Trane CG-PRC007-EN 10, 15 Ton, Ton Operation, Field Installed Head Pressure Control Accessory

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Controls

(10, 15 Ton)

 

 

 

 

SEQUENCE OF UNIT OPERATION

Refer to the unit wiring schematic pasted to the inside of the control panel cover when reviewing the control sequence described below.

Refer to the legend on the previous page for an explanation of the abbreviations used in this sequence.

10-Ton Operation

With fused disconnect switch closed, power is supplied to the crankcase heaters and the 24-volt control circuit.

Starting the chilled water pump closes the CWPS auxiliary contacts and completes the flow switch.

When the water temperature rises above theWTT’s set point, its first stage switch closes, allowing power to pass through CWPS auxiliary contacts, the flow switch, the LTC, the ASCT1, the RR1 contacts, the LPC01, and the HPC01 to energize the CC1 coil.This starts compressor number one and the outdoor fan.

If compressor number one can’t satisfy the cooling demand,WTT’s 2nd stage switch closes, allowing power to pass through the CC1 auxiliary contacts, the DBC, the ASCT2, the RR2 contacts, the LPC02, and the HPC02 to energize the CC2 coil which starts compressor number two.

15-Ton Operation

With fused disconnect switch closed, power is supplied to the crankcase heaters, and the 24-volt control circuit.

Starting the chilled water pump closes the CWPS auxiliary contacts and completes the flow switch, allowing power to pass through the LTC to energize the CWFIR.

When the water temperature rises above theWTT’s set point, its first stage switch closes, allowing power to pass through the CWFIR contacts, the ASCT1, the RR1 contacts, the LPC01, and the HPC01 to energize the CC1 coil.This starts compressor number one and outdoor fan number one.

If compressor number one can’t satisfy the cooling demand,WTT’s second stage switch closes, allowing power to pass through the CWFIR contacts, the DBC, the ASCT2, the RR2 contacts, the LPC02, and the HPC02 to energize the CC2 coil. This starts compressor number two and outdoor fan number two.

LOW AMBIENT OPERATION

Field Installed Head Pressure Control Accessory

Standard units will operate in outdoor ambient temperatures down to the values shown in the “General Data” section of this catalog. This accessory will enable units to operate down to much lower temperature extremes (see “General Data” section of this catalog).

Head pressure control for CGA units is regulated by means of a field-installed head pressure accessory which varies condenser fan speed in relation to discharge pressure.

When discharge pressure is 270 psig or higher, the condenser fan runs at full speed. At pressures between 270 psig and 180 psig, the fan speed is adjusted (increased or decreased) in direct relation to the pressure, with minimum fan speed (10 percent of rated motor rpm) occurring when the pressure reaches 180 psig. At pressures below 180 psig, the fan will not run.When discharge pressure rises to 180 psig, the fan will start and run at the reduced speed. Fan speed will continue to increase, as the pressure increases, until full speed is reached at 270 psig.

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CG-PRC007-EN

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Contents Air-Cooled Liquid Chillers Introduction 10, 15Tons 20-60TonsContents Benefits Features10-60Ton 10-15Ton FlexibilityStandard Features Other Standard FeaturesOptional Features 20-60TonEnhanced Controls Tracer control points for IntelliPak ChillersProven DesignThroughTesting and Research Trane 3-D Scroll CompressorSimple Design with 70% Fewer Parts LowTorqueVariationSettingThe Unit Isolation and Sound EmissionServicing Unit Location GeneralWalled Enclosure Installations ProvideVertical ClearanceProvide Lateral Clearance Provide Sufficient Unit-to-Unit ClearanceTemperature Controller Leaving SolutionTemperature rangeLow Ambient Operation High Ambient OperationSupplyWaterTemperature Drop Example CGAFC50 with 100 gpm. Minimum LoopVolume =Gallon Minimum LoopVolume Series Operation20-60Ton Application Considerations10, 15Ton Selection Procedure Given20-60Tons Model Number Description10, 15Tons General Data Table GD-1 General Data 10-60Ton UnitsPerformance Adjustment Factors ∆ TWater Drop Pressure Performance Adjustment Factors Performance Adjustment Factors Performance Data 60 HZFull Load Table PD-1 10 Ton CGATable 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 10-30Ton Data 50 HZ40-60Ton Table PD-15 40Ton CGAF-C40Table PD-16 50Ton CGAF-C50 Table PD-17- 60Ton CGAF-C60Table PD-18 Part Load Data,ARI Points 10-60Tons Part LoadTable PD-18- Part Load Data,ARI Points 10-60Tons Table PD-19 10Ton CGA Table PD-20 15Ton CGATable PD-21 20Ton CGAF-C20 Table PD-22 25Ton CGAF-C25Table PD-26- 60Ton CGAF-C60 Table PD-24- 40Ton CGAF-C40Table PD-25- 50Ton CGAF-C50 Required Features Interface with Other ControlControls Systems Trane Integrated Comfort System InterfaceControls 10, 15TonTon Operation Field Installed Head Pressure Control Accessory10, 15 Ton Safety Controls Monitoring and DiagnosticsControls 20-60 Ton Customized ControlStandard Control Features 20-60Ton Controls InterfaceHuman Interface HI Panel Main Menu of the Human Interface 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 Electrical 10-60Ton Data 50 HZ Table ED-2 Electrical DataDimensional 10Ton Data Figure DD-1 CGA-120B Unit DimensionsDimensional 15Ton Data Figure DD-2 CGA-180B Unit DimensionsDimensional 20Ton Data Figure DD-3 CGAF-C20 Unit DimensionsDimensional 25Ton Data Figure DD-4 CGAF-C25 Unit DimensionsDimensional 30Ton Data Figure DD-5 CGAF-C30 Unit DimensionsDimensional 40Ton Data Figure DD-6 CGAF-C40 Unit DimensionsDimensional 50Ton Data Figure DD-7 CGAF-C50 Unit DimensionsDimensional 60Ton Data Figure DD-8- CGAF-C60 Unit DimensionsWeights TableW-1 Approximate CornerWeights lbs 10-Ton UnitTableW-2 Approximate CornerWeights lbs 15-Ton Unit Table W-3 Cgaf Unit Weights lbsMechanical 10-15TonSpecifications Mechanical 20-60TonSpecifications Zone Sensor Chilled Solution Reset Ice BuildingCompressor Current Sensing CSM Unit Mounted DisconnectCG-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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