Acer AR180 F1 - Manual (Page 54)

3 System upgrades 36
2 Remove the top chassis cover while the system is still running to
determine which of the fans has failed.
3 Remove the fan module.
(1) Push the fan clip handles inwards.
(2) Pull the fan up and away from the chassis.
4 Install the new fan module.
(1) Insert the new fan into the chassis.
(2) Push downwards until firmly seated.
5 Observe the post-installation instructions described on page 25.