Driving Sources | Trane TRG-TRC016-EN guide

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Types of Water Chillers

notes

Water chillers using the vapor-compression refrigeration cycle vary by the type of compressor used. Reciprocating, scroll, helical-rotary, and centrifugal compressors are common types of compressors used in vapor-compression water chillers.

Absorption water chillers make use of the absorption refrigeration cycle.

Driving Sources

compressor-driven heat-driven

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Vapor-compression water chillers use a compressor to move refrigerant around the system. The most common energy source to drive the compressor is an electric motor.

Absorption water chillers use heat to drive the refrigeration cycle. They do not have a mechanical compressor involved in the refrigeration cycle. Steam, hot water, or the burning of oil or natural gas are the most common energy sources for these types of chillers.

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Trane TRG-TRC016-EN manual Driving Sources, Compressor-driven heat-driven

Contents

Air Conditioning Clinic Chilled-Water Systems Business Reply Mail One of the Systems Series Comment Card One of the Systems Series Publication Trane Company Preface Contents Iii Water systems Types of Water Chillers Compressor-driven heat-driven Driving Sources Vapor-Compression Water Chillers Vapor-Compression Cycle Scroll Reciprocating Helical-rotarycentrifugal Compressor Types Variable-Speed Drives Condenser Types Air-Cooled or Water-CooledAir-Cooled or Water-Cooled Condensing Maintenance Low Ambient Operation Efficiency Comparison Packaged or Split Components Packaged Air-Cooled Chiller Remote Evaporator Barrel Remote Air-Cooled Condenser Indoor Air-Cooled Condenser Absorption Water Chillers Absorption Refrigeration Cycle Absorption Chillers Offer Choice Single-effectdouble-effect Direct-fired Absorption Chiller Types Equipment Rating Standards Equipment Rating StandardsAir-Conditioning & Refrigeration Institute ARI Part-Load Efficiency Rating Integrated Part-Load Value IplvNon-Standard Part-Load Value Nplv Evaporator Condenser Rating Chiller type Flow rate Standard Rating Conditions QBtu/hr = 500 ⋅ flow rate ⋅ ∆T Flow Rates and Temperatures ARI conditions Low-flow conditions ASHRAE/IESNA Standard Electric Vapor-Compression ChillersEnergy Standard Chiller type Capacity Water-Cooled Absorption Chillers Ashrae Standard Chilled-Water System Components Chilled-Water System Design Chilled-Water System Load-Terminal Control Load-Terminal Control Options Three-Way Valve Control Two-Way Valve Control Face-and-Bypass Damper Control Chiller Evaporator Flow Three-way modulating valveConstant flow is most common Variable flow is possible Single-Chiller System Redundancy Part-load efficiency Multiple-Chiller Systems Single Pump Parallel Configuration Dedicated Pumps Percent flow Chillers Piped in Series Series Configuration Equal Set Points Staggered Set Points Primary-Secondary Decoupled Configuration Primary-Secondary Configuration Bypass pipe should be free of restrictions Primary-Secondary System Rules Production Loop Manifolded Production Pumps Distribution Loop Load terminals should use two-way modulating control valves Bypass pipe should be free of restrictions Variable-speed control riding the pump curve Varying Distribution Flow Multiple Distribution Pumps Distribution Tertiary Pumping Distribution Loop Characteristics Primary-Secondary System Rules Primary-Secondary System Operation System Operation Deficit Flow Excess Flow Control of Primary-Secondary System Types of Fluid Flow Meters Pressure-basedTurbine and impeller Vortex Magnetic Ultrasonic Temperature-Based Calculations Alternate Fuel Choice Electric Utility Deregulation Indirectly-coupled, gas-engine chillers Fuel Choice Options Low-Flow Systems Chiller Efficiency Improvements Trend Toward Lower Flow Rates Greater Focus on System Efficiency Low-Flow Systems Variable-Primary-Flow Systems Variable-Primary-Flow Systems Critical VPF System Requirements Preferential Loading Preferential Chiller Loading Sidestream Configuration Heat Recovery Heat-Recovery Chiller Heat-recovery Auxiliary Dual condenser Condenser Heat pump Heat-Recovery Chiller Options Mode Heat-Recovery Chiller Efficiency Unloadingwith Control of a Heat-Recovery Chiller Asymmetric Design Asymmetric DesignDifferent chiller Capacities Different chiller Swing Chiller Chiller Free Cooling Free CoolingAirside economizer Waterside economizer Plate-and-Frame Heat Exchanger Refrigerant Migration Application Outside the Operating Range of the Chiller Application Outside Range of Chiller Chiller-Plant Control Chiller Controls What Is Important? Chiller Sequencing Chiller Sequencing Temperature Flow Capacity Chiller Rotation Small electric Chiller largeelectric chiller Heat Recovery Variable-Primary-Flow Systems Failure Recovery and Contingency Planning System Failure RecoveryMaintain flow of chilled water Keep it simple Notify the operator Allow the operator to intervene Contingency Planning System Tuning System TimersLoad-confirmation timer Staging-interval timer Unload Before Start Soft Loading Chilled-Water Set Point Control System Optimization System Optimization Chilled Water Reset ProsCons Tower Condenser-Water Temperature Control of Condensing Pressure Operator Interface Operator Training and Support Operator Interface Ashrae Guideline Vapor-compression water chillers Review-Period One Load-terminal control Review-Period Two Review-Period Three Review-Period Four For more information, refer to the following references Quiz 109 Answers 111 Glossary 113 114 115 Trane Company