Maintaining MX104 Cooling System Components
Maintaining the MX104 Cooling System
Purpose
For optimum cooling, verify the condition of the fans.
Action
The router has a single fan tray that installs into the front of the chassis, as shown in MX104 Universal Routing Platform Overview.
To check the status of the fans in the fan tray, issue the show chassis environment command. The output includes an entry for each fan in the fan tray:
user@host> show chassis environment
Class Item Status Measurement Temp PEM 0 OK 27 degrees C / 80 degrees F PEM 1 OK 18 degrees C / 64 degrees F ABB 0 Intake OK 29 degrees C / 84 degrees F ABB 0 Exhaust A OK 34 degrees C / 93 degrees F ABB 0 Exhaust B OK 36 degrees C / 96 degrees F ABB 1 Intake OK 29 degrees C / 84 degrees F ABB 1 Exhaust A OK 34 degrees C / 93 degrees F ABB 1 Exhaust B OK 36 degrees C / 96 degrees F Routing Engine 0 OK 31 degrees C / 87 degrees F Routing Engine 0 CPU OK 39 degrees C / 102 degrees F Routing Engine 1 Present Routing Engine 1 CPU Present AFEB 0 AFEB Processor OK 28 degrees C / 82 degrees F AFEB 0 LU Temp OK 40 degrees C / 104 degrees F AFEB 0 MQ Temp OK 38 degrees C / 100 degrees F AFEB 0 QX Temp OK 40 degrees C / 104 degrees F Pic PIC 0/0 Channel 0 OK 40 degrees C / 104 degrees F PIC 0/0 Channel 1 OK 40 degrees C / 104 degrees F PIC 0/0 Channel 2 OK 39 degrees C / 102 degrees F PIC 0/0 Channel 3 OK 39 degrees C / 102 degrees F PIC 0/0 Channel 4 OK 39 degrees C / 102 degrees F PIC 0/0 Channel 5 OK 28 degrees C / 82 degrees F PIC 0/0 Channel 6 OK 29 degrees C / 84 degrees F PIC 0/0 Channel 7 OK 28 degrees C / 82 degrees F PIC 0/0 Channel 8 OK 44 degrees C / 111 degrees F PIC 1/0 Channel 0 OK 45 degrees C / 113 degrees F PIC 1/0 Channel 1 OK 30 degrees C / 86 degrees F PIC 1/0 Channel 2 OK 31 degrees C / 87 degrees F PIC 1/2 Channel 0 OK 42 degrees C / 107 degrees F PIC 1/2 Channel 1 OK 29 degrees C / 84 degrees F PIC 1/2 Channel 2 OK 30 degrees C / 86 degrees F Fans Fan 1 Check Fan 2 OK Spinning at high speed Fan 3 OK Spinning at high speed Fan 4 OK Spinning at high speed Fan 5 OK Spinning at high speed
Meaning
Check is displayed in the Status column if a fan that is not functioning. OK is displayed in the Status column if the fan is functioning normally.
For further description of the output from the command, see the show chassis environment command summary in the CLI Explorer.
See also
Replacing an MX104 Fan Tray
Removing an MX104 Fan Tray
To prevent overheating, install the replacement fan tray immediately after removing the existing fan tray.
To remove the fan tray (see Figure 1):
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD point.
- Loosen the captive screws on the corners of the fan tray faceplate.
- Grasp the fan tray handle, and begin to pull the fan tray
from the chassis.
Warning To avoid injury, keep tools and your fingers away from the fans as you slide the fan module out of the chassis. The fans might still be spinning.
- Place one hand under the fan tray to support it, and pull the fan tray completely out of the chassis.

Installing an MX104 Fan Tray
To install the fan tray (see Figure 2):
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD point.
- Orient the fan tray in the slot so that the arrow is pointing up, and slide the fan tray straight into the chassis.
- Verify that the front of the fan tray is firmly seated in the chassis.
- Tighten the captive screws on the fan tray faceplate to secure it in the chassis.

Maintaining the MX104 Air Filter
Purpose
For optimum cooling, verify the condition of the air filter.
Action
Regularly inspect the air filter. A dirty air filter restricts airflow in the unit, producing a negative effect on the ventilation of the chassis. The filter degrades over time. You must replace the filter every 6 months.
Caution Always keep the air filter in place while the router is operating. Because the fans are very powerful, they could pull small bits of wire or other materials into the router through the unfiltered air intake. This could damage the router components.
The shelf life of polyurethane filter varies from two years to five years depending on the storage conditions. Store in a cool, dry, and dark environment. Wrap the media in plastic and store in an environment with relative humidity between 40%- 80% and temperature between 40°F (4° C) to 90°F (32° C). Note that if the material flakes, or becomes brittle when rubbed or deformed, it is no longer usable.
Replacing an MX104 Air Filter
Removing an MX104 Air Filter
Do not run the router for more than a few minutes without the air filter in place.
Always keep the air filter in place while the router is operating, except during replacement. Because the fans are very powerful, they could pull small bits of wire or other materials into the router through the unfiltered air intake. This could damage the router components.
The air filter must be installed on the right side of the fan tray. To remove the air filter (see Figure 3):
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD point.
- Remove the fan tray as described in Removing an MX104 Fan Tray.
- Press the release tab on the rear of the fan tray to release the air filter.
- Grasp the sides of the air filter, and slide it away from the fan tray faceplate.

Installing an MX104 Air Filter
The air filter installs on the right side of the fan tray. To install the air filter (see Figure 4):
- Wrap and fasten one end of the ESD grounding strap around your bare wrist, and connect the other end of the strap to an ESD point.
- Locate the THIS SIDE MUST FACE OUT label and ensure that the air filter is right side up.
- Insert the air filter into the groove located toward the front of the fan tray.
- Press the tab on the rear of the fan tray to allow the air filter to slide into place.
