Acer Altos R920 Series User Manual page 71

Determining fan status
Each fan or fan assembly has an amber LED to indicate a failed fan
condition. If the amber LED is on, the fan assembly needs to be
replaced. The LED remains off during normal operation.
To remove the front system fan assembly:
1 Observe the ESD precautions described on page 39.
2 Remove the front bezel. Perform the instructions described in "To
remove the front bezel" section on page 41.
3 Locate the fan assembly you are replacing. If a fan in the assembly
has failed the amber LED will be lit (A).
4 Press the green button on the front of the fan assembly to release
the handle (B).
5 Use the handle to pull the fan from the system (C).
To install the front system fan assembly:
Warning! To ensure proper system cooling, the replacement
of a failed system fan module should be completed within
one minute.
1 If necessary, remove the old front system fan assembly. See
previous section.
2 Slide the new fan into the fan bay (A).
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