Fan Thoughts

[Stoney]

Right just a quick question with the thought of summer coming up i am worried about the heat in my growroom they are 2 wardrobes and im thinking of getting an exhaust fan of some sort now i have 2 options that i have seen so far and they are

1. 20-25cm toilet exhaust fan that i could simply attatch to the roof of me wardrobes and would simple suck warm air out

 

2. a computer fan attached to some ducting and then attached to me light shade thus makeing a cheap air cooled light shade

 

any thoughts would be great as i have started looking for some

 

cheers guys by the way i use a 400w hps

 

[jaguarrh]

hey stoney...

 

i went to town with my ventilation. from what i've read (quite a lot on ventilation) the bigger the better.

 

a couple of questions, u knew u were gonna get them...

 

are you gonna be using a carbon filter?

 

what is the volume of the space?

 

[stonedstump]

Hey stoney,

 

I've got two of those bathroom fans you speak of. One is 250mm and standard sort of fan they do about 220L per second which is quite good.

 

I also have a 300mm that has movable blades so you can angle the blades to blow what way you want. I'm not sure what airflow rating it has but it would be more than the other one I'm sure.

 

Computer fans are not really any good except for fluroescents etc It depends what light you have but those bathroom fans are quite cheap and work well.

Edited July 18, 2006 by stonedstump

[pipeman]

having a fan extracting directly from the hood always helps.

 

if you can duct your cabinet exhausts to outside the room the cupboards are in that also will be helpful in keeping temps down.

[Ozzy420]

Hey stoney, there is a dude that sells the barthroom type of fan that is it a high rated fan, it moves 880lpm like the hydro turbo ones you get from the hydro shop and they are the type you can have running all the time.

 

The dude has then buy it now for $69, i have one and it was money well spent...

[thc24]

Hey stoney,

 

I've got two of those bathroom fans you speak of. One is 250mm and standard sort of fan they do about 220L per second which is quite good.

 

I also have a 300mm that has movable blades so you can angle the blades to blow what way you want. I'm not sure what airflow rating it has but it would be more than the other one I'm sure.

 

Computer fans are not really any good except for fluroescents etc It depends what light you have but those bathroom fans are quite cheap and work well.

 

 

hi there ive had many bath fans 300mm (turbos) most ive heard them moving was around 250 litre per minute or hour unsure if your right on the litre seconds that fan is a monster out powering my centrifigal same size.

 

 

 

when shopping for a fan you must have some requirements in mind and size of room, such as does it need to push through a filter or duct a bath fan does neither well unless its centrifugal or squrill cage and air is free flowing no bends or restriction in duct.

 

A inline fan (bigger motor but same style as bath) will push through maby 3 meters of duct but not filter, go to a shop and use the canfan chart to size fan to room and method of extraction.

 

in my room a 250 mm centrifugal on a filter only just empties room every minute 1.3 x 3.0mx 2m height = 7.8 cubic meters of air needs to be moved every minute.

 

Bath fans are ideal if you just want to move air from inside grow room to out but then air is recycled all depends what you want from the fan. you will need good size inlet holes because these fans dont suck all that well. the bath fan in pic would work ok 1x per light this is a large one 300mm with extra blades is called turbo something only bought at hydro shops but are expensive for the price of three you could buy a centrifugal or a massive inline.

 

Other pic is the fan and filter i replaced with.

 

Happy shopping do it once right for the cheepest option i think ive tried them all bath to inline to centrifugal.

 

Now days you can buy hybrids of centrifugal and inline they are best for where duct is used but dont do filters $$ isnt that good though only $50 less than same size centrifugal.

Edited July 18, 2006 by thc24

[Ozzy420]

That 2nd pic of the barthroom type fan is like the one i have...

[stonedstump]

Yeah that white fan in the picture you posted ozmade, that fan is the same as my 250mm fan except mine is black and the brand is "HPM".

 

 

I found the specs for it on hydroshop.com.au, here is a link to the page http://www.hydroshop.com.au/Products/Stock...asp?stockNo=265

 

They say 220L per second I reckon it would be about right but your fan might be slower than mine I don't know.

 

I have a 4.5 cubic metre space to ventilate. So I think that is 4500L of air? You would have to move 7800L then I think.

 

I've never connected my fans up to ducting before ozmade, can you tell me how much it effects the airflow? I would of thought the ducting would not make a different seeing as its a sealed pressure tube?

 

But I have been told be a few people that the longer the ducting the less air that will make it to the other end.

[Frazz]

Hey THC....have you got two filters on that fan ?

[Ozzy420]

That was thc24 post with the pics of the fans but anyway .

 

But yer the longer the ducting the stronger the fan u will need to push the air through it.

 

This is the fan i got off ebay ( http://cgi.ebay.com.au/Exhaust-Fan-250mm-B...6QQcmdZViewItem ) and it hasent given me an ounce of trouble and for my size grow it dose the job very well.

Edited July 18, 2006 by ozmade