Technical Specifications

Designing a Liebert XD Solution

3.8 Liebert XDO Placement

3.8.1 Determining Spacing of Liebert XDOs in an Aisle

Liebert XDO modules should be placed in rows directly above the cold aisles of a room for optimum

cooling. Each Liebert XDO serves an area equal in width to the cold aisle spacing, typically 12 to 16

feet (3.7 to 4.9m). The length of the area served includes any space between Liebert XDO modules in

a row. Depending on the cooling capacity to be achieved, spacing between Liebert XDO modules in a

row may vary from zero to as much as 6 feet (1.8m). When the spacing increases to more than 6 feet

(1.8m), overall performance of the system may be negatively affected and gaps in cooling may occur.

Install one Liebert XDO at the end of each aisle being cooled and to space the remainder between

these end modules as shown in Figure 16. This layout will block the incursion of hot air around the

side of the end cabinets. Allowing space between the Liebert XDO groups facilitates maintenance by

allowing access to the overhead space.

Figure 16 Liebert XDO spacing—horizontal (side view)

Front-to-rear spacing of pairs

of Liebert XDO modules

XDO height above

equipment to be cooled

Heat-Generating Critical Equipment

Pairs of Liebert XDO modules

above critical equipment