Ventilation Question

[MegaOctane12]

Ventilation question I need answering, two potential setups, which one would work better?

1) Carbon filter at the top of the room, connected directly to an extraction fan. Fan sucking air through the filter, blowing air through ducting into an air cooled reflector, ducting connecting the adjacent end of the reflector taking air out of the grow room.

2) Carbon filter at top of the room, filter connected directly to ducting, ducting connected to air cooled reflector, adjacent end of reflector connected to extraction fan at top of room. Fan sucking air all the way through the reflector, through the carbon filter.

[HARDDON]

If your carbon filter is designed to pull air thru and out, then you should operate it this way. Pushing air thru a filter that is designed to suck air will greatly shorten the life span of the filter itself.

Either way, as long as the top heat is removed you are fine. The air that comes out, if you unit is located at the top should be vented out and away from the grow area.

It will remove the higher levels of air heat and you need not screw with air cooled reflectors unless you are running dual 1000 watt lights.

a 1000W light with a fan on it does wonders...no need for special stuff...you can still get within 12" of the canopy.

Which is plenty.

But follow the designed air flow your carbon filter was built for.

[oldnslow]

I'vs always been a "fan" of pulling air thru anything rather than trying to push it with the Dayton squirrel cage fans. #2 would be my choice. That allows the possibility of creating a negative pressure room and that will easily allow you to totally control the incoming air, the temp, humidity, and co2 if used. All you need with a negative pressure room is an envrionmental controller. That will allow you maintain the best growth conditions day or nite, winter or summer. Good luck

[MegaOctane12]

If your carbon filter is designed to pull air thru and out, then you should operate it this way. Pushing air thru a filter that is designed to suck air will greatly shorten the life span of the filter itself.

Either way, as long as the top heat is removed you are fine. The air that comes out, if you unit is located at the top should be vented out and away from the grow area.

It will remove the higher levels of air heat and you need not screw with air cooled reflectors unless you are running dual 1000 watt lights.

a 1000W light with a fan on it does wonders...no need for special stuff...you can still get within 12" of the canopy.

Which is plenty.

But follow the designed air flow your carbon filter was built for.


Both options are 'sucking' air through the filter, maybe I should have phrased that better. The only difference is that one possibility would be too ehxaust the air through the reflector, the other is sucking air through it, does that make sense?




I'vs always been a "fan" of pulling air thru anything rather than trying to push it with the Dayton squirrel cage fans. #2 would be my choice. That allows the possibility of creating a negative pressure room and that will easily allow you to totally control the incoming air, the temp, humidity, and co2 if used. All you need with a negative pressure room is an envrionmental controller. That will allow you maintain the best growth conditions day or nite, winter or summer. Good luck


Yes that's what I originally expected, because air follows the path of least resistance. So you would have the fan seperate from the filter instead of the fan/filter together. One thing I don't like is the ehxaust, if you are blowing you are at least using the exhaust somewhat, it just seems like such a waste.


Any other opinions

[Racerx]

Another vote for pulling rather then pushing. It seems quieter in general too, but I could just be hearing things.

[HARDDON]

Wish I weren't so stoned...maybe I could help understand.

If you suck air in thru the filter, you are sucking indeed. But, if you are just blowing the air right back into the grow room, you are not accomplishing anything other than air scrubbing.

You are essentially placing hot air right back into the room from which it came from. That leaves little room for fresh CO2.

If you have a fan sucking air thru the filter, then you have tubing or other shit you are exhausting it thru, you are still PUSHING as well as sucking.

Hence the term vortex.

The end result is the same. These high end fans have extremely high static pressure levels and will push as well as pull. There is no difference and again, if you are dumping the air back into the grow area, even if thru vented hoods, you are only scrubbing the air.

Maybe when I not so high I can understand better....but I dont know when that time would be....

[Racerx]

Ok I was assuming that he was pulling air from one source and exhausting into another. That assumption, means you can simply pull air in from one source (that is probably going to be cooler then inside the grow room anyways) and then pull the air through a carbon filter, through the fan, and through ducting to a completely different area. If that is accomplished, you will be able to stabilize the environment fairly well.

PS. I agree that although aircooled hoods help, just moving air between the plant and the light will keep it pretty cool as long as there is some flow in the room.

