Technical Specifications

Designing a Liebert XD Solution
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Verify that the refrigerant volume of the Liebert XD system with the longest piping length is within
the allowable limit. If the allowable limit is exceeded, the Liebert XDP/Liebert XDC should be moved
closer to the cooling modules (refer to 3.22 - Liebert XD Refrigerant for limits and related details).
Another way to shorten the total pipe length is to reroute the pipe runs.
3.24 Chilled Water Piping
The Liebert XDP is offered only with a two-way chilled water control valve. Some applications may
require the use of a pressure activated bypass valve to prevent dead-heading of the chilled water
pump. This bypass valve must be specified by the engineer responsible for design of the chilled water
field piping system.
NOTICE
Risk of particles in chilled water. Can cause equipment damage and reduced cooling.
Failure to install a strainer in the supply line to the Liebert XDP can result in damage to the
unit’s heat exchanger.
Install a 20-40 mesh strainer on the chilled water supply to the Liebert XDP. The strainer is required
to prevent particles in the chilled water from entering the heat exchanger of the Liebert XDP. The
maximum distance of the strainer from the Liebert XDP is 10 feet (3m).
Table 20 Worksheet to calculate refrigerant charge
Components
Number of Units
or Piping Length Pounds Per Component Total
Total