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The ultimate beginner's guide to PC FANS
- Thread starter ScrubNinja
- Start date
StrangeVisitor
Member
newGroath, you want the air in your grow chamber change every 3-5 min.
If I got you right, you have 40 by 40 inches square and 70 inches high. That's 3.33ftx3.33ft and 5.83ft.
here's a few numbers that might help you:
Volume is 3.33x3.33x5.83 = 65 cubic feet roughly.
Air change ratio: 65ft^3/3min = 21,6CFM.
So you need to find fan a fan that is close to 25CFM. I would even go for a 35-45CFM fan to have some extra power if needed.
You have an air scrubber and possibly light traps so you'll want to have a higher rated fan with good air pressure spec (more than 20 mmh2o), the more the merrier. And you might want it not to be too noisy (less than 40dB or 1 sone).
Any other details about your setup? What kind of air filter are you going to use?
If I got you right, you have 40 by 40 inches square and 70 inches high. That's 3.33ftx3.33ft and 5.83ft.
here's a few numbers that might help you:
Volume is 3.33x3.33x5.83 = 65 cubic feet roughly.
Air change ratio: 65ft^3/3min = 21,6CFM.
So you need to find fan a fan that is close to 25CFM. I would even go for a 35-45CFM fan to have some extra power if needed.
You have an air scrubber and possibly light traps so you'll want to have a higher rated fan with good air pressure spec (more than 20 mmh2o), the more the merrier. And you might want it not to be too noisy (less than 40dB or 1 sone).
Any other details about your setup? What kind of air filter are you going to use?
Thank you for the help on this, I'm going to try and build this filter https://www.icmag.com/ic/showthread.php?t=29402
I'm guessing I'll have to size it down to the size fan I'll be using . But also I've been thinking of stacking the fans to increase the airflow .
Am going to be running fluorescent lighting ,starting off with a 150 watt 6500k cfl and and 32watt ones maybe about 8 of those..
I'm guessing I'll have to size it down to the size fan I'll be using . But also I've been thinking of stacking the fans to increase the airflow .
Am going to be running fluorescent lighting ,starting off with a 150 watt 6500k cfl and and 32watt ones maybe about 8 of those..
BuhBeeLawnFall
Member
What a usefull thread.
StrangeVisitor
Member
newGroath, welome! How doing?
Active intake doesn’t sound like a good idea to me if you are going to filter the air – they may case odor leaks or restrict the airflow. You don't want to have heat issues, you know. But you need to mix the air in the growchamber well .
You are planning to use a 150w 6500K CFL for the beginning switching later to 256w of fluorescent (not total 400w of light), did I get it right? Lamps aren't separated with glass? Ballasts inside or outside? Have you got the carbon for the filter?
S.V.
Active intake doesn’t sound like a good idea to me if you are going to filter the air – they may case odor leaks or restrict the airflow. You don't want to have heat issues, you know. But you need to mix the air in the growchamber well .
You are planning to use a 150w 6500K CFL for the beginning switching later to 256w of fluorescent (not total 400w of light), did I get it right? Lamps aren't separated with glass? Ballasts inside or outside? Have you got the carbon for the filter?
S.V.
All is well over here , and you?
I meant that when I stack the fans it'll be for the exhaust im going to do the passive intake definitely, and maybe some fans clips to the side to blow air around
No glass between a the lamps just a fan blowing on them to keep it cool. And the lamps have built in ballasts even the 150 watt
I meant that when I stack the fans it'll be for the exhaust im going to do the passive intake definitely, and maybe some fans clips to the side to blow air around
No glass between a the lamps just a fan blowing on them to keep it cool. And the lamps have built in ballasts even the 150 watt
StrangeVisitor
Member
Not bad, thanks!
Your thought was to put fans one after another so they could help each other? I guess it’s better to have one sufficient fan to do the job. And it’s worth getting a speed control for a powerful enough fan rather than having a mess of different fans that will make noise not airflow. In my opinion if you get a ~90CFM fan with good pressure rating (15-20 inches h2o / 40-50 mm h2o) to pull/push through the scrubber you’ll be fine. The pressure the fan develops is crucial; the volume it pumps is secondary. And another thing to mention – the volume the fan is able to pump falls when the air resistance it has to deal with grows. The CFM rating of the fan shows how much air it pumps with zero restriction. The pressure rating is shown for pumping into a “dead end”.
If you use 8x32w lamps you’ll have 256w total and that doesn’t sound like a lot for your footprint in terms of heat. But you need to do your ventilation right anyway.
