User guide

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Corporate Office: 724.584.5500  Instant Access 24/7 (Parts and Service): 800.458.1960  Parts and Service: 814.437.6861
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HumanMachineInterface(HMI)
Thehumanmachineinterface(HMI)providesauserinterfacewiththePLC,whichcontrolsthe
operationofthechiller.TheHMIallowsdataentryforchillersetup,acceptscommandsto
operatechiller,anddisplayschillerstatus.
PressureReliefValve
Apressurereliefvalveisinstalledonallpressurevesselstosafelyrelievepressureduetofireor
otherabnormaloperatingconditions.EP2Wchillershaveapressurereliefvalveinstalledonthe
water‐cooledcondenser,EP2Achillershaveoneontheliquidline,andEP2Rchillershaveone
installedonthereceiver.Replacethisvalveifitopens.
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Note:VentrefrigerantreliefvalvesinaccordancetoANSI/ASHRAEStandard15,SafetyCodeforMechanical
Refrigeration.
Receiver
ThereceiverisstandardonEP2RunitsandoptionalonEP2AandEP2Wunits.Itisprimarilya
liquidstoragetanktoholdliquidrefrigerantwhennotincirculation.Sinceanair‐cooled
condenserlocatedoutdoorsprovidestherefrigerationcyclecooling,therefrigerantchargewill
varyfromwintertosummeroperation.Duringthesummermonths,thereceiverholdsthe
excessrefrigerantchargerequiredinthewinter.Thereceiveralsoaidsinholdingthe
refrigerantchargewhileinpumpdown.
RefrigerantFilter/Drier
Thefilter/drierislocatedintheliquidlineafterthecondenser.Itremovesanymoistureand/or
foreignmatterthatmayhavegottenintotherefrigerantstream.Moistureandforeignmatter
cancauseseriousdamagetothecomponentsofarefrigerationsystem.Forthisreason,itis
importantthatthechillerbeequippedwithacleanfilter/drier.Replacethefilter/driercoreif
anyofthefollowingconditionsoccur.
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• Openingtherefrigerationsystemtotheatmosphereforrepairsormaintenance
• Indicationofmoistureinthesightglass
• Anexcessivepressuredropdevelopsacrossthefilter/drier(Asignificanttemperature
differencebetweenthefilterinletandoutletindicatesthis.)
RefrigerantServiceValve
Amanualtwo‐wayballvalveisprovidedintherefrigerantliquidlinejustdownstreamofthe
condenserorreceiver.
RefrigerantSightGlass
Therefrigerantsightglassislocatedontheliquidline.Itallowstheoperatororservice
techniciantoobservetheflowofliquidrefrigerantinthecircuit.Prolongedperiodsoffoaming
inthesightglassmayindicatealowrefrigerantconditionorarestrictionintheliquidline.
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