Tutorial Ventilation 101

[Sirus]

Sorry bout that Red, the light is 400W in an Xtrasun reflector a/c 6"

flange. Do you know of a quiet fan/filter combo? Would you still advise a

seperate fan exhaust for the light, or will just passing a fan over the lamp

do the trick? I don't want to be running everything full blast and have my

temps running high.

 

[guest 77721]

Hey Sirus,

I feel the best design is an Axial fan ventilating the lights using a vented hood or a cooltube with about 20-30*F temperature rise in the exhaust air. The big room growers stack up to 4 lights on common duct this way.

Ventilate the growbox with 1 - 5 minutes between airchanges or 1/5 air changes per minute for the volume of the room and size a fan and scrubber accordingly.

For your box, a S+P for the lights and a 4" computer fan and a Canfan 2600 for 42CFM is a workable combo.

Using all axial fans will run much stealthier than using a noisy blower.

 

[guest 77721]

You'll know after the 3rd week when the plants start to get fragrant whether you'll neeed the scrubber or not. You have to determine how stealthy you need to be based on your lifestyle and living conditions. At my house two nice plants in flower will greet you at the door without a scrubber.

I'm getting the hang of the ventilation needs for my future micro grow. I am wondering about the importance or need for a carbon scrubber in a separate mother/clone cabinet. Is it necessary or not?

 

[hoosierdaddy]

Red, I wanted to chime in here concerning cooled lights.
When we duct to and from a light ficture, be it a hood or a tube, the temperature variance between that situation and open lights is dramatic to say the least.
As an example, this morning before lights out, my garage was 65degF, floor of my flower cab (18" x 23" x 5+ ft tall) was 63degF, 12 inches above the canopy was 72degF.
I have a 150hps and a 400cmh in a tube in that space, cooling the tube with a $27 inline duct booster and changing cab air with a Stanley diy 6" on high.

 

[guest 77721]

Right you are, Hoosier!!!

It takes way less airflow to cool tubes and hoods with an unrestricted fan.

I don't know who started using the plugged up practice of a furnace filter and a large scrubber to do the one pass design. It sure is making the grow shop owners rich selling this overpriced stuff.

I've been sorting out growbox ventilation problems now for a couple years and there are way more guys with problems with the larger lights than successful ones.

 

[kiheibuilt]

You'll know after the 3rd week when the plants start to get fragrant whether you'll neeed the scrubber or not. You have to determine how stealthy you need to be based on your lifestyle and living conditions. At my house two nice plants in flower will greet you at the door without a scrubber.

Thanks for the reply, stealth is the utmost importance for me so I guess I use a scrubber.

 

[The 420 Wookie]

Hello guys, I have been reading this thread for a few days now, trying to fully understand most of this, aside from the super technical aspects.

I am planning on renting an apartment to live and grow in. I am hoping to find a reasonable 1 bdroom, and I want to run a 600W flip/flopped while perpetual.

I want to get the following equipment, and I would appreciate your feedback on the noise / smell / efficiency / overall solidarity of the idea, as I am a wee skeptical. I am not mentioning nutrients or small things like timers and what not, just the $$ items pretty much, in case someone has some better input.

-(2) Tents (either 3x3x6or7 or 4x3x7, whichever is cheaper since there's a lot of sizes that will be pretty good)
-(1) Lumatek 600w digital ballast, 2 cords and a rely
-(2) S+P 150? (This is what I gathered would be needed to push the air out the carbon filter fast enough to keep 600W worth of plants happy and smell free out side the room)
-(2) DIY pro whatever carbon filters from the DIY link-o-rama, which I highly recommend there's some nifty things I forgot about.

I plan to run each tent with individual fan and filter during each flip flop. So that any smell that may be wofting out of the tent vents, will most likely be pulled back in as intake and re-scrubbed. The fan will be mounted inside the cab to psh the air out the cool tube and down the filter, and creating negative pressure in the cab if I am not mistaken.

