Electronics Fan

[Slabman1]

I want to install a small fan in the wall of my water closet to circulate some conditioned air into that room, forcing it out under the door. (No heat/A/C in there) I hooked a 12V computer fan up to my car battery to check out the noise and it zapped the soldered connection for the wiring. Obviously, too much juice was going throught it. I'm told this should have worked, but now I'm confused about why I fried the thing. Do I need to wire in a resistor to lessen the amount of current seen by this fan?

[Guest]

Better to purchase a mains operated 4" fan supplied from a switched fused outlet and can use the ducting supplied if desired.