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==Too much about fans==

If you have powered up more than three RAQs, you've probably encountered a bad fan.  It's pretty important to change bad fans out as they ''will'' lock up sooner or later and stop circulating air.  

The RAQ 3 and RAQ 4 use a small 12 VDC fan that is 35 mm square and 10 mm thick.  This is an industry standard dimension so there are lot of parts from a number of suppliers that will fit in the hole.  The original fan is a Sunon KDE1235PFB1-8.  This is a ball bearing fan that is rated at one watt of dissipation and will move about 5-7 CFM of air under ideal conditions.  There is a lower speed version that will move 4.5 to 6.5 CFM and is slightly quieter. It has 'locked rotor' protection - meaning that if the fan blade is blocked from moving the fan will not execute a 'halt and catch fire' operation.  Almost any manufacturer's fans will provide similar air movement performance for one watt of dissipation in this package. The one odd fact about the Sunon package is that it only provides three mounting holes where the industry standard is four. This is not a problem if you need to use someone else's fan with four mounting holes.  Almost all of the fans in this size only support the motor and blades from one side. This is the side that goes against the chassis.  When you install a new fan make sure that your fan lines up cleanly and doesn't block any of the air holes at all. There is so little area here that you don't want to lose any.