What are vent fans used for?

Hi,

Im at the part of my build where I would out cooling.

I notice there are a lot of cheap vent fans out there such as this one:

http://www.aussieponics.com/index.php?route=product/product&path=63_88&product_id=104

I assume I this wouldn't be effective when connected it up to a DIY carbon filter but would it do the trick on a cooltube. I plan to give my cooltube its own intake and exhaust separate from the tent.

Thanks

well its a cheap budget axial vent, my canal ventilation (sum thing like this ) pull twice as much at the same size (6" pulling about 480 CMF)

But as a secondary ventilation just to keep the cool tube cool it might do the trick as long as you have a prober ventilation for the room/tent for fresh air/co2

For a main ventilation it would only be good for a small closed CFL/LED stealth grow IMO

Use it in a sealed line with your cool tube and use a prober ventilation for the room where you can add a active carbon filter that match the CMF of the ventilation (or bigger so it can handle the pull)

here is a chart on how to set the main ventilation up




sum thing like this:

or this

can get em in 4, 5 and 6 inch and also 8 and 10 inch for the bigger gardens, 4-6" are normally enough for smaller gardens depending on size and ambi temperatures aso

make sure it can empty the room in 1-5 minutes

Etc:
every 1 minute if you run some big ass bare 1000W HIDs in there, every 3 minutes if you have a single 600W and every 5 minutes if you maybe have a single 400W in a tube IME


Best of luck

Slip

You want somethings that's gonna move some air.
The more air moving over the bulb the cooler the light will be.
The link you have is a in-line fan.
You want a Centrifugal in-line blower 6" with 6" flexible duct work for you 6" cool tube.
You will be able to use the in-line blower to exhaust the grow room, and cool the bulb.
You can always get a speed controller down the road.

Good Luck on Your grow.

Slipon said:

here is a chart on how to set the main ventilation up

View attachment 3014746


sum thing like this:

View attachment 3014747 or this View attachment 3014748

Click to expand...

That chart is bang on to how I intend to vent the tent itself. Im hoping I don't need a expensive fan just for the cooltube. Its a 6inch and will have a 600w globe in it.

topfuel29 said:

You want somethings that's gonna move some air.
The more air moving over the bulb the cooler the light will be.
The link you have is a in-line fan.
You want a Centrifugal in-line blower 6" with 6" flexible duct work for you 6" cool tube.
You will be able to use the in-line blower to exhaust the grow room, and cool the bulb.
You can always get a speed controller down the road.

Good Luck on Your grow.

Click to expand...

I will use a Centrifugal for the grow tent then something cheaper for the cooltube on its own.

I know I could pull the air from the tent into the cooltube then into a carbon filter and out but Im thinking I will be better off putting the cooltube on its own intake & exhaust as my tent is fairly small (2x3x5)

Centrifugal blowers can do a much better job of coping with static loss in ductwork.

singa4 said:

I know I could pull the air from the tent into the cooltube then into a carbon filter and out but Im thinking I will be better off putting the cooltube on its own intake & exhaust as my tent is fairly small (2x3x5)

Click to expand...

nop, but what you could do is add the cool tube in between the filter and ventilation using some Alu Ducting

so its: filter - ducting - cool tube - Ducting - ventilation - and out the room

that would pull hot air trough the filter, pass the bulb and out the room, so you end up with odor free hot air removed, then you just need 2-3x the size (6") passive intake holes, so physic can replace the air going out (make sure to keep a slight underpressure/negative pressure in there so you know all air going out is pass the filter)

Slipon said:

nop, but what you could do is add the cool tube in between the filter and ventilation using some Alu Ducting

so its: filter - ducting - cool tube - Ducting - ventilation - and out the room

that would pull hot air trough the filter, pass the bulb and out the room, so you end up with odor free hot air removed, then you just need 2-3x the size (6") passive intake holes, so physic can replace the air going out (make sure to keep a slight underpressure/negative pressure in there so you know all air going out is pass the filter)

Click to expand...

If you are going to use a cooltube, you want to pull air from outside the grow room not from inside the room, and push air through the light so as not to run all the heat through the fan and cause premature fan failure.

Odor control should be a separate system, I understand this mean's spending more, but doing it right will save you from headaches later

I did run my cool hood with a filter on for about a year (before I made the switch to LEDs to over come the heat problem) and I had no problems adding the filter with some ducting on one side and let the odor free air pass trough the hood and out the room

like this



just make sure the ventilation is strong enough and take in to account the filter will restrain the ventilation and make it about 30% less effective, plus the ducting will as well, so make sure to keep it short and with a minimum of bends and don't make em to sharp

You can set your inline blower up 2 ways.
For winter you take cool air from outside.
in summer if you don't have a A/C for the grow room
You take the air from the grow room. to help keep it cool.

The bad thing about pushing the air through the duct work.
You also push that air through any holes you have.
I've had my in-line blowers for 6 years they suck the warm air.
Very good point about heat and bearings, but IMO they can handle that little bit of heat.

What ever way you decide to hook it up your on the right path getting a decent in-line blower.
You'll be happy you didn't skimp on exhaust.