User's Manual

1.1.13 Air Vent
An internal fan creates airflow through the vents, preventing your
notebook from overheating.
When it gets hot, your notebook will switch on the fans, which may
make some noise. This is normal, and does not mean there is a
problem.
Never block, push objects into, or allow dust to gather in the air vents.
Doing so may damage your notebook or cause a fire.