Yes, I guess in most cases it runs fine without a fan.
For those people who have the noisy fan and do not want to use the unit without a fan, note that Penbex used a very poor quality fan.
If you get a decent replacement fan from an electronics or computer store you will in most cases not even hear there is a fan. It makes so much difference.
The replacement fan is found on some videocards and is a standard size. So it is just a matter of unscrewing and refitting.

The only problem you might encounter is that you can not find a fan with the same connector as used on the mainboard.
In that case just cut the cords on both fans and connect the old connector to the new fan.

 

I disassembled the unit (Centrios 1315117) today, and like you said, it was not very difficult to extract the fan.  Basically, unscrew all the little screws, locate the little plastic connector plug, and pull it straight out of the board. 

I've been running the unit without any fan and after five hours or so and quite moderate temperatures, I can't see why we even need this huge annoyance.  The fan has been a major PITA from day one and with it out of the way, the radio is finally useable.  Prior to this, it had collected dust on a shelf for a couple of years, which was a real shame as I really liked the idea of accessing 1000s of internet radio stations and streaming my music.

I'm really glad you created and still maintain this site.  Had I not encountered it, I would not have had the inspiration to work on the radio and get it running this weekend.

I also want to commend you for working on the firmware upgrades.  Nice to see that the internet radio part (the key strength of the device!) is actively being supported despite penbex's bankruptcy.  The upgrade process went extremely smoothly although it appears the unit doesn't support large-capacity usb keys (4GB+).  I managed to flash the firmware with a 1GB key, though.

Tremendous work.
Thanks

I have not had time to write the whole thing down but its actually fairly simple.
There are a whole bunch of screws that have to be removed.
Once that is done it is a matter of removing the fan and putting a new one inside.
Is there any special info you are looking for?

Have you completed your description of how to replace the noisy fan on these penbex radios?  I have exactly the same problem and would like to know the best way to reduce fan noise.

Bob

Since there are various issues with the fan being too loud or no fan at all and overhating I will post some information on the fan and how to replace it in the coming days.

First of all, lets locate the Fan on the back of the machine:

As you can see on the lower right hand corner there is a fan.
I just picked up a "Titan" replacement fan. I will open up the device and make photos while doing that.

more to come..