Juniper QFX5220, Hardware Manual, Page: 56 / 247

CAUTION: The system raises an alarm if a fan module fails or if the ambient temperature
inside the chassis rises above the acceptable range. If the temperature inside the chassis
rises above the threshold temperature, the system shuts down automatically. The system
takes 240 seconds to shut down after the red alarm threshold is reached.
Do not mix fan modules with different wattage. Only use the replacement fan modules that are designed
for use with your product number. See Table 13 on page 56 for the correct part number for your QFX5220
device.
CAUTION: Do not mix AC and DC power supplies in the same QFX5220 chassis.
However, if you need to convert a QFX5220 device to have a different airflow, you can change the airflow
pattern. To convert an AIR IN product variant to an AIR OUT product variant or an AIR OUT product
variant to a AIR IN product variant, you must power off and replace all of the fans and power supplies at
one time to use the new direction. The system raises an alarm when the system is converted, which is
normal.
NOTE: If you change the switch to have a different airflow, be sure to update your JTAC install
base to reflect the new configuration to ensure service warranties and contracts remain˙.
QFX5220-32CD Fan Module LED
On the QFX5220-32CD switches, the fan module LEDs are located on the chassis next to the fan module
slot. Figure 18 on page 59 shows the location of the fan module LEDs next to the fan module on a
QFX5220-32CD switch.
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