Airflow Direction Requirements

All installed fan modules must blow air in the same direction and must match the airflow direction of the installed power supplies.

• If the fan module has a red tab, the airflow is front-to-back. Use a fan module labeled Air Out.
• If the fan module has a blue tab, the airflow is back-to-front. Use a fan module labeled Air In.

Note

The operating-system software cannot display the airflow direction.

Before you begin, have the replacement fan module on hand so that you can complete the replacement promptly. The switch can overheat if left without adequate cooling for an extended time.