Acer AR380 F1 - Manual (Page 62)

3 System upgrades 44
2 Place the air duct on the chassis so that the tabs on the air duct
align with the slots on the chassis.
Caution: Do not pinch or unplug cables that may be near or under
the air duct.
3 Observe the post-installation instructions described on page 27.
Replacing a system fan
The system has four high-performance PWM fans to provide the
cooling for the system. Fan speed may be controlled by a setting in
BIOS (see Chapter 4).
To replace a fan module:
1 Perform the pre-installation instructions described on page 26.
Warning! The system fan becomes very hot when the system is on.
Allow it to cool off first before handling.
2 Remove the top chassis cover while the system is still running to
determine which of the fans has failed.