All installed fan modules must blow air in the same direction and must match the airflow direction of the installed power supplies. 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.
A fan labeled Air Out provides front-to-back airflow for switch cooling. All 5520 Series switches are available with front-to-back airflow.
A fan labeled Air In provides back-to-front airflow for switch cooling. 5520-24T-BASE, 5520-24T-ACDC, 5520-24X-BASE, 5520-24X-ACDC, 5520-48T-BASE, 5520-48T-ACDC, 5520-48SE-BASE, and 5520-48SE-ACDC switches are available with back-to-front or front-to-back airflow.
