Artesyn Centellis 4100 Installation and Use (2015) - Manual (Page 143)

FRU Installation
Centellis 4100 Installation and Use (6806800D82E) 145
4. If you want the shelf manager to be informed about the extraction, set the handle
switch of the replacement blower to the Closed position. If not, continue with the
next step.
Operating the shelf with the top front cover removed for more than 30 seconds may cause
the shelf to steadily heat up and possibly start to power down.
Unless an internal fuse has blown (not field replaceable), blowers are never actually powered
down.
If the red LED is on (the rightmost LED), an error has occurred in the blower. If the control
board has failed, the blower will be operating at 100% speed.