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APPENDIX D — FAN FIELD REPLACEMENT PROCEDURE
A fan failure is indicated with a solid red STATUS LED on the OM front panel. When
a fan fails, it must be replaced to ensure proper airflow and cooling within the OM.
Fan replacement does not require powering down the OM, as each fan plug can be
disconnected from its power connector on the OM rear panel.
WARNING! Removal and replacement procedures have fan cover removed. Keep
hands away from fan blades and do not insert or drop objects into exposed fan
blades.
Fan Removal
Refer to Figure D-1 to remove a fan:
1.
Identify the failing fan, whose blade is not turning, on the rear panel of the OM.
(A failing fan blade does not turn, whereas a marginal fan may have a rasping
sound that is definitely a pitch off and also surges in volume from the steady
hum of other fans. In a rack of OMs, it is worthwhile identifying any marginal
fans to ensure adequate spares are available.)
2.
Remove the four hex nuts and washers securing the fan cover to the fan. Save
these, as they must be re-installed on the new fan.
3.
Slide the fan cover off of the four stand-offs.
4.
Unplug the fan power cable from its connector.
5.
Note the orientation of the fan cable. The fan blades face toward the OM and the
rear of the fan motor faces away from the OM. Slide the fan off of the four
stand-offs. Do not slide the base of the fan cover off of the stand-offs.