Dometic SmartStart III - Ooling Ode; Heating Mode; Status Screen Navigation

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COOLING M ODE
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CoolingmodeisenteredwhenCoolisselectedonthetouchscreenorwiththedisplaybuttons.Thesystemwillautomatical lystartcooling
dependingontemperaturesetpoint.Thepumpswilloperateasdescribedinthepumpoperationsection.
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Theboardwillenergizethecompressorrelayifreturnwater/supplywatertemperatureis
abovethecoolingsetpointandthestaging
delayhaselapsed.
Thecompressorwillcontinuetorununtilthecoolingsetpointhasbeenreachedoranalarmconditionexists.Astagewillhavea
minimumruntimeof100secondsbef oreitcanbeturnedoffandaminimumofftimeof
120secondsbeforeitcanbere‐enabled.This
minimumontimeisrequiredtoensurethatthesystemisnotcyclingonandoff andnotallowingthecompressortoproperlywarm‐up.
Thisensuresproperoillubricationofthesystem.Ifthesystemcallsforastagetobetoggledon/off,thenextavailablestagewillbeused
thatmeetsthestagingcriteria.Loadsheddingwilloccurinmultistageoperationwhenapproachingchilledwatersetpoint.Thereversing
valveistoggledtorelieveheadpressureattheendofacompressorruncycle.
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HEATIN G M OD E
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ReverseCycleHeatingmodeisenteredwhenHeatisselectedonthetouchscreenorwiththedisplaybuttons.Thesystemwill
automaticallystartheatingdependingonthetemperaturesetpoint.Thepumpswilloperateasdescribedinthepumpoperationsection.
Thereversingvalverelaywillbeenergizedtochangethe
unittooperateinReverseCycleHeatingmode.
ThePLCwillenergizethecompressorrelayifreturn/supplywatertemperaturebelowtheprogrammedheatingsetpointandthestaging
delayhaselapsed.Thecompressorwillcontinuetorunandthereversingvalvewillremainenergizeduntiltheheatingsetpointhas
beenreachedoranalarmconditionexists.
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ElectricHeatingmodeisenteredwhenElectricHeatisselectedonthetouchscreenorwiththedisplaybuttons.Thesystemwill
automaticallystartheatingdependingonthetemperaturesetpoint.
ThePLCwillenergizetheheaterrelayifreturn/supplywatertemperatureisbelowtheprogrammedsetpointandthestagingdelay
haselapsed
inamultistageconfigura t ion.
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StatusScreenNavigation
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Themainhomescreenisthestatusscreenwherethesinglestageoperationcanbereviewedorinamultistageconfigurationtheusercan
scrollandseethevaluesofthechilledwaterandotherparametersoftheadditionalstages.Theuserwillsimplyusethedownarrowkey
toscrollthroughthevariousparametersbeingdisplayedontheLCDscreen.TheLCDscreenwillalsoindicateonthemainscreenthe
modeofoperationwhetheritisCool,HeatorEHmode.Themainscreenwillalsoindicateifthereisanalarmpresentonthesystemby
flashingthewordalarminthelowerright‐handcornerorLoadsheddingifithasbeenactivated.
Figure2
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