The sound you hear could be the middle fan trying to turn on bad bearings. If you can replace just one fan, then try doing that and see if it fixes the problem. Or, if you have a spare fan,put it on there and see what it does.
As for the WPE, those are tought to diagnose without intimate knowledge of the system in question. Try to post the text of the error, if it displays it, and we might could go from there.
