Emerson Liebert Challenger ITR - Manual (Page 20)

Air-Cooled System—Standard and Optional Features
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7.3 Air-Cooled Split Systems—Standard Features
7.3.1 Centrifugal Fan, Condensing Unit
The centrifugal condensing unit’s copper-tube, aluminum-fin coil is equipped with low-temperature
controls to ensure year-round operation to -20°F (-29°C). The condensing unit is factory-wired,
charged and tested and is ready for final connections.
The centrifugal fan condensing unit includes scroll compressor, condenser coil, centrifugal blower
assembly, high-pressure switch and Liebert Lee-Temp head pressure control.
Condensing unit has hot gas bypass standard feature which bypasses hot gas around the compressor
directly to the suction side of the compressor to provide capacity control and reduce compressor
cycling. System includes liquid injection valve to maintain proper suction superheat.
Unit must be mounted indoors. Duct flanges are provided.
7.3.2 Propeller Fan Condensing Unit
The air-cooled condensing unit can be mounted on the roof or a ground level site. The condensing unit
housing is manufactured of galvanized steel with a powder coat finish. The copper-tube, aluminum-
fin coil is equipped with low temperature controls to assure year-round operation to -30°F (-34.4°C).
The condensing unit is completely factory-wired, charged and tested and is ready for final connec-
tions. (See illustration below)
The standard prop fan condensing unit includes scroll compressor, prop fan, high head pressure
switch, hot gas bypass and Liebert Lee-Temp head pressure control (for operation down to -30°F (-
39°C) ambient.)
Figure 6 Outdoor propeller fan condensing unit
7.3.3 Propeller Fan Condensing Unit Options
This unit is available in these optional configurations:
• 105°F (40°C) ambient for high ambient conditions.
• 95°F (35°C) ambient Quiet-Line for low noise level conditions below 58 dBa.
7.4 Air-Cooled Split Systems—Optional Features
Factory-installed, non-fused disconnect switch allows turning off the Challenger ITR for main-
tenance. Disconnect switch is available on indoor condensing units only.