Some good points there which I shall definitely bear in mind. The fan motor can be chucked out and replaced with a standard fan module AFAIK with some minor rework.
Why can't a standard fan(12v or whatever) be fitted and just simply connected direct to a suitable supply rail, yes the fan would on all the time, but is that necessarily a bad thing?
That's a good question, and the answer is complex; but mostly it boils down to the nature of MOST axial fans: they are NOT meant to serve as a positive displacement air mover; they are meant as an air circulation device against zero head pressure/static load.
If you are trying to blow against a static load like a radiator or heavy grill, or in the case of a 2465, you are trying to pull a partial vacuum inside a sealed case so that air is drawn across specific components via strategically located air vents, then it matters VERY MUCH what kind of fan you use.
There ARE axial fans which are designed to move positive pressure against a static load; they have more powerful motors and a different airfoil shape and more aggressive pitch to the blades, and tend to be a lot noisier than their non-static-load-rated cousins. This is why Tek chose a
centrifugal fan/squirrelcage fan instead of an
axial/muffin fan.
However, it appears their solution was met with both reliability issues and customer complaint, so in later versions they did in fact revise to use a noisier static-load rated axial blower.
Myself, if I were replacing the fan due to complete failure, I'd look for a centrifugal blower of approximately the same size wheel and current draw and remove the outer shell so I could install it in the back cover. Or possibly a Noctua axial blower rated for static load, though it might be hard to find one small enough AND reasonably quiet.
Cheers,
mnem
Yes, I have spent entirely too much time thinking about this. Thank you for noticing.