The filter resistance to airflow depends on the coal faction used. Generally the smaller faction used - the greater resistance will be. And it is quite a common problem to find activated coal. The diy filter you found looks nice - just like manufactured.
Let the experienced guys here correct me if I’m wrong.
You are on the right way, man, keep it goin’!
Sorry for my poor English.
P.S. Much thanks to ScrubNinja and others who’ve contributed here! It’s a must read thread!
Your thought was to put fans one after another so they could help each other? I guess it’s better to have one sufficient fan to do the job. And it’s worth getting a speed control for a powerful enough fan rather than having a mess of different fans that will make noise not airflow. In my opinion if you get a ~90CFM fan with good pressure rating (15-20 inches h2o / 40-50 mm h2o) to pull/push through the scrubber you’ll be fine. The pressure the fan develops is crucial; the volume it pumps is secondary. And another thing to mention – the volume the fan is able to pump falls when the air resistance it has to deal with grows. The CFM rating of the fan shows how much air it pumps with zero restriction. The pressure rating is shown for pumping into a “dead end”.
If you use 8x32w lamps you’ll have 256w total and that doesn’t sound like a lot for your footprint in terms of heat. But you need to do your ventilation right anyway.
The filter resistance to airflow depends on the coal faction used. Generally the smaller faction used - the greater resistance will be. And it is quite a common problem to find activated coal. The diy filter you found looks nice - just like manufactured.
Let the experienced guys here correct me if I’m wrong.
You are on the right way, man, keep it goin’!
Sorry for my poor English.
P.S. Much thanks to ScrubNinja and others who’ve contributed here! It’s a must read thread!
HerBnGorE(illa)
Member
Subbed
StrangeVisitor
Member
You can try to find out the info about the fan googling the part number on the sticker. But if it is a stock fan it's not likely to find anything about it.
Anyway, a PC fan won't fit your purposes. They are good to move air around, not push through a canlike filter. You need to find something from HVAC equipment. A fan I see for your system is something like TDM-100 (SOLER & PALAU) or Blauberg Turbo 100 or 125. Or any other brand, I don't know what is common and available in your country. You can get a general idea of a fan needed googling those I mentioned. Check out their specs and diagrams. You'll see what you need. I'm not sure it is permited to post links, so just search for the info and models. Yes, it's going to take some time.
A very powerful (and noisy!) PC fan may pump somewhere close to 100CFM, very few models though, but there is no axial computer fan that can get even close to the pressure needed. Some of them can do 5-7mmh2o (most of them do about 2mm or less), while you need at least 10 times more.
BTW, in the very first post ScrubNinja has covered most of the questions on the fans and particularly pc-fans. All I'm doing here is retelling the information already available in this thread. That post and the whole topic is worth reading - you'll get answers for most of your questions.
Cheers!
Anyway, a PC fan won't fit your purposes. They are good to move air around, not push through a canlike filter. You need to find something from HVAC equipment. A fan I see for your system is something like TDM-100 (SOLER & PALAU) or Blauberg Turbo 100 or 125. Or any other brand, I don't know what is common and available in your country. You can get a general idea of a fan needed googling those I mentioned. Check out their specs and diagrams. You'll see what you need. I'm not sure it is permited to post links, so just search for the info and models. Yes, it's going to take some time.
A very powerful (and noisy!) PC fan may pump somewhere close to 100CFM, very few models though, but there is no axial computer fan that can get even close to the pressure needed. Some of them can do 5-7mmh2o (most of them do about 2mm or less), while you need at least 10 times more.
BTW, in the very first post ScrubNinja has covered most of the questions on the fans and particularly pc-fans. All I'm doing here is retelling the information already available in this thread. That post and the whole topic is worth reading - you'll get answers for most of your questions
.Cheers!
StrangeVisitor
Member
Hi, newGroath!
To build a decent growbox you need to invest a bit, yes. It’s not cheap as many ppl think at the first hand. My PCgbox cost me roughly 200 bucks counting only the components and it’s with a pc case I was lucky to pick for less than 10 bucks! Not to mention the instruments, work and countless drives to the retailers. And that is all with an average wage in my country just slightly higher than 200, man.
Nevertheless, let’s get to our business )).
