had lots of oxygen. hot air is alot less dense though, its like flying at 20,000 feet, then flying at 100', then 20,000 feet... that was what caused the surging.