Trane TRG-TRC011-EN manual Period six

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period six

Review

notes

and vapor refrigerant then flows into the evaporator pan, from which the evaporator spray pump continuously pumps the liquid refrigerant to be sprayed over the tubes. As heat transfers from the chilled water flowing through the tubes to the cooler refrigerant, the refrigerant boils (vaporizes) and the resulting refrigerant vapor is drawn into the absorber.

Inside the absorber, the refrigerant vapor is absorbed by the lithium bromide solution, releasing heat to the cooling water which is circulated through the tubes. Absorption of the refrigerant vapor creates a low pressure area within the absorber, inducing a continuous flow of refrigerant from the evaporator to the absorber. The absorber spray pump mixes concentrated absorbent solution (returning from the generator) with dilute solution (from inside the absorber) and delivers this intermediate solution to the absorber sprays. The lithium bromide solution becomes diluted as it absorbs the refrigerant. To complete the cycle, the generator pump continuously returns the dilute absorbent solution to the generator to be reconcentrated. This cool dilute solution passes through a heat exchanger to be preheated by the hot concentrated solution returning from the generator.

Figure 70

Period Two discussed the various types of absorption water chillers, including the single-effect, double-effect, and direct-fired chillers.

The double-effect absorption chiller includes the same basic components as the single-effect chiller, and also includes an additional generator, heat exchanger, and pump. The high-temperature generator can use steam or a hot liquid such as water as the energy source (indirect-fired) or the combustion of a fossil fuel such as natural gas or oil as the energy source (direct-fired).

This period also introduced the use of the direct-fired absorption chiller/heater to provide both cooling and heating.

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Contents Air Conditioning Clinic Absorption Water Chillers Absorption Water Chillers Preface Contents TRG-TRC004-EN Introduction TRG-TRC011-EN Absorption Refrigeration Cycle Period onePeriod one Reject heat Heat energy Absorption System Fluids High affinity for water refrigerant Components of the Absorption Cycle Conditions Steam or Hot waterrefrigerant vapor Generator Condenser Refrigerant then flows into the evaporator pan Absorber spray pump Solution Heat Exchanger Dilute Generator pump Equilibrium Chart Heat Solution temperature Absorption Chiller Types Period twoSingle-Effect Chiller Absorber Evaporator spray pump Spray pump Generator pump Double-Effect Chiller Vapor Low Temperature condenser Cooling Generator Water Evaporator Absorber Low-temperature generator pump Generator pump Absorption Chiller Types Direct-Fired Chiller Evaporator High-temperature high-temperature Generatorgenerator pump Chiller/Heater Absorption Chiller Types Changeover Absorption Chiller Types Capacity Control Period threePeriod three Energy valve Generator Crystallization 10C 37.8C Capacity Control Capacity Control Capacity Control Heat exchanger bypass Evaporator pan Purge System Isolation valve Maintenance Considerations Period fourPeriod four Maintenance Considerations Test run with alternate fuel, if dual-fuel burner Maintenance Considerations Maintenance Considerations Corrosion inhibitor and performance additive recommendations Application Considerations Period fiveCooling-Water Temperature Limitations Combination Chiller Plants 58F Special Considerations for Direct-Fired Chillers Application Considerations Equipment Rating Standards Review Period sixPeriod six Review Review Review Quiz Questions for PeriodQuiz TRG-TRC011-EN Answers Glossary Glossary Glossary Trane Company