I need to cool a small cabinet - roughly 4-5 cubic feet. Primary consideration is that it is QUIET. Silent would be better as this is in the family room and will be running 24/7 to keep some network equipment cool and un-crashed. (The Ethernet switch that runs indefinitely in free air will overheat and lock up after a few hours in the cabinet.)
There are plenty of “muffin” style fans out there that run on 120 volt AC power, with noise ratings from 29 to 65 dB. (I figured going with a line-powered fan would be simple and spare me from having to conjure up a power supply.)
Alternately, there are 240 volt fans. Strangely, the ones I’m looking at have no actual dB ratings other than “very quiet.” What sort of results might I be able to expect if I ran one of these on 120? Sample specs are 2700 RPM and 112 CFM. Am I right in guessing that this would yield about 60 CFM on 120? Or is this destined for failure as the fan tries to spin at its normal speed but draws twice as much current and cooks itself to death?
Does the fan have to be mounted on the cabinet? Or can it be remotley mounted and connected to the cabinet with a duct? A three or four inch duct can handle the small amount of CFM you need in this case.
Check Middle Atlantic’s website for something that’ll work. They have several different options as far as fans and how those fans are mounted that would probably work for your situation.
Yes, the fan needs to be inside the cabinet. Ductwork runing through the room (and then to where?) would be even less appealing to the spouse than a lost internet connection.
Mines, yes, those are the kinds of fans I’ve been looking at.
I can pick up 240-volt fans for dirt cheap on the surplus market. I just need to know if continuously running one at half its intended voltage will give me a silent breeze or if it will result in damage to the fan.
If dirt cheap, then pick one up and try it out. Plug it into 120 and see if it gets smoking hot, or if it stays cool, and if it’s going to give you the airflow you need.
To the basement? (The one you maybe don’t have in NC.) That would work in my house, cutting through the floor inside an interior wall. But maybe just through to the other side of a wall would be feasible.
I’m pretty sure you’ll just burn out the motor due to higher currents, as you mentioned in the OP. This is a source of damage during brown-outs.
Do you have any spare USB outlets? Old/spare computer parts?
On the USB cable, you’ll have that end of cable that will fit into the USB port. Snip the other end of that cable and strip the wires maybe an inch or two back. Take out an old computer cooling fan and connect to the usb cable, red to red and black to black . Plug the little DIY fan into the usb port and let it run. Position where heat buildup seems to be biggest problem.