Installation Of Unit Pipes - Emerson Liebert DM Chilled Water Series User Manual

Chapter 2 Mechanical Installation
11

2.5 Installation of unit pipes

The pipes to be connected include:
1. Drainage pipe of the unit:
2. Inlet and outlet pipes of chilled water.
Connection of the drainage pipe
The external diameter of the condensed water drainage pipe of the unit heat exchanger is 19mm. The condensed
water drainage pipe is fixed to the right side of the unit base. It shall be connected to a water pipe with the inner
diameter of 19 mm and fixed with pipe hoop.
Note
1. A Φ19 pipe hoop is delivered as an option for connecting the drainage pipe.
Connection of chilled water inlet and outlet pipes
The chilled water inlet and outlet pipes are connected to the chilled water unit through threaded joint, as shown in Fig.
2-7.The inlet and outlet pipes should be connected according to labels on the unit. Please do not reverse the
connection. The chilled water inlet and outlet pipes can be connected through the bottom plate or the side plate. For
the pipe inlet and outlet position, please refer to Fig. 2-3 and Fig. 2-4. The chilled water inlet and outlet pipes should
have soft connector at the unit connections. The chilled water inlet pipes should be equipped with the water filter with
over 60 meshes to facilitate the clearance of impurities in the pipes. The chilled water inlet and outlet pipes need to be
equipped with several isolating valves, which can cut off water sources during the period of maintenance. One of the
isolating valves can be balance valve. Chilled water system with a balance valve would be more efficient and more
accurate in controlling water distribution. For detailed distribution, please refer to Fig. 2-2.Water pressure should be
able to overcome the water pressure drop caused by all the components of water system. Considering the possibility
that water pressure drop would increase due to incrustant and impurities resulted from long-time running of the system.
Therefore, when choosing the head components (e.g. pump), we should consider making 20% ~ 25% redundancy.
The weight of water pipes connected with the unit should not be assumed by the unit. The chilled water inlet and outlet
pipes must be kept warm. Table 2-2 shows the connecting dimensions of chilled water inlet and outlet pipes of various
units.
Note
Be careful when connecting the chilled water inlet and outlet pipes. Before the operation, please read carefully the
following precautions:
1. Remove the dust shield.
2. Wipe the connecting base and threaded surface carefully with clean cloth.
3. Wind hemp thread or Teflon tape evenly on the threaded surface.
4. Tighten the threaded joint, ensuring accurate alignment of the threads.
5. Draw a vertical line from the male connector to the female connector with a marker.
6. Verify the sealing status by filling it with nitrogen or water. If any leakage is found, tighten it immediately or reconnect
the joint.
User Manual of Liebert_DM Chilled Water Series Cooling Unit