Vertiv Liebert PCW - General Description; Single Chilled Water Circuit - L- C Versions; Double Chilled Water Circuit - X- R Versions

1Liebert PCW - UM - 273895 - 04.10.2018
1 - General Description
The Liebert
®
PCW is a full- featured precision air conditioner in-
tended for data centers, network closets, technological rooms (lab-
oratories, metrological rooms, museums), new and existing con-
structions, raised and non- raised oors, moderate to high density
heat loads, also in combination with cold aisle containments (up to
10 kW/Rack). It provides all the necessary functions of a standard
precision air conditioner, including cooling, heating, humidication,
dehumidication, air ltration, condensate management, tempera-
ture control, alarm functions and data communications. Liebert
®
PCW is designed on modular concept. Every Liebert
®
PCWunit is
composed (at least) of a coil section and a base or top fan section
with fan(s) installed on it.
The Liebert
®
PCW Standard Height Unit is supplied as a single unit
(height 1970mm), where coil and fan sections are connected.
The Liebert
®
PCW Extended Height is supplied in two modules,
the Coil Module (coil section)and the Fan Module (fan section). The
two modules should be connected on the eld (see chap. 3 Instal-
lation) (total height 2570 mm). The Fan Module is called Fan Base
Module when placed on the raised oor, Fan Base Frame when
installed in the raised oor, Fan Top Plenum when installed on the
top of the cooling unit.
The units are available in the four congurations shown below.
Upow
Downow Up
Downow Down
Downow Frontal
1.1 - Single chilled water circuit - L- C versions
The unit is provided with a 2-way or 3-way modulating valve (1),
complete with incremental
motor for the control of water
ow to the coil (2); the open-
ing or closing signals, gener-
ated by the electronic control-
ler, manage the valve
actuator movement in order
to maintain the desired condi-
tions.
The room air is cooled pass-
ing through the coil (2) (air/
water heat exchanger),
moved by the motor fan (3).
The iCOM Control (or CDL
Graphic Display / opt.) con-
trols all parameters.
It is possible to adjust, for in-
stance: set points, proportional or proportional+integral tempera-
ture, integrating factor and valve characteristics.
It is also possible to manually adjust the valve with a suitable
wrench.
Chilled Water
(from Customer)
1
2
3
1.2 - Double chilled water circuit - X- R versions
The unit is equipped with two independent chilled water circuits in
cascade to one single coil, each cir-
cuit is equipped with 3-way/2-way
control valve (1), complete with incre-
mental motors for the water ow con-
trol of each circuit.
These units can be connected to
chilled water circuits coming from
two independent sources. In case
the rst circuit failure, the second one
can substitute the need for cooling
capacity and provide the necessary
back up.
The circuit 1 (valve located on the left
side, looking from the unit’s front) is
before the circuit 2 (valve located on
the right side, looking from the unit’s
front) on the air-stream.
1
1
Chilled Water
(from Customer)
1
1
2
3