Technical Specifications

System Description
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1.10 Liebert XDP—Pumping Unit
The Liebert XDP isolates the building’s chilled water circuit from the pumped refrigerant circuit. The
Liebert XDP circulates refrigerant to Liebert XD cooling modules while preventing condensation by
maintaining the refrigerant’s temperature above the room dew point at the sensors. The Liebert XDP
employs two sets (for redundancy) of remote sensors to determine the temperature and humidity in
the air and instantly adjusts refrigerant supply temperature to compensate for changing conditions.
The Liebert XDP uses the Liebert iCOM. This advanced control enables the user to monitor
essentially all aspects of the Liebert XD Precision Cooling system, from operating status to
maintenance.
1.10.1 Liebert XDP Minimum Load
The Liebert XDP’s minimum recommended operating load is 30% of system nominal capacity. For
example, a Liebert XDP160 60Hz system’s minimum load would be 48 kW. Loading below this value
can unfavorably affect system operation.
Figure 11 Liebert XDP
1.11 Liebert XD Piping
Liebert XD Piping is prefabricated distribution piping that is installed in anticipation of a growing
system. Liebert XD cooling modules are added as required and are quickly made operational with
flexible connection piping with threaded couplings. This unique system allows the room cooling
capacity to increase to more than 30kW per rack with no additional disruptive piping installation.
The flexible connection piping also allows the cooling modules to be re-positioned without
interruption in operation.