Technical Specifications

Designing a Liebert XD Solution
28
The assembly and connection means used for piping in the Liebert XD system are similar to that of
conventional refrigeration systems. All piping should be installed with high temperature brazed
joints. Soft solder is not recommended. The lines being brazed MUST be filled with flowing dry
nitrogen during brazing to prevent excessive oxidation and scale formation inside the piping.
Prevailing good refrigeration practices must be employed for piping supports, leak testing,
dehydration and charging. Failure to use good system practices may result in damage to the system.
Refer to the ASHRAE refrigeration handbook for general good-practice refrigeration piping.
Follow all guidelines in 3.13 - Liebert XD Piping System Design and 3.14 - Liebert XD Piping
Slope during installation.
Insulate all piping lines to prevent condensation in applications where the dew point approaches the
R-134a refrigerant temperature. This might occur where Liebert XD module piping is above a
dropped ceiling or in other areas not measured by sensors connected to the Liebert XDP or Liebert
XDC.
See Table 8 for recommended pipe sizes and Figure 27 for piping segment locations.
For additional information about piping connections, see the unit’s user manual: Liebert XDP, 16644;
Liebert XDC, SL-16671; Liebert XDO, SL-16666; Liebert XDV, SL-16626; Liebert XDCF, SL-16678;
Liebert XDR SL-16935; and Liebert XDH SL-17210.
Figure 27 Generic piping layout
Table 8 Supply, return pipe sizes for refrigerant loop
Pipe Function
Key to Piping
in Figure 27 Size / Equivalent Pipe Length
Liebert XDP supply line, from Liebert XDP supply
to farthest Liebert XD cooling module
a
1-1/8" OD for lengths up to 60 feet
1-3/8" OD for lengths over 60 but less than 175 feet
Liebert XDP return line, from farthest Liebert XD
cooling module to Liebert XDP return
B
2-1/8" OD for lengths up to 60 feet
2-5/8" OD for lengths over 60 but less than 175 feet
From any model Liebert XDO/Liebert XDH/Liebert
XDR supply to supply line of Liebert XDP
C
1/2" OD for lengths up to 10 feet
7/8" OD for lengths over 10 but less than 25 feet
From any model Liebert XDO/Liebert XDH/Liebert
XDR return to return line of Liebert XDP
D
7/8" OD for lengths up to 10 feet
1-1/8" OD for lengths over 10 but less than 25 feet
From any model Liebert XDV/Liebert XDCF
supply to supply line of Liebert XDP
C
1/2" OD for lengths up to 10 feet
5/8" OD for lengths over 10 but less than 35 feet
From any model Liebert XDV/Liebert XDCF return
to return line of Liebert XDP
D
5/8" OD for lengths up to 10 feet
7/8" OD for lengths over 10 but less than 35 feet
NOTE
To minimize the amount of refrigerant required, do NOT oversize the piping.
AC
D
C
D
B
AC
D
C
D
B
Liebert XDC
or
Liebert XDP
Liebert XD
Cooling Module *
Pumped
Refrigerant
R134 a
Liebert XDC
or
Liebert XDP
Supply
Lines
Return
Lines
Pumped
Refrigerant
R134 a
*Liebert XDCF,
Liebert XDH,
Liebert XDO,
Liebert XDR
or Liebert XDV
Liebert XD
Cooling Module *
Liebert XD
Cooling Module *
Liebert XD
Cooling Module *
To Chiller,
Condenser
or Drycooler
To Chiller,
Condenser
or Drycooler