Cooling System and Airflow in a PTX10002-36QDD

The cooling system in the router consists of three dual-rotor fan modules for the chassis and a single built-in fan in each power supply unit. The router supports front-to-back airflow. We ship the router with 2+1 redundant fan modules preinstalled in the rear panel.

The fan modules are hot-insertable and hot-removable FRUs: You can remove and replace them without powering off the router or disrupting router functions. The fan modules are installed in the fan module slots on the rear panel of the router. The fan module slots are numbered 0 through 2 from left to right. Each fan module slot has a fan icon and a fan module status LED next to it.

Each fan module weighs approximately 1.5 lb (0.68 kg).

1 — Captive screw	3 — Handle
2 — Airflow direction label

Note:

You must install all the fan modules, and they must be operational for optimal functioning of the router.
Under normal operating conditions, the fan modules operate at a moderate speed. Temperature sensors in the chassis monitor the temperature within the chassis.

If a fan module fails or if the ambient temperature inside the chassis rises above the acceptable range, Junos OS raises an alarm. If the temperature inside the chassis rises above the threshold temperature, the system shuts down automatically.

Figure 1: Airflow Through the Router

Figure 2: Fan Module Status LED

Fan module status LED

Table 1: Description of the Fan Module Status LED
State	Color	Pattern	Description
On	Green	On steadily	The fan module is working normally.
On	Green	Blinking	The initiation of the fan module software is in progress.
On	Red	On steadily	The fan module is faulty.
On	Amber	On steadily	One of the fans in the fan module is faulty.
Off	—	—	There is no power supply to the fan module.