19EX

Centrifugal Liquid Chiller

50/60 Hz

600 to 2300 Nominal Tons (2110 to 8090 kW)

Carrier's 19EX Hermetic and Open Drive Centrifugal Liquid Chillers operate with environmentally safe HFC-134a. These chillers combine industrial quality with superior efficiency in a packaged design to minimize system costs. The Carrier 17/19EX chiller features:


Features/Benefits

The 19EX hermetic centrifugal liquid chiller features:

Single-piece factory package - The 19EX chiller is completely assembled in the factory and shipped in one piece to the jobsite. This allows each unit to be tested before delivery to the customer. It also ensures that every aspect of the unit meets stringent quality standards specified by Carrier. One piece shipment eliminates costly and time consuming field assembly.

Modular construction - The cooler, compressor, condenser, and economizer/storage vessel assemblies are completely bolted together, making the 19EX chiller ideally suited for replacement projects where ease of disassembly and re-assembly at the jobsite are essential.

Application flexibility - By providing a wide assortment of compressor and gear arrangements, the 19EX chiller is an efficient, quality package ideally suited for domestic chilled water, export chilled water, brine chilling, and ice making applications.

Hermetic Motor Design - A hermetic motor design in which the motor is sealed from the ma-chine room. Cooling is accomplished by spraying liquid refrigerant on the motor windings. This highly efficient motor cooling method uses smaller motors than air-cooled designs of the same capacity. Thus, hermetic motors require less in-rush current and are smaller and lighter than comparable air-cooled motors.

Lubrication system - This forced lubrication system consists of an electrically-driven oil pump, filter, heater, and refrigerant-cooled or water-cooled oil cooler. It provides an ad-equate supply of oil to the transmission gears and all bearing surfaces during start-up, operation, and coastdown. The electrically driven oil pump is supplied by a separate power line ensuring an adequate oil supply in the event of compressor power interruptions. A microprocessor-controlled oil heater prevents excessive absorption of refrigerant into the oil during compressor shutdown.

Variable inlet guide vanes - These vanes are connected with aircraft-quality cable and controlled by a precise electronic actuator. Chilled water temperature is maintained within ± .5 F (.3 C) of desired set point with-out surge, cavitation, or undue vibration. The vanes regulate inlet flow to provide high efficiency through a wide, stable operating range with-out hot gas bypass.

Double helical industrial type gears - Unlike single helical gears, double helical gears have a greater tooth-contact area which can transmit higher horsepower loads more smoothly. In addition, this design absorbs axial thrust loads that are generated in the transmission of power to ensure a long, dependable life for all components in the system.

Split-sleeve, steel back, babbitt-lined journal bearing - The 19EX chiller uses 2 steel back, babbit-lined bearings on both sides of the thrust bearing to form a ''fully supported'' internal shaft. The steel backing provides structural strength for the bearing, while the babbitt material provides a superior bearing surface. The split-sleeve design facilitates bearing inspection without shaft removal. This makes for a very solid rotating assembly which reduces heat, wear, vibration, and the possibility of shaft failure.

Tilting pad, self-leveling, babbitt-lined, Kingsbury-type thrust bearing - The Kingsbury-type thrust bearing employs an expanded equalized surface that faces a rotating disc on the shaft. This surface is comprised of 8 pads made from babbitt. Each pad is supported by plates which give the pads a self-aligning nature, allowing for field adjustments. During operation, the pads take on a wedge-shape formation. This formation ensures that the load-carrying surfaces of the bearing are separated by a relatively thick film of lubricant, pre-venting metal-to-metal contact. In case of accidental reverse shaft rotation, the pads on the thrust bearing can realign themselves and form a wedge-shape in the opposite direction, consequently reducing wear and increasing bearing life.

Large inspection opening - Each compressor is equipped with an access cover to facilitate bearing and gear inspection without compressor disassembly. This makes the 19EX chiller ideal for yearly inspections and preventive maintenance programs. Compressor run tested - Every compressor assembly is run-tested in accordance with stringent Carrier engineering requirements. These tests, performed prior to final machine assembly, ensure proper and reliable operation.

The heat exchangers feature:

Pressure-tested vessels - Each heat exchanger (water-side) is hydrostatically tested at 150% of design pressure. The entire machine assembly is pneumatically burst-tested at 125% of design pressure and then subjected to a standing vacuum test. This increases unit reliability and ensures safe machine operation.

ASME certified construction - ASME ''U'' stamp and nameplate on both the refrigerant and water-sides of the chiller for safety, reliability, and long life.

