Factory-Mounted Starter or Variable Fre- quency Drive (Optional) — The starter allows for the proper start and disconnect of electrical energy for the com- pressor-motor, oil pump, oil heater, and control panel.

Storage Vessel (Optional) — There are 2 sizes of storage vessels available. The vessels have double relief valves, a magnetically-coupleddial-type refrigerant level gage, a one-inch FPT drain valve, and a 1/2-in. male flare vapor con- nection for the pumpout unit.

NOTE: If a storage vessel is not used at the jobsite, factory- installed isolation valves on the chiller may be used to isolate the chiller charge in either the cooler or condenser. An optional pumpout system is used to transfer refrigerant from vessel to vessel.

REFRIGERATION CYCLE

The compressor continuously draws refrigerant vapor from the cooler at a rate set by the amount of guide vane opening or compressor speed (19XRV only). As the compressor suction reduces the pressure in the cooler, the remaining refrigerant boils at a fairly low temperature (typically 38 to 42 F [3 to 6 C]). The energy required for boiling is obtained from the wa- ter flowing through the cooler tubes. With heat energy re- moved, the water becomes cold enough to use in an air condi- tioning circuit or for process liquid cooling.

After taking heat from the water, the refrigerant vapor is compressed. Compression adds still more heat energy, and the

refrigerant is quite warm (typically 98 to 102 F [37 to 40 C]) when it is discharged from the compressor into the condenser.

Relatively cool (typically 65 to 90 F [18 to 32 C]) water flowing into the condenser tubes removes heat from the refrig- erant and the vapor condenses to liquid.

The liquid refrigerant passes through orifices into the FLASC (Flash Subcooler) chamber (Fig. 3). Since the FLASC chamber is at a lower pressure, part of the liquid refrigerant flashes to vapor, thereby cooling the remaining liquid. The FLASC vapor is recondensed on the tubes which are cooled by entering condenser water. The liquid drains into a float cham- ber between the FLASC chamber and cooler. Here a float valve forms a liquid seal to keep FLASC chamber vapor from enter- ing the cooler. When liquid refrigerant passes through the valve, some of it flashes to vapor in the reduced pressure on the cooler side. In flashing, it removes heat from the remaining liq- uid. The refrigerant is now at a temperature and pressure at which the cycle began.

MOTOR AND LUBRICATING OIL

COOLING CYCLE

The motor and the lubricating oil are cooled by liquid re- frigerant taken from the bottom of the condenser vessel (Fig. 3). Refrigerant flow is maintained by the pressure differ- ential that exists due to compressor operation. After the refrig- erant flows past an isolation valve, an in-line filter, and a sight glass/moisture indicator, the flow is split between the motor cooling and oil cooling systems.

Fig. 3 — Refrigerant Motor Cooling and Oil Cooling Cycles

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Carrier XRV, 19XR specifications Refrigeration Cycle, Motor and Lubricating OIL Cooling Cycle

19XR, XRV specifications

The Carrier 19XR and 19XRV chillers are sophisticated cooling solutions that represent the forefront of HVAC technology. Designed for large commercial and industrial applications, these chillers provide exceptional performance, energy efficiency, and reliability, making them ideal for a variety of environments ranging from hospitals to manufacturing facilities.

One of the most significant features of the Carrier 19XR and 19XRV chillers is their advanced scroll compressor technology. These units employ a tandem scroll design that enhances efficiency while minimizing operational noise. This makes them ideal for urban environments where noise restrictions may be in place. Moreover, the compressors are equipped with variable speed drive options in the 19XRV model, which allows for greater energy savings by adjusting cooling output based on real-time demand.

In addition to their advanced compressors, the 19XR and 19XRV units incorporate the Carrier GreenChoice refrigerant, which has a lower global warming potential compared to traditional refrigerants. This innovative choice not only meets regulatory requirements but also contributes to sustainability goals, making these chillers a responsible choice for environmentally conscious organizations.

The units are engineered with a robust heat exchanger design, which enhances heat transfer efficiency and overall system performance. This ensures optimal operation even in extreme conditions. They feature a microprocessor-based control system that allows for precise monitoring and control of the chiller’s performance, enabling operators to make real-time adjustments to maximize energy efficiency.

The Carrier 19XR and 19XRV chillers also prioritize serviceability. The design incorporates easy access to key components, simplifying maintenance procedures and reducing downtime. This focus on maintainability extends the lifespan of the equipment, leading to lower lifecycle costs.

In terms of connectivity, these chillers are equipped with advanced Building Management System (BMS) integration capabilities. This allows for seamless monitoring and control of the chillers using a centralized platform, facilitating energy management and operational optimization.

Overall, the Carrier 19XR and 19XRV chillers stand out in the market for their blend of cutting-edge technology, energy efficiency, and user-friendly features. They are engineered to meet the demanding needs of modern commercial and industrial applications, making them a preferred choice for facility managers seeking reliable cooling solutions.