And that's about it, veg will fit somewhere in there... in a makeshift rubbermaid or in the bathroom or something.. But yeah I need more bowls thats a good place to end. fuck I hate paying for weed.

-wookie

 

[guest 77721]

Hey 420 Wookie - that's sounds like a good setup for an apartment. Let's start by figuring out your specs.

Room 3' x 4' x 7'
Area 12 sqft
Volume 144 cuft

Ventilation for Light Cooling
Maximum CFM @ delta T = 10*F = 190
Minimum CFM @ delta T = 30*F = 65

Ventilation for Air Exchange
1 ACPM = 144 CFM
1/3 ACPM = 48 CFM
1/5 ACFP = 29 CFM





Here are the fan ratings for two styles of Soler+Palau fans. The TD mixed vent line are Axial fans to move lot's of air without restriction. The Powervent are centrifigal blowers.

I'm going to propose a few fans and then we'll pick the winner based on final design if it meets spec.

CFM = 190 - This is to ventilate the light and tent without a cool tube.
TD-125 High Speed/ Low Speed - 197/149 CFM
TD-150 High Speed/ Low Speed - 273/193 CFM
Powervent 125x - 206 CFM

CFM = 65 - This is the cool tube spec with 30* F exhaust
120mm Computer Fan - 65 CFM with no scrubber

CFM = 130 - This is the two tents tied together with no scrubber 60*F exhaust
TD-100x High Speed/ Low Speed - 135/100 CFM

The Fan/Scrubber combo for 65 CFM is going to be trickier to fit.



Both the Can 33 and Can 9000 look good. The Can 2600 is too small.



To read the CFM for a fan/filter combo, find the point where the fan curve crosses the filter curve.

PV-100 and CF 33 look like around 60-65 CFM
PV-100x and CF 33 around 90 CFM

PV-100x and CF9000 around 105 CFM
PV-150 and CF9000 around 110 CFM

Looks to me like your best bet is the PV-100x and CF 33 combo for 90 CFM or the PV-100x and CF-9000. Now you can go shopping. If you want to DIY, get the spec's for the filters and make a copy.

We didn't take a look at the Mixed Vent fans with the scrubbers.



The TD-100x is unsuitable.

The TD-150 and CF9000 are a good combo at 90 CFM.

Hello guys, I have been reading this thread for a few days now, trying to fully understand most of this, aside from the super technical aspects.

I am planning on renting an apartment to live and grow in. I am hoping to find a reasonable 1 bdroom, and I want to run a 600W flip/flopped while perpetual.

I want to get the following equipment, and I would appreciate your feedback on the noise / smell / efficiency / overall solidarity of the idea, as I am a wee skeptical. I am not mentioning nutrients or small things like timers and what not, just the $$ items pretty much, in case someone has some better input.

-(2) Tents (either 3x3x6or7 or 4x3x7, whichever is cheaper since there's a lot of sizes that will be pretty good)
-(1) Lumatek 600w digital ballast, 2 cords and a rely
-(2) S+P 150? (This is what I gathered would be needed to push the air out the carbon filter fast enough to keep 600W worth of plants happy and smell free out side the room)
-(2) DIY pro whatever carbon filters from the DIY link-o-rama, which I highly recommend there's some nifty things I forgot about.

I plan to run each tent with individual fan and filter during each flip flop. So that any smell that may be wofting out of the tent vents, will most likely be pulled back in as intake and re-scrubbed. The fan will be mounted inside the cab to psh the air out the cool tube and down the filter, and creating negative pressure in the cab if I am not mistaken.

And that's about it, veg will fit somewhere in there... in a makeshift rubbermaid or in the bathroom or something.. But yeah I need more bowls thats a good place to end. fuck I hate paying for weed.

-wookie

 

[The 420 Wookie]

Well, let me start by saying I thank you very much for your time, and appreciate the lengths you went through to give me the best answer I could have expected. I am also very glad you think to be a reasonable endeavor. Confidence boost!. I am still re-reading your ideas, but am a little confused... and I wanted to address a point or two.... I hope it isn't too much of a bother.

