Piping
19
5.8 Connecting Liebert XD Flex Pipes to Liebert XDH Modules
1. Remove the caps on the supply and return lines on the top of the Liebert XDH.
2. Lubricate the threads, diaphragm and O-ring with one or two drops of mineral oil.
3. Connect the line-set coupling finger-tight.
4. Make sure the Schrader valve is properly oriented; refer to the label on the top of the Liebert
XDH.
5. Hold the backup hex nut with a wrench while tightening the swivel nut.
6. Tighten the swivel nut on the female coupling until it is seated or a definite resistance is felt.
7. Once a definite bottoming resistance is felt (as in metal to metal), place a mark lengthwise from
the swivel nut to the backup hex and tighten the swivel nut on the female coupling an additional
1/4 turn.
8. Tighten the supply fittings to 35-45ft/lb (47-61Nm).
9. Tighten the return fittings to 55-65ft/lb (74-88Nm).
10. Mark the female and male coupler with for future reference.

5.8.1 Header System

The Liebert XDH module system with optional flexible piping requires use of the Liebert XD prefabri-
cated piping assembly. The prefabricated piping is compatible with the Liebert XD Flex Pipe required
to attach to the Liebert XDH modules. For the details on piping connection locations, see Figure 16.
For additional information, refer to the Liebert X-treme Density System Design Manual, SL-16655.
5.9 Connecting a Liebert XDH with Liebert XD Flex Pipe to an Operational Liebert XD System

Tools Required

• Two adjustable wrenches, with a maximum adjustment size of 2-1/2 inches
• S crewdriver, Phillips or blade type
1. Determine the port location of the supply and return piping overhead
2. Make sure the service valve for each port is closed
3. Remove cap for only the required ports. Do not remove caps from the unused ports.
4. Once Step 3 has been completed, remove the pipe plugs that are supplied on the Liebert XD Flex
Pipe.
5. Use system refrigerant to lubricate the face of the male coupling half, including the poppet valve
face and the stainless steel delta ring.
!
CAUTION
Risk of high pressure refrigerant discharge. May cause injury and air pollution.
Do not disconnect one-shot refrigerant connections after they have been connected.
Disconnection will release pressurized R-134a refrigerant from the Liebert XDH.
NOTE
Before connecting the Liebert XDH with Liebert XD Flex Pipe to the prefabricated piping
mains, check the entire system for leaks.
Check the holding charge in the Liebert XDH to ensure that the unit has no leaks.
Read all instructions before beginning installation.
NOTE
This operation requires two people.