Vertiv Liebert PEX+ Series, User Manual, Page: 44 / 109

Vertiv | Liebert PEX+Chilled Water | User Manual 34
Installation
2.4.9. Chilled Water Inlet and Outlet Piping Connection
• The chilled water supply and return pipes are connected with the Air Handling Unit (AHU) by threaded
connector (optional flanges or copper brazing mode), as shown in Figure 2-24 and Figure 2-25 . The supply
and return pipes should be brazed according to the labels on the unit. Do not reverse the connection. Chilled
water supply and return pipes can be connected through the base pallet or the side panel. The chilled water
supply pipes should be equipped with the water filter with over 60 meshes to facilitate the clearance of
impurities in the pipes.
• The chilled water supply and return pipes need to be equipped with several isolation valves, which can cut off
water sources during maintenance. One of the isolation valves can be a balancing valve. Chilled water system
with a balancing valve would be more efficient and more accurate in controlling water distribution.
• Water pressure should be sufficient to overcome the water pressure drop caused by all the components of
the water system. Considering the possibility that water pressure drop would increase due to deposition or
impurities resulted from long-time running of the system. Therefore, when choosing the fluid recirculating
component (e.g. pump), we should consider making 20% to 25% redundancy. The weight of the water pipes
connected with the unit should not be assumed by the unit. The chilled water supply and return pipes must be
kept warm. Table 2-9 shows the connecting dimensions of chilled water supply and return pipes of
Liebert® PEX+ CW units.
No. Description No. Description
1 Water supply pipe 2 Water return pipe
Figure 2-24 Connection of Chilled Water Supply and Return Pipes (upflow units)