Ventilation for Light Cooling
Maximum CFM @ delta T = 10*F = 190
Minimum CFM @ delta T = 30*F = 65

(I just dont undertand what this is meant for, its got something to do with the maximum or minimum temperature being exhausted.. but I dont know in which regard I am to use the numbers.)

Ventilation for Air Exchange
1 ACPM = 144 CFM
1/3 ACPM = 48 CFM
1/5 ACFP = 29 CFM

(EDIT: I understand now, and after re-reading up above I wonder how many ACPM do you think will be neccesary when the filter is attached to the fan and light?)

CFM = 190 - This is to ventilate the light and tent without a cool tube.

(Now I am sure that this ties in to the original temperature formula, so once the missing piece is connected in my head, this will probably make sense.)

CFM = 65 - This is the cool tube spec with 30* F exhaust
120mm Computer Fan - 65 CFM with no scrubber
CFM = 130 - This is the two tents tied together with no scrubber 60*F exhaust
TD-100x High Speed/ Low Speed - 135/100 CFM

(I just want to point out that I will have to run both cabs separately for the flip flop, and that I can not scrub them together, as I would like them to be 2 fully separate independent cabs. Also, I have not looked into the powervent series much as I have not read much about its super quietness?.. Where as the TD line has alot of reviews being super duper quiet and good for condos/apts. I would rather go with the TD 150, unless you have anything better to say about the PV 100x. Also, I cannot afford to buy carbon filters when I can make them for close to nothing. Another point, is that I want to use only 1 fan per tent to achieve basically no outside the room noise. Also, do you think it is wise to go without a cool tube and get the PV100x, and simply push out the air and scrub it?.. I am not sure I would get more lumens that way unless I got like a batwing reflector, as long as the heat is under control. EDIT: After re-reading above I guess I will put the filter closer to the groud and just put the duct upwards for the fan and light to out of the cab, since that wont let smell escape much, well better than filter on outside and air pushed through?. )

As for the scrubber/filter whatever, once I have the fan chosen, can I not just build a DIY scrubber to accommodate the fan?

Thanks again, I hope I didn't miss something, this time I got high before I typed.

-wookie

 

[guest 77721]

Hey Wookie,

I did put a bit of time into this but it's for a good cause. I really wanted to put all the fan curves and filter curves on the thread. You guys have never seen this stuff before!!!

I also wanted to give you all the rough specs so we could play around with various designs and see how they play out on the fan curves.

One of my other side projects will be to reverse engineer the CanFan spec's. This will give the DIY filter guys the ability to build and match the filter to the fan.

I was just looking up the filter spec's for you and the CF-9000 is unsuitable. It can pass 42 CFM max and up to 400 CFM for recirculation. If you blast the air through it, there isn't enough contact time for the carbon to work.

So your options now are each tent gets a PV-100x and the Canfan 33 using a cooltube. The CF 33 is 33cm tall with an 10" inner core and a 12" outer screen with a 2" carbon depth using 16.5 lbs of carbon. Sadly these fans are noisy and will probably sound like a vacuum cleaner.

Now, if you want to go a bit stealthier, I would recommend tying both lights and cooltubes together with a common TD-100x. This will cool both lights on at the same time and you can always run it low speed for one light. I'd get a couple of 6" axial computer fans with DIY filters with a carbon depth of no more than 1/2".

 

[The 420 Wookie]

I understand, I was going to say there was al ot of good information, just a lot of it was about things I knew would not suffice, but that will definitely help others in the same boat as me looking to go smaller, or spend money on real filters.

Relating to my tents though, you feel I should put them beside each other and put a duct running through both tents, with both cool tubes using the same duct, so the one TD100x will be running 24/7 to exhaust only the lights, on low speed, since only one light at a time will be on, but there will always be one on.

