Mechanical (20–60Ton)Specifications

GENERAL

All chillers are factory run-tested to confirm proper operation. Units are checked on a computer-based test stand at typical ambient and water conditions and control operation is monitored. Units ship with a full operating charge of refrigerant and oil.

Units are constructed of 14-gauge welded galvanized steel frame with 14 and 16-gauge galvanized steel panels and access doors. Unit surface is phosphatized and finished with an air- dry paint.This air-dry paint finish is durable enough to withstand a 1000- consecutive-hour salt spray application in accordance with standard ASTM B117.

Evaporator

Braze plate construction designed to withstand a waterside working pressure of 300 psig and a refrigerant side working pressure of 225 psig. It has one water pass. Etched foil heaters protect the evaporator to an ambient of -20°F.

Flow Switch

This factory supplied item indicates the loss of evaporator flow and ships with the unit for field installation.

Strainer (with installation hardware)

The strainer is required to prevent collection of particles within the evaporator.

Condenser

Air-cooled condenser coils have configurated aluminum fins mechanically bonded to seamless copper tubing and integral subcooling circuits. Condensers are factory leak- tested with air underwater at 425 psig air pressure.

Direct-drive vertical discharge condenser fans are statically and dynamically balanced.Three-phase condenser fan motors with permanently lubricated ball bearings and three-phase thermal overload protection. Optional low ambient units start and operate to 0°F with electronic damper assemblies for head pressure control.

Decorative grilles provide protection from exterior damage to coil surface and

other interior unit components. Grilles are factory mounted, louvered, galvanized steel mesh panels finished with an air-dry paint. Grilles will cover all open ends of units.

Compressors

Trane 3-D Scroll compressors have simple mechanical design with only three major moving parts. Scroll type compression provides inherently low vibration.The 3-D Scroll provides a completely enclosed compression chamber which leads to increased efficiency. Exhaustive testing on the 3-D Scroll, including start up with the shell full of liquid, has proven that slugging does not fail involutes. Direct-drive, 3600 rpm, suction gas-cooled hermetic motor. Trane 3-D Scroll compressor includes centrifugal oil pump, oil level sight glass and oil charging valve. Each compressor shall have crankcase heaters installed, properly sized to minimize the amount of liquid refrigerant present in the oil sump during off cycles.

Refrigerant Circuits and Capacity Modulation

Twenty to 30-ton sizes have a single refrigerant circuit. Forty to 60-ton sizes have dual refrigerant circuits. Each refrigerant circuit has twoTrane 3-D Scroll compressors, piped in parallel, with a passive oil management system. Passive oil management system maintains proper oil levels within compressors and has no moving parts. Each refrigerant circuit includes a liquid line solenoid valve, filter drier, liquid line sight glass with moisture indicator, thermostatic expansion valve, and service valves (liquid and discharge). Capacity modulation is achieved by turning compressors on and off.Twenty to 30-ton sizes have two capacity stages. Forty, 50 and 60-ton sizes have four capacity stages.The standard leaving chilled water temperature range is 40°F to 50°F. Options are available for leaving chilled solution temperature ranges from 20° to 29°F, 30° to 39°F, and 51° to 65°F.

Unit Controls

Compressor contactors and unit controls are in a weather tight enclosure with knockouts for jobsite installed wiring.The

unit controller shall be suitable to control leaving chilled solution temperature for comfort or process applications, automatic compressor sequencing, condenser fan sequencing, load limiting and anti-recycle functions. Failure protections include loss of chilled solution flow, chiller freeze protection, chilled solution flow interlock, head pressure control, pump down control, low ambient start, hot start control, and low ambient lockout. Leaving and entering solution temperature sensor is factory installed. Controls include auto/stop switch, a leaving water temperature set point adjustment, a DeltaT adjustment viewable through the unit Human Interface digital display.

Unit Controller

DDC microprocessor controls shall be provided to control all unit functions.The control system shall be suitable to control comfort and process applications.The controls shall be factory-installed and mounted in the main control panel. All factory-installed controls shall be fully commissioned (run tested) at the factory.The unit shall have a Human Interface Panel with a 16 key keypad, a 2 line X 40 character clear English display as standard to provide the operator with full adjustment and display of control data functions.The unit controls shall be used as a stand-alone controller, or as part of a building management system involving multiple units.

1

The unit shall be equipped with a complete microprocessor control system.This system shall consist of temperature and pressure (thermistor and transducer) sensors, printed circuit boards (modules), and a unit mounted Human Interface Panel. Modules (boards) shall be individually replaceable for ease of service. All microprocessors, boards and sensors shall be factory mounted, wired and tested.

The microprocessor boards shall be stand-alone DDC controls not dependent on communications with an on-site PC or a Building Management Network.The microprocessors shall be equipped with onboard diagnostics, indicating that all

CG-PRC007-EN

49

Page 49
Image 49
Trane CG-PRC007-EN manual Mechanical 20-60TonSpecifications

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.