Marine waterboxes - The marine waterboxes, optional on both cooler and condenser, facilitate tube cleaning and eliminate the need to disassemble piping.

High-performance tubing - Heat exchanger tubes can be internally and externally enhanced for high efficiency. A wide range of alternate tube types and materials is available.

Double-grooved tube sheet holes - Tubing is rolled and expanded into double grooved tube sheets to eliminate the possibility of leaks between the water and refrigerant system.

Closely-spaced intermediate support sheets - Tubes in the cooler and condenser are supported by closely-spaced intermediate support sheets which prevent tubes from sagging and vibrating.

Tube expansion at intermediate support sheets - Because of the volatile environment in the cooler heat exchanger, tubes are expanded into each intermediate support sheet, pre-venting unwanted tube movement and vibration.

Condenser impingement baffle - This feature prevents direct impingement of high velocity compressor discharge gas onto the condenser tubes. The baffle eliminates the related vibration and wear of the tubes and distributes the refrigerant flow evenly over the length of the vessel for im-proved efficiency.

Flash subcooler - The flash sub-cooler, located in the bottom of the condenser, brings warm condensed refrigerant into contact with the inlet (coldest) water tubes. This subcools the liquid to a temperature less than its condensing temperature. Therefore, the overall refrigeration cycle efficiency is increased, resulting in lower power consumption.

The flash economizer/storage vessel features:

Integrated economizer/storage vessel with pumpout unit - This system is self-contained, easy to operate, and more cost effective than remote storage options. As a self-contained unit, the 19EX chiller can be applied to applications that incorporate more than one type of refrigerant, without the cost penalty of requiring additional remote storage systems. Additionally, the optional pumpout compressor meets EPA's vacuum level requirements that man-date minimizing refrigerant emissions during service.

Interstage flash economizer - The liquid refrigerant leaving the con-denser passes through 2 pressure reducing devices in the economizer/ storage vessel before reaching the cooler. After going through the first device, some of the liquid flashes because of the sudden drop in pressure. It is drawn off to the inlet of the compressor second stage, reducing the first stage weight flow and horse-power. As a result, the economizer increases refrigeration effect and cycle efficiency.

Ball-type float valves - These valves provide precise refrigerant metering at any load. As a result, optimal refrigerant levels can be maintained in the condenser and cooler to achieve the greatest efficiency with-out gas bypass or flooding.

Bolt-on covers - These covers allow access to the float valves to facilitate inspection.

Storage tank - This tank is sized so that the entire refrigerant charge occupies no more than 90% of the tank volume at 90 F (32 C). This feature reduces service worktime, minimizes downtime, eliminates the additional space required for a separate tank, and eliminates the need for costly field-erected transfer piping.

Isolating valves - These valves isolate the integrated economizer/storage vessel from the condenser, cooler, and compressor during pumpout and servicing.

Microprocessor controls feature:

Direct digital Product Integrated Controls (PIC) - The PIC provides unmatched flexibility and functionality. Each unit integrates directly with the Carrier Comfort Network (CCN) providing a system solution to controls applications.

Local Interface Device (LID) - This device, configured to display in either English or metric units, provides unparalleled ease of human inter-face. A 16-line by 40-character LCD (liquid crystal display) features 4, menu-specific, softkeys. The default display offers ''all in one glance'' access to key chiller operating data, simplifying machine-user interface.

Optional modules - These modules offer control expandability by allowing chilled water reset and de-mand limit set points to be controlled from remote sources. Optional temperature sensors can also be connected and monitored by these modules.

Modular pull-out/plug-in design - Plug design reduces wiring requirements for easy installation.

Low-voltage design - The Class 2 control center design provides the ultimate assurance of personal safety and control integrity.

Over 100 PIC monitoring functions and conditions - PIC displays over 125 operating, state, and diagnostic messages for improved user interface.

Battery backup - Battery backup provides protection during power failures and eliminates time consuming control reconfiguration.

Extensive service menu - The service menu can be password-protected to prevent unauthorized access. Built-in diagnostic capabilities aid troubleshooting and recommend proper corrective action for pre-set alarms resulting in greater uptime. The control test allows the user to confirm operation of inputs and out-puts for increased confidence.

Automatic capacity override - This function unloads the compressor whenever key safety limits are approached, increasing unit life.

Encapsulated circuit board - Designed and built in-house, each board must meet Carrier's stringent quality standards resulting in superior reliability compared to open board designs.