Trane TRG-TRC012-EN User Manual

Air ConditioningClinicHelical-RotaryWater ChillersOne of the Equipment SeriesTRG-TRC012-EN

TRG-TRC012-EN 5period oneComponentsnotesIn the operation of the helical-rotary compressor, refrigerant vapor enters the compressor housing through the

6 TRG-TRC012-ENnotesperiod oneComponentsViewing the compressor from the side shows that after the pockets of refrigerant travel to the right past the

TRG-TRC012-EN 7period oneComponentsnotesContinued rotation of the rotors causes the meshing point to travel toward the discharge end of the compressor

8 TRG-TRC012-ENnotesperiod oneComponentsOil SeparatorThe oil leaves the compressor entrained within the discharged refrigerant vapor.The oil is recove

TRG-TRC012-EN 9period oneComponentsnotesoperation and is, therefore, constantly moving to lower pressure areas of the chiller. In this system, oil flo

10 TRG-TRC012-ENnotesperiod oneComponentsCooling water flows first through the lower tubes of the condenser and then through the upper tubes. This pro

TRG-TRC012-EN 11period oneComponentsnotesExpansion DeviceAn expansion device is used to maintain the pressure difference between the high-pressure (co

12 TRG-TRC012-ENnotesperiod oneComponentsThe orifice plate is another type of expansion device found in helical-rotary chillers. The column of liquid

TRG-TRC012-EN 13period oneComponentsnotesBy removing the vapor portion of the mixture before it gets to the evaporator the separator enhances the effe

14 TRG-TRC012-ENnotesperiod oneComponentsAnother type of evaporator found in helical-rotary chillers is the direct expansion (DX) shell-and-tube evapo

Helical-RotaryWater ChillersOne of the Equipment SeriesA publication ofThe Trane Company—Worldwide Applied Systems Group

TRG-TRC012-EN 15period oneComponentsnotesControls and StarterA microprocessor-based control panel is provided on the chiller to provide accurate chill

16 TRG-TRC012-ENnotesA pressure-enthalpy (p-h) chart illustrates the refrigeration cycle of the helical-rotary water chiller.But first, lets review th

TRG-TRC012-EN 17period twoRefrigeration Cyclenotesseparated from the mixture and routed directly to the suction side of the compressor and the remaini

18 TRG-TRC012-ENnotesperiod twoRefrigeration CycleThe theoretical vapor-compression refrigeration cycle for a helical-rotary water chiller can be plot

TRG-TRC012-EN 19period twoRefrigeration CyclenotesManufacturers are continuously improving their designs of helical-rotary water chillers. New chiller

20 TRG-TRC012-ENnotesperiod twoRefrigeration CycleToday the most commonly used refrigerant in helical-rotary chillers is HCFC-22. Due to the scheduled

TRG-TRC012-EN 21notesperiod threeCompressor Capacity ControlThe capacity of the helical-rotary compressor presented in this clinic is controlled by a

22 TRG-TRC012-ENnotesperiod threeCompressor Capacity ControlAt full load, the slide valve is closed. The compressor pumps its maximum volume of refrig

TRG-TRC012-EN 23period threeCompressor Capacity ControlnotesAs the slide valve continues to open, further unloading the compressor, its radial dischar

24 TRG-TRC012-ENnotesperiod threeCompressor Capacity ControlThe slide valve is operated by a piston and cylinder assembly. Extension and retraction of

Preface© 1999 American Standard Inc. All rights reservedTRG-TRC012-ENiiThe Trane Company believes that it’s incumbent on manufacturers to serve the in

TRG-TRC012-EN 25notesperiod fourMaintenance ConsiderationsThis period discusses general maintenance requirements of helical-rotary water chillers. Alt

26 TRG-TRC012-ENnotesperiod fourMaintenance ConsiderationsThe American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) has p

TRG-TRC012-EN 27period fourMaintenance ConsiderationsnotesDirect-drive, semi-hermetic compressor designs require no periodic maintenance on the compre

