Vertiv Liebert XDU 060, Installer/User Manual

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6.5 Filling the System
The piping must be filled prior to operating the pumps to avoid damage to the pump and pump seals. The pump seals are
cooled and hydrodynamically lubricated by the system fluid.
Charging and filling is done through an expansion tank fill valve located inside of the unit. A 1/4-inch SEA flare Schrader
connection is provided inside of the rear door at the base of the unit. See Figure 6.3 below.
The fill valve will stop the flow of fill when the system pressure reaches the bladder pressure. The fill valve is also a check
valve to prevent water from leaving the system when the fluid source is turned off. The expansion tank contains a bladder
that is pre-charged to 12 psig and is ready for use without adjustment.
Bleeding the air from the system is accomplished through three 1/4-inch SEA connections on the top of the XDU. When
filling, bleed air from the coil bleed connection nearest the back of the unit first, until a steady stream of fluid is observed.
Bleed air from the remaining two connections as needed. See Figure 6.1 on page 28. Units piped from the top supply and
return connections will be bled from field provided connections at the highest point of the field piping system and not from
the two connections adjacent to the top connections.
It is recommended to perform a preliminary flush with clean potable water to flush the XDU unit, field piping, and hose set
prior to filling the unit for connection to the server load cabinet. This will prevent any install debris from plugging the small
passages within the servers.
Figure 6.3 Fill Valve Location
Vertiv | XDU™ Liquid to Air Heat Exchanger for Chip Cooling
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