How to wire a computer fan?

Discussion in 'Growing Marijuana Indoors' started by EChillin, Aug 24, 2007.

  1. Hey guys, I was thinking about using a computer fan to serve as my exhaust fan. I think 2 or 3 of em will fit the bill just fine, but I'm not sure how to wire them since they have the power connectors that would hook into a computer power supply. Any advice on how to power these? any other exhaust recommendations? my grow space is 3x2.5x2.0
  2. clip off the end and wire it like lamp. I think the power from your wall (220 watts, 120volts) is too much so I would get a 12 volt batt. like a Zap scooter batt. and run it off that. At least see if it will work.

    I think they are a 12 volt fan so don't go over that and you should be fine.

    Wait I just looked this up: If there is any one component that is absolutely vital to the operation of a computer, it is the power supply. Without it, a computer is just an inert box full of plastic and metal. The power supply converts the alternating current (AC) line from your home to the direct current (DC) needed by the personal computer. In this article, we'll learn how PC power supplies work and what the wattage ratings mean.

    I'm not an electricial so this is only a guess

    Sorry I couldn't help more.

    Also you could use a bathroom fan from home of depot thats what I do in my closet when I dry mine. It keeps the smell out of my room and keeps the humidity down.
  3. uhm. Dont listen to anything posted above.

    Go find a Nokia charger or any other charger that has a 12v DC output. Look at the amp ratings (will be in milliamps), as long as the one on the fan is lower than the one on the charger your good to go, you can even hook up multiple fans to one charger as long as the amps add up right.. Almost always the charger wires dont say which is positive and which is negative so your gonna have to try that on your own. Nothing should blow up, the fan will only turn on once the you got the wires the right way so dont be afraid of wiring it wrong because the fan just wont turn on. After that your all done. Plug the charger in the wall and you have a mini fan :)
  4. Thats cool I expected a reply like that it's what happens when I smoke. Things come out the ass end and not the mouth. LOL

    Sorry about the wrong reply to that one.

    Det de de, I sometimes like to think I know more than I accually do when stoned.

    I just talk/write before thinking. Bad habbit of mine...:mad:
  5. u can also use the power supply of a computer with no computer. its easy to rig just jump some wires. REALLY SIMPLE if ur intrerested check the thread in my sig or pm me Ill tell u how.
  6. I just wired up a few computer fans in an idea of mine to use a CPU box as just a light box, with a hole cutout and the plant sitting in soil in a rubbermaid container below.

    You need:
    1) ATX Computer Power Supply (look for a big plug with a green wire, if it doesn't have a green wire, its not right)
    2) 12 volt Fans
    3) Wire Strippers
    4) Electrical Tape or Wire Nuts
    5) Some extra wire

    Step 1: Clip the Green Wire and a black wire (any of them it doesn't matter, there is normally one right next to the green wire) and wire nut or tape them together.

    Step 2: Clip the yellow wire (this is your 12+) and another black wire (again does't matter which one they are all grounds)

    Step 3: Wire nut the yellow wire to the positive wires from your fans and wire nut the black wire to the black wire from your fans.

    Step 4: Plug-in the power supply and the fans should start running. Never perform any work on it without it being un-plugged. You may want to get some looming to wrap around the wires, just for extra protection.

    Extra: You also have 5 volt (red wire) and 3.3 volt (orange) connections on a power supply so you may be able to rig other things to run off it as well. I had the power LED light on the computer rigged to the power supply so I could just look at the front of the computer to know if the fans were running and it also makes it even more stealth because the computer looks and sounds on.
  7. I have like 10 phone chargers and none of them are 12V :(
  8. A DC motor (like that in a PC fan) will run on lower voltages than what it is rated for. It will run slower though.


    Any 12v DC adapter (I use one of those multi adapters with the end cut off.)
    And wire them together, test it to make sure its blowing the correct way, if not switch the wires around.

    its really that simple
  10. so if my phone charger is like 5v, i can still run my fan, it will just run slower? in case its helpful, my charger is 5.7v/800mA, and my pc fan is 12v, .2A
  11. you can run 5 volts on a 12 volt pc fan but the fan will not work worth of crap.there Are pc fans that run on 5 volts.a cheap power supply can be had from radio shack.
  12. Get an old PC power supply, like anything that works, wattage and stuff doesnt matter at all. hook your fans to the molex connectors, and then use a paper clip wrapped in tape and bent over in a U shape (tape so you wont get shocked) to touch the green and brown wires going to the motherboard connector (the wide one with 20 or 24 pins). I'm not honestly shure its green an brown, I THINK so tho, might google it, just look for something like "hotwiring ATX power supply". But if you have a paper clip with the tape, shoud be ok anyway.... or might hold it in pliers with grips on the handels. the right prongs SHOULDNT shock you, but they can, and it would suck if you touched one of the wrong ones... REALLY suck.