28 TRG-TRC012-ENnotesperiod fourMaintenance ConsiderationsSome helical-rotary compressor designs do require periodic maintenance of mechanical system

TRG-TRC012-EN 29period fourMaintenance Considerationsnotesdetermine the level of water treatment required to remove contaminants from the cooling towe

30 TRG-TRC012-ENnotesperiod fourMaintenance ConsiderationsRefrigerant analysis measures contamination levels and determines suitability for continued

TRG-TRC012-EN 31notesperiod fiveApplication ConsiderationsThere are several considerations to address when applying helical-rotary water chillers, inc

32 TRG-TRC012-ENnotesperiod fiveApplication Considerationsis the elimination of the cooling tower. This eliminates the concerns and maintenance requir

TRG-TRC012-EN 33period fiveApplication Considerationsnotesand temperatures that the air-cooled chiller. Generally, air-cooled chillers last 15 to 20 y

34 TRG-TRC012-ENnotesperiod fiveApplication ConsiderationsControlling the refrigerant pressure difference between the evaporator and condenser of a wa

TRG-TRC012-EN iiiContentsIntroduction ...1period one Components ...

TRG-TRC012-EN 35period fiveApplication ConsiderationsnotesConstant or Variable Evaporator Water FlowIn previous designs, chillers were required to mai

36 TRG-TRC012-ENnotesperiod fiveApplication Considerations1) The water flow rate through the chiller’s evaporator must stay between the minimum and ma

TRG-TRC012-EN 37period fiveApplication ConsiderationsnotesShort water loops may be unavoidable in close-coupled or very small applications, particular

38 TRG-TRC012-ENnotesperiod fiveApplication ConsiderationsEquipment Certification StandardsThe Air Conditioning & Refrigeration Institute (ARI) es

TRG-TRC012-EN 39period fiveApplication ConsiderationsnotesThe standard rating conditions used for ARI certification represent typical design temperatu

40 TRG-TRC012-ENnotesLet’s review the main concepts that were covered in this clinic on helical-rotary water chillers.In Period 1, the following compo

TRG-TRC012-EN 41period sixReviewnotesIn Period 2, the refrigeration cycle of the helical-rotary water chiller was examined on a pressure-enthalpy char

42 TRG-TRC012-ENnotesperiod sixReviewIn Period 4, the general maintenance requirements of a helical-rotary water chiller were discussed, including: R

TRG-TRC012-EN 43period sixReviewnotesFor more information, refer to the following references: Trane product catalogs for helical-rotary water chiller

44 TRG-TRC012-ENQuestions for Period 11 What components of the helical-rotary compressor are used to compress the refrigerant?2 What are the 2 functio

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TRG-TRC012-EN 45QuizQuestions for Period 37 At full load, is the slide valve fully closed or fully open?8 Explain how the slide valve varies the refri

46 TRG-TRC012-EN1 Male and female screw rotors2 Bearing lubrication and cooling, and rotor oil injection3 Outside of the tubes4 Electronic expansion v

TRG-TRC012-EN 47air-cooled condenser A type of condenser that rejects the heat of the refrigerant to air flowing through it.ARI Air Conditioning &

48 TRG-TRC012-ENGlossaryvapor is directed back to the compressor while the liquid refrigerant travels on to the evaporator.oil separator The component

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The Trane CompanyWorldwide Applied Systems Group3600 Pammel Creek RoadLa Crosse, WI 54601-7599www.trane.comAn American Standard CompanyLiterature Ord

TRG-TRC012-EN 1notesIntroductionWater chillers are used in a variety of air conditioning and process cooling applications. They are used to make cold

2 TRG-TRC012-ENnotesIntroductionWater chillers using the vapor-compression refrigeration cycle vary by the type of compressor used. Reciprocating and

TRG-TRC012-EN 3notesperiod oneComponentsMany of the components of the helical-rotary water chiller are similar to those of other chiller types.This pa

4 TRG-TRC012-ENnotesperiod oneComponentsCompressorThe helical-rotary chiller uses 2 screw-like rotors to perform the compression process.The rotors ar