Vertiv Liebert XD Series, System Design Manual

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6.1.3 Condenser Coil
Liebert-manufactured coils are constructed of copper tubes in a staggered tube pattern. Tubes are
expanded into continuous, corrugated aluminum fins. The fins have full-depth fin collars completely
covering the copper tubes, which are connected to heavy wall Type “L” headers. Inlet coil connector tubes
pass through relieved holes in the tube sheet for maximum resistance to piping strain and vibration. Coils
are either single circuit or dual circuit, depending on the application. The hot-gas and liquid lines are
spun shut at the factory and include a factory-installed Schrader valve. Coils are factory leak-tested at a
minimum of 300 psig (2068kPag), dehydrated, then filled and sealed with a nitrogen holding charge for
shipment.
6.1.4 Housing
The condenser housing is fabricated from bright aluminum sheet and divided into individual fan sections
by full width baffles. Structural support members, including coil support frame, motor and drive support,
are galvanized steel for strength and corrosion resistance. Aluminum legs are provided for mounting unit
for vertical discharge and have rigging holes for hoisting the unit into position. The unit's electrical panel
is inside an integral NEMA 3R weatherproof section of the housing.
6.1.5 Propeller Fan
Aluminum propeller fan blades are secured to a corrosion-protected steel hub. Fan guards are heavy
gauge, close-meshed steel wire with corrosion resistant PVC finish rated to pass a 675-hour salt spray test.
Fans are secured to the fan motor shaft by a keyed hub and dual setscrews. Fan diameter is 26" (660mm)
or less. The fans are factory-balanced and run before shipment.
6.1.6 Fan Motor
The condenser's fan motor is a continuous air-over design equipped with rain shield and permanently
sealed bearing. Die-formed, galvanized steel supports are used for rigid mounting of the motor.
6.1.7 Electrical Controls
Electrical controls, overload protection devices and service connection terminals are factory-wired inside
the integral electrical panel section of the housing. A locking disconnect switch is factory-mounted and
wired to the electrical panel and controlled via an externally mounted locking door handle. An indoor unit
interlock circuit enables condenser operation whenever indoor unit compressors are active. Only supply
wiring and indoor unit interlock wiring are required at condenser installation.
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