Piping
20
3.4.2 Piping Mains
All refrigeration piping mains connected to the Liebert XD cooling module, both supply and return,
should be installed with a downward pitch toward the Liebert XDP of 1-2" for every 20 feet
(25.4-51mm per 6m) of pipe run.
Install a 20-40 mesh strainer on the chilled water supply to the Liebert XDP. The strainer is required
to prevent particles in the chilled water from entering the Liebert XDP’s heat exchanger. The
maximum distance from the strainer to the Liebert XDP is 10 feet (3m).
NOTICE
Risk of particles in chilled water. Can cause equipment damage and reduced cooling.
Failure to install a strainer in the supply line to the Liebert XDP can result in damage to the
unit’s heat exchanger.
3.4.3 Bypass Flow Controller
Three bypass flow controllers are required to ensure that the Liebert XDP pumps operate within the
optimum range. These devices are added to the field piping and simulate the flow of additional cooling
modules.
Each bypass flow controller must be installed with one shutoff valve to allow the controller to be
disabled when cooling modules are added to a Liebert XD system.
Bypass flow controllers should be connected between the main supply and the main return lines of the
field piping. The connection points to the main supply and return lines should be in a convenient and
accessible location between the Liebert XDP/Liebert XDC and the first Liebert XD module in the
circuit. See
Figures 20
and
21
for piping details of the bypass flow controller.
Refer to
Table 5
to determine the number of bypass flow controllers that must be open to provide
proper refrigerant flow based on the total nominal cooling capacity of the cooling modules in each
Liebert XD system.
Figure 20 Bypass flow controller details, dimensions
Table 5
Bypass flow controllers for a Liebert XDP-based system
System Load kW Cumulative
Module Model Size
Required Number of Open
Bypass Flow Controllers
Liebert XDP
48 to 63
3
64 to 95
2
96 to 127
1
128 to 160
0
7/8"
(22mm) ID
4" (102mm)
Содержание Liebert XDP
Страница 2: ......
