Juniper EX4300 Series Hardware Manual page 304

Each fan module is a hot-removable and hot-insertable field-replaceable unit (FRU) installed in the rear
panel of the switch: You can remove and replace it without powering off the switch or disrupting switch
functions.
CAUTION: Do not mix:
• Fan modules with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the
same chassis.
• Power supplies with different airflow labels (AIR IN (AFI) and AIR OUT (AFO)) in the
same chassis.
• Power supplies and fan modules with different airflow labels (AIR IN (AFI) and AIR
OUT (AFO)) in the same chassis.
• AC and DC power supplies in the same chassis.
NOTE: The fan module slots are at the left end of the rear panel on 24-port and 48-port
switches, and at the right end on 32-port switches.
fan module in 24- port or 48-port switches. The procedure is the same for 32-port switches.
1. Ensure that you have the correct fan module. The label AIR IN (AFI) or AIR OUT (AFO) on the fan
module must match the label AIR IN (AFI) or AIR OUT (AFO) on the installed power supply.
2. Attach the ESD grounding strap to your bare wrist, and connect the strap to the ESD point on the
chassis.
3. Remove the fan module from its bag.
4. Hold the handle of the fan module with one hand and support the weight of the module with the
other hand. Place the fan module in the fan module slot on the rear panel of the switch and slide it in
until it is fully seated.
Figure 87 on page 295 shows how to install a
294