Piping and Filling with Refrigerant: R-134a and R-407c Circuits
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2.0 PIPING AND FILLING WITH REFRIGERANT: R-134A AND R-407C CIRCUITS2.1 European Union Fluorinated Greenhouse Gas Requirements
Stationary air conditioning, refrigeration, heat pump equipments and stationary fire protection sys-
tems in the European Community market and operating with fluorinated greenhouse gases (f-gas),
such as R407C, R134a, R410A, must comply with the F-Gas Regulation: (EC) No. 842/2006 (F-gas).
The regulation prohibits, among other actions, venting fluorinated greenhouse gases to the atmo-
sphere.
The F-Gas Regulation requires operators to use use all measures that are technically feasible and do
not entail disproportionate cost to prevent leakage of these gases, to test for leakage regularly and to
recover f-gas before disposing of equipment, as well as during service and maintenance.
Refer to the full regulation for additional details.
2.2 Recommended Pipe Size
Connect the main pipes between the Liebert XDC and the Liebert XD cooling modules according to
site specific documentation and the configuration guide for the Liebert XD system.
Elbows and restrictions shall be minimized for proper operation.
2.3 Liebert XDC Interconnection With Liebert XD Cooling Module
All piping must be ASTM (American Society for Testing and Materials) Type “L” copper pipe.
The Liebert XDC may be connected to Liebert XD cooling modules with either Liebert’s XD prefabri-
cated piping assembly or with rigid, off-the-shelf piping. In either setup, piping for the Liebert XD
system is arranged in a manner similar to piping for a chilled water system. Liebert XD cooling mod-
ules are connected in parallel between main return and supply pipes going to and from the Liebert
XDP/Liebert XDC. Figure 19 represents a typical configuration. For piping details, refer to Liebert’s
XD System Design Manual, SL-16655. The guidelines provided for pipe size must be strictly
followed. Failure to size the main lines and connection lines adequately may result in
reduced cooling capacity. The critical aspects of pipe sizing are related to coolant volume and pres-
sure drop. Both must be minimized.
NOTE
Follow all local codes on maximum length and size of refrigerant lines.
Table 4 Supply, return pipe sizes for Liebert XD refrigerant loop
Pipe Function Size/Equivalent Pipe Length
Liebert XDC supply line, from Liebert XDC
supply to farthest Liebert XD cooling module
1-1/8" OD (1.025" ID) for lengths up to 60 feet
1-3/8" OD (1.265" ID) for lengths over 60 but less than 175 feet
Liebert XDC return line, from farthest cooling
module to Liebert XDC return
2-1/8" OD (1.985" ID) for lengths up to 60 feet
2-5/8" OD (2.465" ID) for lengths over 60 but less than 175 feet
From any model Liebert XDO/Liebert XDH
supply to supply line of Liebert XDC
1/2" OD (0.430" ID) for lengths up to 10 feet
7/8" OD (0.785" ID) for lengths over 10 but less than 25 feet
From any model Liebert XDO/Liebert XDH
return to return line of Liebert XDC
7/8" OD (0.785" ID) for lengths up to 10 feet
1-1/8" OD (1.025" ID) for lengths over 10 but less than 25 feet
From any model Liebert XDV/Liebert XDCF
supply to supply line of Liebert XDC
1/2" OD (0.430" ID) for lengths up to 10 feet
5/8" OD (0.545" ID) for lengths over 10 but less than 35
From any model Liebert XDV/Liebert XDCF
return to return line of Liebert XDC
5/8" OD (0.545" ID) for lengths up to 10 feet
7/8" OD (0.785" ID) for lengths over 10 but less than 35 feet