Catalogue

6 CG-PRC017H-EN
Application Considerations
Certain application constraints should be considered when sizing, selecting and installingTrane
CGAM chillers. Unit and system reliability is often dependent upon proper and complete
compliance with these considerations.Where the application varies from the guidelines presented,
it should be reviewed with your localTrane account manager.
Note: The terms water and solution are used interchangeably in the following paragraphs.
Unit Sizing
Unit capacities are listed in the Performance Data section. Intentionally over-sizing a unit to assure
adequate capacity is not recommended. Erratic system operation and excessive compressor
cycling are often a direct result of an oversized chiller. In addition, an oversized unit is usually more
expensive to purchase, install, and operate. If over sizing is desired consider using two smaller
units.
Water Treatment
The use of untreated or improperly treated water in chillers may result in scaling, erosion,
corrosion, and algae or slime buildup.This will adversely affect heat transfer between the water
and system components. Proper water treatment must be determined locally and depends on the
type of system and local water characteristics.
Neither salt nor brackish water is recommend for use inTrane air-cooled CGAM chillers. Use of
either will lead to a shortened life.Trane encourages the employment of a qualified water treatment
specialist, familiar with local water conditions, to assist in the establishment of a proper water
treatment program.
Foreign matter in the chilled water system can also increase pressure drop and, consequently,
reduce water flow. For this reason it is important to thoroughly flush all water piping to the unit
before making the final piping connections to the unit.
The capacities give in the Performance Data section of this catalog are based on water with a
fouling factor of 0.0001°F·ft²·h/Btu (in accordance with AHRI 550/590). For capacities at other fouling
factors, see Performance Selection Software.
Effect of Altitude on Capacity
Chiller capacities given in the Performance Data section are based upon application at sea level.
At elevations substantially above sea level, the decreased air density will decrease condenser
capacity and, therefore, unit capacity and efficiency.
Ambient Limitations
Trane chillers are designed for year-round operation over a range of ambient temperatures.The air-
cooled model CGAM chiller will operate in ambient temperatures of 32°F to 125°F (0°C to 52°C) for
high ambient or 0°F to 125°F (-18°C to 52°C) for wide ambient. Operation down to 0°F requires the
use of variable speed fans to modulate and maintain system differential pressure.
The minimum ambient temperatures are based on still conditions (winds not exceeding five mph).
Greater wind velocities will result in a drop in head pressure, therefore increasing the minimum
starting and operating ambient temperature.The Adaptive Control™ microprocessor will attempt
to keep the chiller on-line when high or low ambient conditions exist, making every effort to avoid
nuisance trip-outs and provide the maximum allowable tonnage.