Thought I would share my recent (and 1st) experiences with using PC fans for a grow box. If you are not a pro with AC/DC currents, you may want to read.
I read a ton of info and a number of internet posts simply said to us any old AC/DC adapter like from a cell phone or laptop. I thought, Great! I have a couple of those PC adapters and some old cell phones lying around. I went to the computer store and spent $42 bucks on two very nice PC fans with covers. My plan was to wire one for internal circulation and other for exhaust. After splicing wires and wiring up (and researching serial vs. parrallel) they didnt work. I noticed what I thought was an inline fuse (bad idea.. it was a resistor to limit ohms) and bypassed that. Wired back up the fans to the DC AC adapter. It took all of about 2 seconds to smell burning. DAMN. Turns out that stupid ass laptop adapter is 18v! Also MOST laptop chargers are 18v. Why? Because they need to be able to charge your battery AND run your computer at the same time. Makes sense. Fans were toast.
Next step.
I found my old Blackberry charger. It is only 5v. Turns out that most phone chargers are 5v. This is OK though, and not a risk to burning out the fans.. it just might not run them very well. I bought a third fan (another $12) and wired it up to the berry charger. It worked ok, but not a lot of air movement.
Next, I went to Radio Shack to see about a 12V AC DC adapter. They have several of them. None were perfect and ALL were crazy expensive. $40 bucks for a 50 cent Chinese piece of crap. However, I DID find a 4-pin splitter that takes one power source and gives you 2. For $5 I got it. Beats the twisted wires and such.
Anyway, to make a longer story into a solution. I finally started over and here is what I recommend:
I found this on Amazon (I love amazon) Coolerguys 100-240v AC to 12 & 5v DC 4pin Molex 2A Power Adapter.
http://www.amazon.com/gp/product/B000MGG6SC/ref=oh_details_o01_s01_i02?ie=UTF8&psc=1
$15 shipped via Prime. Then hooked up to my new PC fan. OMG! That little fan kicks ass! It has to be pushing 400% more air than what it was doing from the BlackBerry charger. The fan is rated to 74 cfm and even with screens and thin filters on both sides, it is exhausting more than enough air. Going out and getting that second (4th overall) fan after work today.
So, do yourself a favor and dont make my mistakes. DONT use a laptop charger and a phone charger is not enough power. Make sure it is 12V. Get the 4-pin adapter and fans that are prewired for this. Molex connection I think it is called.
Good luck and happy growing!
DD
I read a ton of info and a number of internet posts simply said to us any old AC/DC adapter like from a cell phone or laptop. I thought, Great! I have a couple of those PC adapters and some old cell phones lying around. I went to the computer store and spent $42 bucks on two very nice PC fans with covers. My plan was to wire one for internal circulation and other for exhaust. After splicing wires and wiring up (and researching serial vs. parrallel) they didnt work. I noticed what I thought was an inline fuse (bad idea.. it was a resistor to limit ohms) and bypassed that. Wired back up the fans to the DC AC adapter. It took all of about 2 seconds to smell burning. DAMN. Turns out that stupid ass laptop adapter is 18v! Also MOST laptop chargers are 18v. Why? Because they need to be able to charge your battery AND run your computer at the same time. Makes sense. Fans were toast.
Next step.
I found my old Blackberry charger. It is only 5v. Turns out that most phone chargers are 5v. This is OK though, and not a risk to burning out the fans.. it just might not run them very well. I bought a third fan (another $12) and wired it up to the berry charger. It worked ok, but not a lot of air movement.
Next, I went to Radio Shack to see about a 12V AC DC adapter. They have several of them. None were perfect and ALL were crazy expensive. $40 bucks for a 50 cent Chinese piece of crap. However, I DID find a 4-pin splitter that takes one power source and gives you 2. For $5 I got it. Beats the twisted wires and such.
Anyway, to make a longer story into a solution. I finally started over and here is what I recommend:
I found this on Amazon (I love amazon) Coolerguys 100-240v AC to 12 & 5v DC 4pin Molex 2A Power Adapter.
http://www.amazon.com/gp/product/B000MGG6SC/ref=oh_details_o01_s01_i02?ie=UTF8&psc=1
$15 shipped via Prime. Then hooked up to my new PC fan. OMG! That little fan kicks ass! It has to be pushing 400% more air than what it was doing from the BlackBerry charger. The fan is rated to 74 cfm and even with screens and thin filters on both sides, it is exhausting more than enough air. Going out and getting that second (4th overall) fan after work today.
So, do yourself a favor and dont make my mistakes. DONT use a laptop charger and a phone charger is not enough power. Make sure it is 12V. Get the 4-pin adapter and fans that are prewired for this. Molex connection I think it is called.
Good luck and happy growing!
DD
