Fan Timer

Originally Posted by bazookajoe

When I was using a cooler I used one of these fans with one of these adapters, and a timer like this. It was set to run for 15 minutes every 3 hours and kept the RH steady to within 2 points.

That's a good plug-&-play solution. Here's an alternative if you aren't afraid to cut some wires.

For the fans themselves, just about anything will work. Just search Computer fans and find one that looks good. You can find a lot of them for less than $10 on Newegg. Try to find one with only 2 wires. The 3 wire ones are adjustable speed, not really needed here.

Once you pick a fan, look for it's power requirement. For example:

Features
12VDC
Operation Voltage: 6.0~13.8 VDC
Rated Current : 0.16 A

So you need a power supply that will provide 12 Volts DC Output, with more than 0.16 Amps available.

This one does 12V with 500mA (0.5A) max. So you could hook 2 of the 0.16A fans to it if ya want (0.32A Total). Generally you don't want to load a power supply to it's max rating. try to keep the Amp use below 80% of max.

Then ya just cut the plugs off the fan and adapter and twist them together with some electrical tape around each pair and you should be good to go. Might want to do some testing to make sure the fan is turning the right direction.

Edit: A note on the timers too, as I've run into it before:

Make sure the timer you pick has the right number of holes for the plug on the adapter you choose. I picked up a great timer for a good price once and got home to find that the plug I was using was 3 prong (grounded), but the timer only took 2 prongs (not grounded).