> Replacing the Chassis' Air Filter
> The lower fan draws air into the chassis. It is equipped with a particulate air filter to prevent dust and debris from entering the system. The air filter must be changed periodically to ensure proper ventilation and air flow through the chassis.
> IMPORTANT: It is recommended that you replace the air filter at least every six months. Keep a minimum of one replacement air filter on site for each deployed chassis. This ensures that qualified service personnel can quickly replace the filter when needed. It is also recommended that the filter be replaced during a maintenance window.
> To order replacement air filters, use part number 600-00-1105.
> ESD During installation, maintenance, and/or removal, wear grounding wrist straps to avoid ESD damage to the components. Failure to do so could result in damage to electrical components and could potentially void your warranty.
> Determining When an Air Filter Needs Replacing
> If the air filter is replaced at least every six months as part of routine maintenance, there should be no need for out-of-cycle replacement. However, under certain conditions, the air filter may need replacement between maintenance periods.
> One possible indication that an air filter needs to be replaced is if the chassis temperature remains high for extended periods of time. This condition causes the dual speed fans to run at high speed. A clogged and dirty air filter could hinder air flow through the chassis and result in higher operating temperatures.
> To monitor chassis temperature and fan speed, issue the following command in the CLI’s Execute mode:
> show fans
> The following is a sample output for this command:
> Upper Fan Controller: State=All Running Speed=Normal Temp=20 (C)
> Lower Fan Controller: State=All Running Speed=Normal Temp=20 (C)
> To monitor the temperature of individual cards, enter the following command in the CLI’s Execute mode.
> show card info slot_#
> This command displays operational information, including the temperature for the card installed in chassis slot_#, which can be any integer value between 1 and 48.
> The system supports Simple Network Management Protocol (SNMP) traps that are triggered for conditions that may indicate the need to change the air filter:

> SNMP Trap | Description
> starFanSpeed | The speed of the fans controlled by this fan controller. The value normal(1) represents the normal operating speed of the fans. The value high(2) represents that the fans are running at a higher rate of speed. Fans running at a higher temperature may be the result of a dirty air filter.
> showCardTemperature | The temperature, in degrees Celsius, as measured on the card. A value of 0 indicates that the temperature cannot be read or that the card is not present. The maximum measurable temperature is 70°C. The safe operating temperature range for the chassis and its sub-components is between 0 and 55°C.
> starCardTempOverheat | The card has reached a temperature beyond its safe operating range. The safe operating temperature range for the chassis and its sub-components is between 0 and 55°C.
> starCardTempOK | The temperature of the card is currently within its safe operating range. This notification is only generated if the card has previously generated a starCardTempOverheat notification.

> Removing the Old Air Filter
> Follow the instructions below to remove the system’s old air filter.

> 1 | Access the chassis’ lower fan tray assembly.

> a | Remove the plastic bezel from the lower-front of the chassis by placing your fingers in the notches on its sides and pulling it toward you.

> b | Use a #1 Phillips screwdriver to remove the fan tray cover. Loosen the four screws that secure it in place and pull it away from the chassis.

> 2 | Raise the plastic tab above the face of the fan tray assembly and gently pull it toward you until the air filter is free from the fan tray assembly.

> CAUTION: Do not operate the chassis without the air filter installed for extended periods of time. Doing so will cause dust to build up within the system, possibly hindering air flow and clogging open connector ports.

> 3 | Discard the used air filter.

> 4 | Proceed to the Installing the New Air Filter section that follows.

> Installing the New Air Filter
> Follow the instructions below to install the system’s new air filter.

> 1 | Verify that the direction of the arrows located on the sides of the air filter point upwards. This indicates the direction of the airflow into the chassis through the filter.

> CAUTION: Installing the air filter incorrectly may cause over-temperature conditions within the system.

> 2 | Slide the air filter into the lower fan tray assembly along the guides located on the lower fan tray until the front of the air filter is flush with the front of the assembly.

> 3 | Lower the plastic tab over the front of the fan tray assembly to secure it in place.

> 4 | Remove any dust build-up that may have accumulated on the chassis front air intake. This should be done as part of routine maintenance to continue optimum airflow into the chassis. The front air intake is located on the lower fan tray cover.

> 5 | Replace the fan tray bay cover and tighten each of the four screws to secure it to the chassis.

> IMPORTANT: The fan tray cover is keyed and can only be installed in one direction.

> 6 | Replace the plastic bezel over the fan tray bay.

> a | Align the bezel over the bezel mounts that protrude from the fan tray bay cover.

> b | Snap the bezel in place.

Cisco Systems Inc.
Tel: 408-526-4000
Fax: 408-527-0883