Trane trg-trc005-en manual Superheat

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period three

Evaporators

notes

Each distributor has an allowable range of refrigerant flow rates that define its stable operating range. As the size of the evaporator coil increases, it may be necessary to use more than one distributor to feed liquid refrigerant to the coil.

Superheat

B

A

A

C

B

{

C

superheat

Figure 27

Inside the final length of tubes—the location where the temperature difference between the refrigerant and the air is highest—this larger temperature difference accelerates the rate of heat transfer and the refrigerant vapor absorbs even more heat. When the liquid refrigerant has completely evaporated, this additional heat gain to the vapor is called superheating.

Superheating the refrigerant vapor (the line from B to C) shifts it away from the liquid/vapor region and ensures that the refrigerant vapor is completely free of liquid prior to traveling to the compressor.

18	TRG-TRC005-EN

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Contents

Air Conditioning Clinic Refrigeration System Components One of the Fundamental Series Comment CardBusiness Reply Mail Refrigeration System Components Refrigeration System Components PrefaceContents TRG-TRC005-EN Vapor-Compression Refrigeration IntroductionRefrigeration Cycle Refrigeration CyclePeriod one Condenser Air-Cooled Condenser CondensersAir-Cooled Condensers Effect of Subcooling Evaporative Condenser Centrifugal Fan Air-Cooled CondenserEvaporative Condensers Water-Cooled Condensers Water-Cooled CondenserCooling Tower Condenser Capacity Condenser ControlCondenser Control Condensing Temperature Control Vary Condenser Water Flow Rate Vary Entering Water TemperatureCooling Tower Bypass Condenser Flooding Control Air-Cooled Condenser ControlCondensers Finned-Tube Evaporator EvaporatorsFinned-Tube Evaporators Turbulent Flow Superheat Shell-and-Tube Evaporators Shell-and-Tube EvaporatorEvaporator Control Evaporator ControlFace-Split Arrangement Finned-Tube Evaporator Control80ºF Intertwined Arrangement Row-Split Arrangement Shell-and-Tube Evaporator Control Expansion Device Expansion DevicesTXV Control Thermostatic Expansion ValveTXV TXV TXV Operation Psia TXV Too much superheat Superheat SettingSolenoid Valve AccessoriesSolenoid Valve Period five Liquid-Line Filter Drier Liquid-Line Filter DrierSealed type Moisture-Indicating Sight Glass Moisture-Indicating Sight GlassSuction Line Filter Suction Line FilterHot Gas Muffler Hot Gas MufflerShutoff Valve Shutoff ValveAccess Port Access PortReview-Period One ReviewAir-cooled condenser Review-Period TwoReview-Period Four Review-Period ThreeReview-Period Five For more information, refer to the following references Questions for Period QuizQuiz To C To G AnswersGlossary Glossary Glossary Trane Company