Trane CG-PRC007-EN manual Low Ambient Operation, High Ambient Operation, Temperature Controller

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Application Considerations

AMBIENT LIMITATIONS

Trane chillers are designed for year- round applications in ambients from 0°F to 115°F. For operation below 0°F or above 115°F, contact the localTrane sales office. If hot gas bypass is used, operating ambients vary depending upon unit size (see the “General Data” section of this catalog).

1

Low Ambient Operation

Start-up and operation of Trane chillers at lower ambient temperatures require that sufficient head pressure be maintained for proper expansion valve operation.

Minimum operating ambient temperatures for standard unit selections and units with hot gas bypass are shown in the “General Data” section of this catalog.

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 temperatures.

Optional low ambient units use a electronic low ambient damper control (20-60 tons) or a variable speed fan motor (10-15 tons) arrangement to control condenser capacity by modulating condenser fans in response to refrigerant pressure.

2

High Ambient Operation

Maximum cataloged ambient temperature operation of a standard Trane chiller is 115°F. Operation at design ambients above 115°F can result in excessive head pressures. For operation above 115°F, contact your localTrane sales office.

CONTROLS

1

Temperature Controller

In order to provide stable system operation and to prevent excessive compressor cycling, the temperature control sensor in all 20-60 ton chillers is located in the supply (outlet) solution. The temperature sensor in all 10 and 15 ton chillers is located in the return (inlet) solution.This sensor cannot be relocated. Doing so would result in improper unit operation.

2 Anti-recycleTimer/Fixed-OffTimer

All IntelliPak air-cooled chillers come standard with Anti-recycle/Fixed Off Timers.This function prevents rapid cycling of the compressors due to low load conditions or short water loops.

3

Pumpdown

CGAF air-cooled chillers will pumpdown, if function is enabled, when a refrigerant circuit is turned off. All of the refrigerant is pumped into the condenser. A solenoid valve provides a positive shut off between the condenser and the evaporator, allowing little or no refrigerant migration to the evaporator during “off” periods.

4

Hot Gas Bypass

Hot gas bypass provides more stable leaving solution temperature control at light load conditions.The compressor runs continuously for a user-defined run time. Minimum starting and operating ambients with hot gas bypass are shown in the “General Data” section of this catalog.The hot gas bypass reduces the unit head pressure, thereby increasing the minimum operating ambient.

5

Loss of Flow Protection

Loss of flow may result in evaporator freeze up. Full chilled solution flow must be maintained through the evaporator while compressors are operating.

A flow switch used as a safety interlock is always recommended for CGA units.

The CGAF air-cooled chiller has a system which senses a loss of flow condition and shuts the unit down. A flow switch used as a safety interlock is required for CGAF units. A set of contacts is available for externally starting and stopping the pump.

WATERFLOW LIMITS

The minimum water flow rates are given in the “General Data” section of this catalog. Evaporator flow rates below the tabulated values will result in laminar flow causing scaling, stratification, freeze-up problems, and poor temperature control.

The maximum evaporator water flow rate is given in the “General Data” section. Flow rates exceeding those listed will result in excessive tube erosion and very high pressure drop across the evaporator.

Trane recommends that constant water flow be maintained at all times through the evaporator. Because the temperature controller strictly senses temperature, variable flow through the evaporator may result in loss of control and localized freezing or nuisance low temperature cutouts. Consult your local Trane sales engineer if your application requires varying flows.

TEMPERATURE LIMITS

1

Leaving SolutionTemperature range

The minimum leaving solution temperature set point is dependent on the number of capacity stages and the temperature difference across the evaporator.Water supply temperature set points less than these values result in suction temperatures at or below the freezing point of cold water.

A glycol solution is required for operation below the recommended minimum set points. Refer to the “Performance Adjustment Factors” section of this catalog to determine the minimum leaving chilled solution set

