Emerson Liebert XDR - Manual (Page 21)

Piping
15
Figure 13 Typical Liebert XDR piping—non-interlaced connection
6.3 Connection Methods and Points
Refer to site specific drawings for general locations of the piping connections. For Liebert XDR con-
nection locations, refer also to Figures 14, 17 and 21.
The assembly and connection means used for piping in the Liebert XD system are the same as those
used in conventional refrigeration systems. Observe all standard practices during installation and
startup to prevent damage and contamination. All piping must be ASTM Type ACR copper.
The Liebert XDR has supply and return piping access on the top of each module. Supply piping con-
nection is 1/2" OD copper pipe, and return piping connection is 7/8" OD copper. The hard-piped Lie-
bert XDR has a low-pressure nitrogen holding charge.
Both supply and return couplings may be supplied with optional one-shot couplings. These couplings
contain pressurized R-134a refrigerant inside the Liebert XDR.
For Liebert XDRs with removable couplings, the supply piping connection is 1/2" OD and the return
piping connection is 7/8" OD. Both the Liebert XDR and the Liebert XD Flex Pipe with removable cou-
plings have a low-pressure nitrogen holding charge.
6.4 Insulation
To minimize the possibility of condensation, insulate all piping between the Liebert XDR and the Lie-
bert XDP or Liebert XDC.
6.5 Venting the Holding Charge for Hard-Piped or Removable Liebert XD Flex Pipe
Couplings
The Liebert XDR in either hard-piped configuration or with removable couplings is shipped with a
low-pressure holding charge (about 30 psi) of nitrogen to prevent oxidation and moisture. This must be
vented from the refrigeration circuit before removing the copper cap.
To vent the holding charge:
1. Find the Schrader valve that retains the nitrogen holding charge in the Liebert XDR. The valve is
inside the rear door, on the supply line (see Figure 14 for hard-piped connections and Figure 22
for removable couplings).
2. Vent the holding charge in the circuit by depressing the pin in the Schrader valve on the supply
line.
3. Replace and secure the cap on the Schrader valve that was opened.
NOTE
This procedure is for modules with hard-piped or removable couplings ONLY. Do not vent a
pre-charged Liebert XDR or pre-charged Liebert XD Flex Piping.
TOP VIEW
Return
Supply
Liebert XDP/
Liebert XDC A
Liebert XDR A Liebert XDR A Liebert XDR A Liebert XDR A
DRAWING IS
NOT TO SCALE