Cisco ASR 9000 Series Manual page 14

Site Requirement Guidelines
Router Type
Cisco ASR 9922
Cisco ASR 9912
The fan trays maintain acceptable operating temperatures for the internal components by drawing in cool air
through the air filter, and circulating the air through the card cage. Each power supply is also equipped with
fans that draw cooler air into the front of the power supply and force warmer air out of the back of the chassis.
For information about the types of fan trays used in the chassis, see
Cisco ASR 9000 Series Aggregation Services Router Hardware Installation Guide
14
Chassis Air Flow
Air circulated by four fan trays as shown in
ASR 9922 Router—Side View. Two fan trays are located between the line cards
in the top cage and the RP and Switch Fabric Cards (FCs) in the middle cage.
Another two fan trays are located between the middle cage and the line cards in
the bottom cage.
Air is circulated by two fan trays located on upper rear side of chassis as shown
in Figure 13: Air Flow Path through the Cisco ASR 9912 Router—Side View ,
on page 18.
Preparing for Installation
Air Flow Path through the Cisco
Power Module Fans.