CG-PRC007-EN

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Contents Air-Cooled Liquid Chillers 10, 15Tons 20-60Tons IntroductionContents Benefits Features10-60Ton Flexibility 10-15Ton20-60Ton Standard FeaturesOther Standard Features Optional FeaturesTracer control points for IntelliPak Chillers Enhanced ControlsLowTorqueVariation Proven DesignThroughTesting and ResearchTrane 3-D Scroll Compressor Simple Design with 70% Fewer PartsUnit Location General SettingThe UnitIsolation and Sound Emission ServicingProvide Sufficient Unit-to-Unit Clearance Walled Enclosure InstallationsProvideVertical Clearance Provide Lateral ClearanceHigh Ambient Operation Temperature ControllerLeaving SolutionTemperature range Low Ambient OperationSeries Operation SupplyWaterTemperature DropExample CGAFC50 with 100 gpm. Minimum LoopVolume = Gallon Minimum LoopVolume20-60Ton Application Considerations10, 15Ton Given Selection Procedure20-60Tons Model Number Description10, 15Tons Table GD-1 General Data 10-60Ton Units General Data∆ T Performance Adjustment FactorsWater Drop Pressure Performance Adjustment Factors Performance Adjustment Factors Table PD-1 10 Ton CGA PerformanceData 60 HZ Full LoadTable PD-4 25Ton CGAF-C25 20-25TonTable PD-3 20Ton CGAF-C20 Table PD-6 40Ton CGAF-C40 30-40TonTable PD-5- 30Ton CGAF-C30 Table PD-8- 60Ton CGAF-C60 50-60TonTable PD-7- 50Ton CGAF-C50 Data 50 HZ 10-30TonTable PD-17- 60Ton CGAF-C60 40-60TonTable PD-15 40Ton CGAF-C40 Table PD-16 50Ton CGAF-C50Table PD-18 Part Load Data,ARI Points 10-60Tons Part LoadTable PD-18- Part Load Data,ARI Points 10-60Tons Table PD-22 25Ton CGAF-C25 Table PD-19 10Ton CGATable PD-20 15Ton CGA Table PD-21 20Ton CGAF-C20Table PD-26- 60Ton CGAF-C60 Table PD-24- 40Ton CGAF-C40Table PD-25- 50Ton CGAF-C50 Trane Integrated Comfort System Interface Required FeaturesInterface with Other Control Controls Systems10, 15Ton ControlsTon Operation Field Installed Head Pressure Control Accessory10, 15 Ton Customized Control Safety ControlsMonitoring and Diagnostics Controls 20-60 TonMain Menu of the Human Interface panel Standard Control Features20-60Ton Controls Interface Human Interface HI PanelOptional Control Features One binary output can be assigned to 5 binary outputs can be assigned4 analog outputs can be assigned to Table ED-1 Electrical Data Electrical 10-60Ton Data 60 HZLoad Definitions Table ED-2 Electrical Data Electrical 10-60Ton Data 50 HZFigure DD-1 CGA-120B Unit Dimensions Dimensional 10Ton DataFigure DD-2 CGA-180B Unit Dimensions Dimensional 15Ton DataFigure DD-3 CGAF-C20 Unit Dimensions Dimensional 20Ton DataFigure DD-4 CGAF-C25 Unit Dimensions Dimensional 25Ton DataFigure DD-5 CGAF-C30 Unit Dimensions Dimensional 30Ton DataFigure DD-6 CGAF-C40 Unit Dimensions Dimensional 40Ton DataFigure DD-7 CGAF-C50 Unit Dimensions Dimensional 50Ton DataFigure DD-8- CGAF-C60 Unit Dimensions Dimensional 60Ton DataTable W-3 Cgaf Unit Weights lbs WeightsTableW-1 Approximate CornerWeights lbs 10-Ton Unit TableW-2 Approximate CornerWeights lbs 15-Ton UnitMechanical 10-15TonSpecifications Mechanical 20-60TonSpecifications Unit Mounted Disconnect Zone Sensor Chilled Solution ResetIce Building Compressor Current Sensing CSMCG-PRC007-EN Trane

CG-PRC007-EN specifications

The Trane CG-PRC007-EN is a robust product within the Trane line of commercial rooftop units, designed to meet the heating and cooling needs of various commercial applications. This unit showcases advanced technologies and features aimed to enhance efficiency, reliability, and user comfort.

One of the standout characteristics of the CG-PRC007-EN is its commitment to energy efficiency. The unit incorporates high-efficiency compressors and a variable-speed fan motor, ensuring that the system can adjust its operation based on the demand, thus optimizing energy consumption. This is particularly advantageous in commercial settings, where climate control requirements can fluctuate throughout the day.

Additionally, the unit is engineered with a smart control system that allows for easy integration with building management systems. This feature enables real-time monitoring and adjustments, helping facility managers maintain optimal comfort levels while also minimizing operational costs. Users are able to access performance data and system diagnostics remotely, promoting proactive maintenance and reducing downtime.

Durability and longevity are critical factors for commercial HVAC systems, and the CG-PRC007-EN is designed with this in mind. The unit features a corrosion-resistant cabinet and components that withstand harsh weather conditions, ensuring reliability in outdoor installations. Its robust construction helps mitigate noise levels, resulting in a quieter operation that is ideal for noise-sensitive environments.

Another key technology within this unit is its advanced airflow management system. This system is designed to provide consistent airflow, enhancing indoor air quality and ensuring that every corner of the space benefits from appropriate heating or cooling. The CG-PRC007-EN also offers a variety of customization options for air filters, ensuring that the specific needs of each application are met.

Furthermore, the unit is compliant with the latest environmental regulations, including those set forth by the EPA. It utilizes eco-friendly refrigerants that minimize environmental impact without sacrificing performance. This makes the CG-PRC007-EN an excellent choice for companies committed to sustainability and energy efficiency.

In summary, the Trane CG-PRC007-EN combines innovative technology, energy efficiency, and reliability, making it an ideal solution for commercial heating and cooling needs. Its advanced features, durability, and eco-friendly design position it as a leader in the commercial rooftop unit market.
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