How exactly would I scrub this now?.. See I wanted to just run each cab independently as to filter only the cab during lights on. Do you not think this is a good idea?... I didnt mind buying 2 fans and making 2 filters, I thought it would be the stealthiest most secure way. I don't think I mentioned this frankly enough, but there can be no clues to people that I grow, unless they see me doing something plant related. I want to live in the apartment too, so I will be smoking, they wont think I'm growing, but if it always smells, that's a problem.
You've got me all second guessing myself now... Cant wait for your reply

-wookie

 

[guest 77721]

The ventilation requirements range from max of 144CFM @1ACPM to 29CFM@ 1/5 ACPM.

A CanFan 9000 is made for axial fans with 1/2" carbon depth. Get a 6" computer fan and make a DIY copy for each tent.

This is your stealthiest route with a single TD100x for the lights and two computer fans for the scrubbers.

 

[Giant]

Can I control multiple fans with a single controller? I have a Vortex 6" and a GrowBright 6" that are going to be too powerful for my Sun Hut XL tents. I would prefer not having to buy two controllers..

 

[guest 77721]

The problem with motors is that they draw quite a bit of power on startup, typically between 1.5 to 2.5 times the full load current. Two motors on the same controller would likely overload it on startup or low speed operation which also draws more current.

The Fantech controllers run $30-60 so it's not a major purchase like your fans. The risk is yours to take, buy one, blow it up and then end up buying 2 to get going for a total of 3.

 

[Giant]

So, what your saying is.. If I start one fan after the other, everything will be peachy?


Point taken.. So is that they way to go (fantech controller) over something like this http://www.horticulturesource.com/sunlight-supply-the-speedster-variable-fan-speed-control-p1665/

 

[guest 77721]

Oooh that speedster is rated for 120V/15A. That will start both fans. The fantech unit only had a rating of 2.5A.

BTW, in industry large fans, hydraulic pumps and motors with large loads use dampers, unloading valves and clutches to start the motor first and then apply load once the motor is up to speed.

If you had a speed controller that would run both motors but not start against the load, then you would need two dampers to block off each fan and then stage the starting.

 

[The 420 Wookie]

Hey Red, I just have a stupid question for you before I set off to buy my equipment. How do I actually scrub the air of the two tents with only the 6" computer fan, would I tape it into a 6" duct or something and then have that pull air through the filters in each cab when they are on?

 

[Sirus]

Here is another stupid question for ya...how would you connect

the axial fan to the filter/ducting? Just like Wookie I have money

in hand but after a couple months of reading up I'm still not sure

what will be the stealthiest setup for my cab

 

[MBA]

Red, I've read all 19 pages of this thread in hopes of finding a set up like mine will be, no such luck. I'll be building a 6'x6'x6' in a completly shaded basement with ambient outdoor temps and humidity quite high. I have to control temp & humidity,hopefully with a 5000btu window a/c, and a dehumidifier if needed, but can't add co2 because of stealth,this will be a sealed enviroment. I hope I can maintain 300ppm from small leaks and cracks? Planning on running a 600w with a 6" air cooled hood(total 8' long) maybee 6" ellbows on each end to block light,this would be the only restriction on the light vent. Planning fan and scrubber to work GREAT, what ever it takes??? If you're scrubbing the air and returning it in the same space does this create a balanced pressure or a accident waiting to happen? If it won't work,TELL ME! if you think its got a chance I would appreciate your opinons on fan size for lights, and fan and filter combo to make it work!!!

 

[RugerBaby]

I've also read all the pages on this thread but still am not getting it too well I suck at math. But if anyone would care to help me a bit I would really appreciate it!!

I currently have a 4ft x 4ft x 6.5ft grow tent. I'm also waiting on a 600 watt lighting kit with cool tube to arrive. My ambient temps are 68-70*F, and plan on exhausting through the attic, out the roof.

What would be the best setup to keep it cool and a good airflow?

All suggestions welcomed. I was really set on using one fan to pull through a filter+cool tube. But, im open to all combinations. Thanks