[MegaOctane12]

I've drawn some pictures

[HARDDON]

Now that is dedication!

I can assure you....if you are using a high end VORTEX or CANFAN, the end results will be the same. Static pressure is high and either way, the same amount of air will be moved.

Pushed or pulled, the end result will be the same.

The only thing I might add...according to your plans, the exhaust MUST or SHOULD be far away from the intake.

These fans have massive power and will suck air from whereever it gets it.

Just make sure the exhaust does not get sucked back into the grow room. The plants have already used the air and need fresh CO2.

But again, you are accomplishing the same thing either set-up.

[dusto2k3]

i've been told by many it's better to pull air away from the heat source. ya know
:stoned:

[MegaOctane12]

Now that is dedication!

I can assure you....if you are using a high end VORTEX or CANFAN, the end results will be the same. Static pressure is high and either way, the same amount of air will be moved.

Pushed or pulled, the end result will be the same.

The only thing I might add...according to your plans, the exhaust MUST or SHOULD be far away from the intake.

These fans have massive power and will suck air from whereever it gets it.

Just make sure the exhaust does not get sucked back into the grow room. The plants have already used the air and need fresh CO2.

But again, you are accomplishing the same thing either set-up.


For sure, everything within the system is air tightened with duct clips and fast clamps if necessary. I'm not sure how well the lights will be cooled because the air will be taking in from the grow room, not outside, but hopefully the setup is such that the lights don't even get a chance to raise the grow room temperature a single degree. Passive intake at the bottom and a small occilating fan should help counteract any temperature increase. Will hopefully find a cheap 'environmental controller' so the ventilation is more effective.

[HARDDON]

Lights are going to raise temps...you can't avoid that.

Energy = HEAT no matter whether it's radio frequencies or light frequencies.

With those big vortex or canfans, you will need and want more than ONE passive intake. You will need and want several.

[hondo]

I would suck air thru the filter ,then thru the hood , and then thru the fan and out.
If you try to blow air thru a hood , you would have to seal the hood completely in order to keep from blowing hot air out around the glass ect..(unless its a cooltube) Where as sucking it thru the hood ,if you have a little air leak know big deal.
I would definately suggest getting the biggest fan you can afford(within reason)And I would suggest a CanFan
Using a carbonfilter, ducting and cooling a hood will cause a bit of static preasure,and i have found that the squirrelcage fans just dont cut the mustard when it comes to preasure.
I use a 8" Canfan HO 756cfm .I divided the duct into 2 6" ducts .1 duct cools 2 1000s and the other cools 3 400s.
Hope this helps

[Jdog7000]

Mine is set up like the second drawing.
The temp raises about 5 dgrees with the lights on.

[MegaOctane12]

Lights are going to raise temps...you can't avoid that.

Energy = HEAT no matter whether it's radio frequencies or light frequencies.

With those big vortex or canfans, you will need and want more than ONE passive intake. You will need and want several.

Thanks for the responses, I'll be using a 420m3/hour RVK fan and dialing it down. From experience, the 175m/hour are just too noisy working flat out consistently, I don't know how the fan will sound if I dial it down but I'm hoping it will make a difference.

[MegaOctane12]

I would suck air thru the filter ,then thru the hood , and then thru the fan and out.
If you try to blow air thru a hood , you would have to seal the hood completely in order to keep from blowing hot air out around the glass ect..(unless its a cooltube) Where as sucking it thru the hood ,if you have a little air leak know big deal.
I would definately suggest getting the biggest fan you can afford(within reason)And I would suggest a CanFan
Using a carbonfilter, ducting and cooling a hood will cause a bit of static preasure,and i have found that the squirrelcage fans just dont cut the mustard when it comes to preasure.
I use a 8" Canfan HO 756cfm .I divided the duct into 2 6" ducts .1 duct cools 2 1000s and the other cools 3 400s.
Hope this helps


The reflector would be sealed I'm guessing, haven't actually got the light yet. The thing is that the exhaust is much more powerful so I would have thought it would work better, someone said it makes no difference. I'm a bigger fan of sucking, I'll probaly be doing this, thanks.

[MegaOctane12]

Mine is set up like the second drawing.
The temp raises about 5 dgrees with the lights on.

:stoned: