Active Carbon Can Filters

[McBudz]

Newb question...

Looking at these carbon filters with the flanges I'm trying to figure out which end of the airflow do they get connected to? Does air get pulled in through the filter or does the filter go on the end of the fan duct where air is exhausted?

When it is rated at a certain cfm does that mean your fan should be less then rated cfm for filter or more?

Thanks

 

[wwilde]

I pull air through mine which I believe is the most efficient way & my inline fan has a higher CFM rating than the filter.

Correct me if I'm wrong?

 

[Boss]

I think most are designed to be pushed through, but mine pulls through as well, otherwise I would have to put it outside my room, or build a box around it and attach a 4" vent to the wall.

 

[wwilde]

^^ Yes thats why it seemed the simplest way

 

[MayorGreenBud]

the brand can fan, is meant to pull air through the filter.

filter, flange, fan.

 

[McBudz]

Thanks all.

Would this suffice in treating the smell I have in my spareroom from the grow in the closet? I'd hate to drop over 100 on a filter and still have the smell. What are others doing in closet grows for odor control?

 

[StonerGrower]

The carbon filter is all I need. Of course you can still smell it a little in the growroom, but in any other room in the house there are no traces.

 

[Drummingstar1]

if you are using a canfan with the right cfm rating for the room, you won't smell a dang thing! You could stand directly under the vent exhaust, and will not smell anything resembling a marijuana plant. it's amazing!

 

[stonedinla]

THANKS FOR THE INFO i WAS GETTING SMELLS THROUGHOUT THE HOUSE I LIKED IT BUT NOT THE BUG MAN HAD ME WORRIED SHUT HER DOWN TILL I SOLVED THE PROB

 

[WeedyMcWeedWeed]

you want to pull the air through the filter. and im guessing you want the same or more cfm for the fan

 

[Setting Sun]

If you use a fan with too high CFM for your filter, it won't work well because the air won't be in contact with the carbon long enough to filter it properly.

You want to be somewhere around the filter's CFM requirement.

They work better if you pull air through them rather than push.

 

[WeedyMcWeedWeed]

how do you know what size carbon filter to get for a certain size room??

 

[Setting Sun]

how do you know what size carbon filter to get for a certain size room??

If your carbon filter is going to be a part of your heat exhaust system, the first thing to consider is how much heat you need to remove from the grow room.

That will drive the decision as to what the exhaust fan's CFM rating should be, then match your carbon filter's rating to your fan.

 

[WeedyMcWeedWeed]

so the sizes of carbon filters are all just for different cfms? so what would be the best route for a 3'x3' tent with a 400w HPS? to have 1 fan scubbing snd exhusting all hot air.

 

[Setting Sun]

so the sizes of carbon filters are all just for different cfms? so what would be the best route for a 3'x3' tent with a 400w HPS? to have 1 fan scubbing snd exhusting all hot air.

It would depend on your ambient temps.

My tents are about that size and I'm using 100 CFM fans, which keep my temps at 4-6 degrees above ambient, but the climate where I live is usually mild, and ambient temps in my garage are generally somewhere between 60-90 degrees year-round.

I run my lights at night so that my tents don't get too cold.

What kind of ambient temps are you dealing with?

 

[WeedyMcWeedWeed]

well to be honest idk what kind of temps my room stays around. in my closet, my rooms is between 72-82* with the door open. if i completely close it, it can get up to 90*. with that said, im sure my room probably averages a little bit cooler. i have not grown in the winter here, so idk what kind of ambient temps im gonna have.

 

[Setting Sun]

Here's a simple formula that will give you a starting point and should get you at least somewhere in the ballpark:

"Air Exchange

As mentioned earlier, air exchange is a key ingredient to a successful grow room. The ideal air exchange rate will vary at different times of the year and from room to room depending on things like grow room height, etc. As rough guide about 30 air changes per hour is often recommended.

In addition to simply exchanging the air in the room to replenish the depleted co2, you need to keep it cool, this requires more air movement than replenishing the co2. I use this math equation:

A 90 CFM fan with a 600 watt light will raise your temperature above the intake air temp by 21°. The 240 CFM fan will raise it 8°. 90 CFM wouldn’t be enough. It’s not the size of the cabinet that you want to take into consideration; it’s the wattage being used. Watts produce heat.
(600 × 3.2) ÷ 90 = 21.33
(600 × 3.2) ÷ 240 = 8
To find how much the light will warm the room with a different size fan you can just use this formula. Just take the wattage of the light and multiply by 3.2. Then divide the CFM of the fan to find how much the room will warm in Fahrenheit degrees.
For instance:
If the temperature of the intake air is 75° and you’re using a 600 watt light, the temperature would go up 5° if you used a 384 CFM fan. So, the temperature would end up 80°.
(600 × 3.2) ÷ 384 = 5
5° + 75° = 80° "

 

[WeedyMcWeedWeed]

ok thanks man

 

[Setting Sun]

ok thanks man

No problem weedy .

I just re-averaged my temps and I'm running around 6 degrees above ambient.

Plugging my 250w light into the above formula puts me at 8 degrees above ambient, so it's pretty close and using it to estimate things should be better than just buying stuff and not knowing how it's gonna work until you hit the switch.

regards,

setting sun

 

[WeedyMcWeedWeed]

exactly. thats what i was looking for. thanks alot SS