content_image/999303.jpg
A generic example of hot and cold airflow and the arrangement of server aisles is shown in Figure 10-2. 

<img src='content_image/999303.jpg'>

As shown in Figure 10-2, rows of servers must be placed front-to-front. Chilled air is provided through perforated floor panels that are placed in rows between the fronts of servers (the cold aisles). Perforated tiles generally are not placed in the hot aisles. 

If your computer room causes the temperature in the hot aisles to exceed a comfortable temperature, add as many perforated tiles as necessary to create a satisfactory comfort level. Heated exhaust air exits the computer room above the computing equipment. 

For more information about the requirements for air-cooling options, see IBM 3907 Installation Manual for Physical Planning,  GC28-6974. 

## 10.2 Physical specifications 

This section describes the weights and dimensions of z14 ZR1 server. The z14 ZR1 is the first IBM Z server that is based on a 19-inch rack; therefore, dimensions and weights are significantly different from previous generations of IBM Z servers. 

The z14 ZR1 can be installed on a raised or non-raised floor. For more information about weight distribution and floor loading tables, see the IBM 3907 Installation Manual for Physical Planning,  GC28-6974. This data is used with the maximum frame weight, frame width, and frame depth to calculate the floor loading. 

