Is the fan AC or DC?

120mm DC fans are probably most common for use in incubators. They move plenty of air and will run 24/7/365 for years straight.

I have four 120mm Scythe liquid ball bearing fans that have been running for over 7 years straight on a liquid cooled computer with no issues. Sleeved bearing fans are OK, single bearing fans are better, double bearing fans are a bit better yet, and liquid bearing fans are the best by far.

I have two incubators with single bearing fans running no problem.... one for over a year now, and the other just fired up with two 120mm fans. Wire them to a 12v AC/DC converter with a rheostat to control them to the desired speed, or just use an old 6v cell phone charger to run them half speed. I have two 120mm fans running off a 6v cell phone charger and another using a $15 AC/DC converter (which I will probably purchase another).

Here is the converter I used..... it is a charger for batteries and can be found at many hobby stores.

http://www3.towerhobbies.com/cgi-bin...&I=LXL353&P=SM

Some really good fans for fairly cheap..... 72cfm is plenty at full speed. I would run them at 1/2 speed on a 6v cell phone charger, or use a rheostat.

http://www.newegg.com/Product/Produc...82E16835119045

Both the fans in my newest incubator are these same EverCool fans in an aluminum housing.