Trane TRG-TRC011-EN manual Maintenance Considerations

Page 56

period four

Maintenance Considerations

notes

Conduct annually or semiannually

Verifies corrosion inhibitor levels

Verifies performance additive levels

Conduct annually

Figure 60

An absorption chiller requires a very deep vacuum to operate efficiently. The introduction of air and other noncondensables into the chiller will adversely affect the chiller’s performance. In a lithium bromide absorption chiller, where the absorbent is a salt, corrosion is a potential problem that must be avoided. It may not be possible to completely prevent corrosion inside the chiller, although it can be reduced or controlled by the addition of a chemical called a corrosion inhibitor.

Corrosion inhibitors are primarily intended to protect the steel components of the chiller from the corrosive action of the lithium bromide-and-water mixture. The inhibitor is added to the lithium bromide solution to promote the formation of a thin protective layer of oxide quickly and uniformly over the steel components inside the chiller. This coating is more impervious to the reaction with water, resulting in longer life for the chiller. Corrosion inhibitors also reduce the production of noncondensable gas that is generated during the corrosion process. The corrosion inhibitor, however, does not directly protect the copper components from corrosion. Corrosion protection for the copper heat transfer components primarily depends on the materials selected to assure maximum design life.

Additionally, most lithium bromide absorption chillers use a chemical performance additive to achieve and maintain design performance. This additive considerably enhances the rate at which refrigerant vapor is absorbed by the lithium bromide solution.

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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