Cleaning the air filters
The air filters of a 12500E switch fall into the following types:
Chassis air filter—No chassis air filter is shipped with the 12500E chassis by default. You can order one as needed.
Power supply air filter—A 12500E chassis is installed with a power supply air filter when shipped by default.
To guarantee good ventilation of the switch and power supplies, HP recommends that you clear the air filters monthly. You must clean the air filter every three months at least.