    Oh, and all you need to do is touch the pins for a second, not hold it on them.

    An easier thing may to be just find any old computer in a dumpster. You can either take out the PSU and do what i said, or if you dont want to, use it in the case or take the PSU and motherboard, and use the pins that go to the power button on the motherboard to start it.

    I know this is badly written, but if you can figure it out, and have half a brain an can understand simple electronics, you can do it lol....

    (edit) for the way with the motherboard, use a screwdriver, penny, anything to short accross the 2 pins that had a mini plug and circut going to the power button, that will start it, and it wont shock you, no need for insulation)
  13. Yeah, you should run all computer fans on 12v. Nokia chargers are pretty cheap. I prolly have 10 laying around here. Computer fans come in 60, 80, and 120 mm. Low velocity 120 mm fans will be much quieter than high velocity 60 mm fans, even when they move the same amount of air. Radio Shack fans are cheaply made and noisy. I would use or in the US or Canada. Panasonic Panaflow fans are nearly silent in comparison to cheapies. I have Vantec thermostatic fans in my PC case. One more thing, computer fans are accessories in most electronics stores. The profit margin on them is in excess of 400%. A $20 case fan at a big box store will cost you $5 online. You won't find a quality fan at any price at most electronics stores.
  14. I just used a cell phone charger that was the right levels. Just cut off the wires and attach them to the fan.
  15. you bette off blowing $12 at a homedepot on a heating assist fan their small and designed to assist a heating vent in cirrulating home heat, they are 120 and can be fashioned easy to your needs........................peace,,,,,,why make it harder than it has to be.:smoke:
  16. I am using computer fans on my box... they work fine.

    what you will need...
    1. AC/DC converter 12v 1000ma w/voltage select(lower mA the less power per fan)
    2. 12v 80mm cpu fans (4)
    3. electrical tape

    I have tested a few designs on making these, i even have one that works with a thermostat. The better the converter you get the better your fans will work... 1000ma ones gave me the best results. all you have to do is cut the adapter plugs off of both the adapter and all the fans... for the fans you wanna twist all the pos and the negs to form one pos and one neg wire... then take you converter wires and connect and tape. then there you go... you have some fans and you can control their speed with the voltage selector.

    i dont use my fans at the full 12 volts that they can use... im usually running them at about 7-9 volts but you can run them at 12 volts with the 1000 ma adapter for a full light cycle. lower mA adapters tend to over heat if you push them too much... so if you do use a smaller mA adapter dont run it at the full 12 volts.

  17. Hey man im right there with you, i just made my grow room and i have been looking at different venting options for a couple of days now. I too came to the conclusion of computer fans. Problem being im not an electrician, but i am a computer technician. So i say fuck having to re wire everything. Get an old power supply and throw in a couple fans. The power supply is cheap, already made, the computer fans connectors already fit the connectors on the power supply. And you can put like 8 fans on 1 power supply. It even comes with its own on/off switch.

    Best of luck
  18. Thats a really good idea aliensworkshop. But arn't those used to power an entire computer also? Wonder if it would be equivilant to leaving a PC on 24/7. 8 fans 24/7 might be the same anyways lol.
  19. True true, but whats the difference if you have 4-8 fans all on different plugs. A computer supply runs a 115V. Good point tho im not sure how expensive it is to run a computer all the time. In the office i work in we have 10-20 computers running 24/7 365 days. Not to mention the 4 servers we have running and our electric bill is nothing to complain about. Im just saying i would rather possibly pay a couple of bucks extra a month to run off of something with a ground and that hasn't been tampered with. Then to run my own shit wiring and burn my house down.
  20. The only way I see it causing a problem is if you had some 12v fans running off of a 30v adapter. But if you have to have a lot of fans running in a box I'm sure the power supply would be the best way. you can get those plug adapters to so that you can attach more fans/hardware also correct so if you needed more than 8? Also they sell small power supplies for PC to correct? maybe just get a smaller one

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