APC SGI 15000 RAID - Manual (Page 136)

122 007-5510-002
Symptom Cause Action
If the ambient air is cool
(below 25 °C) and the fans
are observed to increase in
speed, then some restriction
on airflow may be causing
additional internal
temperature rise.
Note: This is not a fault
condition.
The first stage in the thermal
control process is for the fans
to automatically increase in
speed when a thermal
threshold is reached. This
may be caused by higher
ambient temperatures in the
local environment and may
be perfectly normal.
Note: This threshold
changes according to the
number of drives and PCMs
fitted.
1 Check the installation for any
airflow restrictions at either the
front or rear of the enclosure. A
minimum gap of 25mm at the front
and 50mm at the rear is
recommended.
2 Check for restrictions due to dust
build-up; clean as appropriate.
3 Check for excessive re-circulation
of heated air from rear to the front.
Use in a fully enclosed rack
installation is not recommended.
4 Check that all Blank modules are in
place.
5 Reduce the ambient temperature.