Indoor Air Cooled Centrifugal Fan Condensing Unit Installation. Emerson Liebert Prop Fan Condensing Unit

Site Preparation and Installation

2.5

Indoor Air Cooled Centrifugal Fan Condensing Unit Installation

2.5.1

Location Considerations

The centrifugal fan air cooled condensing unit may be located above the dropped ceiling or any remote indoor area. If noise is of concern, the condensing unit should be located away from personnel. Normal operating sound may be objectionable if the condensing unit is placed near quiet work areas.

To mount the unit in the ceiling, refer to 2.4 - Installing the Ceiling Units.

2.5.2

Electrical Connections

Refer to 2.4.4 - Electrical Connections for general wiring requirements and cautions. Refer to elec-

trical schematic when making connections. Refer to unit serial tag for full load amp and wire size amp ratings.

Power Connections

The condensing unit requires its own power source and earth ground, with a disconnect switch to isolate the unit for maintenance.

NOTE

Refer to serial tag for full load amp and wire size amp ratings

Control Connections

Field-supplied control wires must be connected between the evaporator and the condensing unit (See

Figure 6 and Figure 9) and the electrical schematic on the units for more details.) Three (3) wires

are required between the evaporator and condensing unit. A fourth wire is required on systems with hot gas bypass.

2.5.3

Piping Connections

Details for Refrigerant (R-22) Loop piping are in 2.4.3 - Piping Connections and Coolant

Requirements.

2.5.4

Ducting

Fan operation is designed for 3300 CFM (560 CMH) at 0.5" external static pressure.

General Considerations

Use flexible ductwork or nonflammable cloth collars to attach ductwork to the unit and to control vibration transmission to the building. Attach the ductwork to the unit using the flanges provided.

Locate the unit and ductwork so that the discharge air does not short circuit to the return air inlet.

Ductwork that runs through a conditioned space or is exposed to areas where condensation may occur must be insulated. Ductwork should be suspended using flexible hangers. Ductwork should not be fastened directly to the building structure.

For multiple unit installations, space the units so that the hot condensing unit exhaust air is not directed toward the air inlet of an adjacent unit.

Considerations for Specific Applications

In applications where the ceiling plenum is used as the heat rejection domain, the discharge air must be directed away from the condensing unit air inlet and a screen must be added to the end of the discharge duct to protect service personnel. Locate the air discharge a minimum of 4 feet from an adjacent wall. Failure to do so may result in reduced air flow and poor system performance.

If the condensing unit draws air from the outside of the building, rain hoods must be installed. Hood intake dimensions should be the same as the condensing unit duct dimensions. In addition, install a triple layer bird screen over rain hood openings to eliminate the possibility of insects, birds, water or debris entering the unit. Avoid directing the hot exhaust air toward adjacent doors or windows.

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Site Preparation and Installation

Figure 8 Indoor air cooled centrifugal condensing unit dimensions and pipe connections

54 "

(1371.6mm)

CABINET

DIMENSION

1 5/8 "

(41.1mm)

48 "

(1219.2mm)

32 "

(812.8mm)

CABINET

DIMENSION

15 3/4 "

(400mm)

Customer supplied threaded rods for module support from ceiling

(typ. 4)

8 15/16 "

(227mm)

3 3/8 "

(85.7mm)

21 1/4 "

(539.8mm)

14 1/2 "

(368.3mm)

24 "

(610mm)

CABINET

DIMENSION

1 3/4 "

(44.5mm)

33 5/8 "

(854.1mm)

THREADED ROD

CENTERS

NOTE: Unit is spaced evenly in

reference to threaded

rod centers.

1/2" (12.7mm) dia. holes for threaded rods (typ. 2 each end)

51 13/16 "

(1316mm)

THREADED ROD

CENTERS

7/8" (22.2mm) & 1 1/8" (28.6mm) dia. knockouts electrical entrance for high voltage connection (Single Point Power Kit).

Single Point Power Kit connection to Evaporator.

Air Inlet

Liquid Line male quick connect location

Suction Line male quick connect location.

7/8" (22.2mm) dia. knockout electrical entrance for alternate control panel low voltage routing.

Hanger Bracket voltage connection.

7/8" (22.2mm) dia. electrical entrance for low voltage connection.

Air

Outlet

Shaded area indicates a recommended clearance of

30" (762mm) for component access and removal.

7/8" (22.2mm) & 1 1/8" (28.6mm) dia. knockouts electrical entrance for high

DPN000225_Rev0

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Figure 9 Indoor air cooled centrifugal condenser electrical connections

Field Supplied Unit Disconnect

Switch when Factory Unit

Disconnect Switch is not

Supplied

Site Preparation and Installation

Electric Service not by Liebert

Removable

Access Panels

Connection Terminal for Field Supplied

Earth Grounding Wire

Optional Factory Installed

Disconnect Switch

Line Voltage Electric Power

Supply Conduit Voltage

Field Supplied 24V NEC Class 2

Wiring Between Condensing

Unit and Fan/Coil Unit

Low Voltage Electric Power

Supply Conduit Entrance

NOTES:

1. Refer to specification sheet for full load amp. and wire size amp. ratings.

2. Control voltage wiring must be a minimum of 16 GA (1.6mm) for up to 75’ (23m) or not

to exceed 1 volt drop in control line.

Heat Rejection Connection. Field supplied

24V NEC Class 2 wiring. See Note 2. Wire connections from evaporator module:

1. 24V GND

2. 24V Supply

3. High Pressure Alarm (OPT)

4. Hot Gas Bypass Connection

(only on units with Hot Gas Bypass)

DPN000226_Rev0

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