PCfans are wonderful for moving air inside of a reasonably large microgowbox. But to use ‘em you need a power supply. 12v or an adjustable one (like 1.5v-3v-4.5v-6v-7.5v-9v-12v). And it should have enough amperes for all your pc-fans + some more (to start an electric motor you need more power than for running it). It’s another piece of equipment in your box and a pricy one too. I’ve got Meanwell RS-12-15 (12V, 15W=1,5A) and it cost me about $20. A bright side is that it’s very compact, overload and short circuit protected and is really powerful for its size. It is an industrial one – we are using such PSU’s in our racks sometimes.
Taking all upper mentioned into account you might be interested in running all your ventilation on the AC power? I find this variant easier and maybe cheaper to make but you should be real accurate with the entire electricity job and need a fuse/automatic circuit breaker for sure. I guess you have 110V/60Hz power grid? Anyway, you’re connecting your lights to the AC power, so the AC vents won’t make the entire thing more complicated. Good news is that there are ac vents with clips and safety grids/covers over them easily available anywhere. I’d love to use those in my setup if I had more space. And be sure all the electrical contacts are done really, really well&right. An easiest way to make the connections is to use "Wago Connectors 222". You have to only take the isolation off, insert the cable and close the clamp. Really easy and doesn't require any additional instruments. If you follow the instructions – you can be sure everything is OK.
Buddy, not looking down at all, but it’s a waste of time to teach grammar if one doesn't know the words. It’s for your own benefit to know more about all this stuff, too. I’ll be glad to be of some help for you or anybody else if I can. And I don’t mean to sound rude – it’s just my lev of English that sucks.
Keep us posted about your assembly. Maybe here is a special forum for building reports or smth like that?
Take care,
S.V.
To build a decent growbox you need to invest a bit, yes. It’s not cheap as many ppl think at the first hand. My PCgbox cost me roughly 200 bucks counting only the components and it’s with a pc case I was lucky to pick for less than 10 bucks! Not to mention the instruments, work and countless drives to the retailers. And that is all with an average wage in my country just slightly higher than 200, man.
Nevertheless, let’s get to our business )).
PCfans are wonderful for moving air inside of a reasonably large microgowbox. But to use ‘em you need a power supply. 12v or an adjustable one (like 1.5v-3v-4.5v-6v-7.5v-9v-12v). And it should have enough amperes for all your pc-fans + some more (to start an electric motor you need more power than for running it). It’s another piece of equipment in your box and a pricy one too. I’ve got Meanwell RS-12-15 (12V, 15W=1,5A) and it cost me about $20. A bright side is that it’s very compact, overload and short circuit protected and is really powerful for its size. It is an industrial one – we are using such PSU’s in our racks sometimes.
Taking all upper mentioned into account you might be interested in running all your ventilation on the AC power? I find this variant easier and maybe cheaper to make but you should be real accurate with the entire electricity job and need a fuse/automatic circuit breaker for sure. I guess you have 110V/60Hz power grid? Anyway, you’re connecting your lights to the AC power, so the AC vents won’t make the entire thing more complicated. Good news is that there are ac vents with clips and safety grids/covers over them easily available anywhere
. I’d love to use those in my setup if I had more space. And be sure all the electrical contacts are done really, really well&right. An easiest way to make the connections is to use "Wago Connectors 222". You have to only take the isolation off, insert the cable and close the clamp. Really easy and doesn't require any additional instruments. If you follow the instructions – you can be sure everything is OK.Buddy, not looking down at all, but it’s a waste of time to teach grammar if one doesn't know the words. It’s for your own benefit to know more about all this stuff, too. I’ll be glad to be of some help for you or anybody else if I can. And I don’t mean to sound rude – it’s just my lev of English that sucks.
Keep us posted about your assembly
. Maybe here is a special forum for building reports or smth like that?Take care,
S.V.
HerBnGorE(illa)
Member
What a great thread. Been going through it gathering all the excellent information. Thanks to all who contributed.
Anyone have experience with a Noctua NF-A14 industrialPPC-3000 PWM Fan (140x140x25mm 4-pin PWM, 3000rpm max., IP52) ?
Specs
10.52 mm/H20 (0.37 in)
269 m3/h
41.3dB
The static pressure is the same the Solar & Palau TD-100xs on low. Might this be enough to use an actual carbon filter?
Specs
10.52 mm/H20 (0.37 in)
269 m3/h
41.3dB
The static pressure is the same the Solar & Palau TD-100xs on low. Might this be enough to use an actual carbon filter?
Hey, I'm wondering the same thought ! 158 cfm / 10.52 mmH20. Seems like a good fan for the purpose.
*edit spelling.
