Emerson Liebert XDR - Manual (Page 22)

Piping
16
6.5.1 Brazing Preparations
The assembly and connection means used for piping in the Liebert XD system are similar to those
used for conventional refrigeration systems. All piping should be installed with high-temperature
brazed joints. Soft soldering is not recommended.
After the holding charge has been vented and before brazing, wrap a wet rag around the copper con-
nections before removing the caps to prevent internal component damage. A torch can be used to
remove the caps over the ends of the supply and return lines.
During brazing, the lines must be filled with flowing dry nitrogen 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.
6.5.2 Recommended Piping Size
Connect the main pipes between the Liebert XDR branch piping and the Liebert XDP or Liebert XDC
according to Table 1. Elbows and restrictions must be minimized to ensure good fluid flow.
See Table 1 below for recommended pipe sizes and Figure 3 for piping segment locations.
See Figure 14 for piping recommendations for hard-piping between the Liebert XDR and the header
system.
6.6 Hard-Piped Connection Sizes
The supply piping for the refrigeration circuit is 1/2" OD copper pipe. The return piping for the circuit
is 7/8" OD copper.
The Liebert XDR modules that are intended for hard-piping connections will have copper caps sol-
dered in place and a holding charge of nitrogen.
Figure 14 Piping location and connection sizes—modules with hard-piped connections
Table 1 Branch piping sizes for pumped refrigerant loop
Pipe Function Size / Equivalent Pipe Length
From Liebert XDR supply to supply line of
Liebert XDP/Liebert XDC
1/2" OD (0.430" ID) for lengths up to 10 feet (3m)
7/8" OD (0.545" ID) for lengths over 10 feet but less than 25 feet (3-7.6m)
From Liebert XDR return to return line of
Liebert XDP/Liebert XDC
7/8" OD (0.545" ID) for lengths up to 10 feet (3m)
1-1/8" OD (1.025" ID) for lengths over 10 but less than 25 feet (3-7.6m)
NOTE
To minimize the amount of pumped refrigerant required, do NOT oversize the piping.
5-7/8"
(149mm)
1-1/2"
(38mm)
2-1/8"
(54mm)
1-1/8"
(29mm)
6-1/2"
(165mm)
TOP VIEW
(Rear of Cabinet) Refrigerant
Supply Line Schrader Valve
23-1/2" (597mm)
Refrigerant
Return Line
1-5/16"
(33mm)