OperatingGuide
TermixVXCompact28
1.0TableofContents
1.0TableofContents.............................................1
........................................................................2
2.0Functionaldescription......................................3
3.0Safetynotes.....................................................4
3.1 SafetyNotes–general............................................4
4.0Mounting........................................................5
4.1 Mounting...........................................................5
4.2 Start-up..............................................................7
4.3 Electricalconnections.............................................9
5.0Design.............................................................10
5.1 Design...............................................................10
5.2 Schematicdiagram................................................11
6.0Controls..........................................................12
6.1 Heatingcircuit......................................................12
6.2 Other.................................................................16
6.3 Maintenance........................................................18
7.0Troubleshooting..............................................19
7.1 Troubleshootingingeneral......................................19
7.2 TroubleshootingHE...............................................20
7.3 Disposal.............................................................22
8.0Declaration......................................................26
8.1 Declarationofconformity........................................26
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2.0Functionaldescription
Districtheatingsubstationforindirectheating.
Application
TheTermixVXCompact28isacompletesolutionforspaceheating
withoptimalsafety,efficientenergytransfer,service-friendly
constructionandacompactdesign.Thesubstationisapplicable,if
aheatexchangerisrequiredoronaconversiontodistrictheating,
wheretheexistingequipmentisunsuitablefordirectconnection.
TheTermixVXCompact28substationisideal,whereahighlevel
ofsecurityagainstburstpipesandwaterdamageintheheating
systemisrequired.
Districtheating(DH)
Thedistrictheatingcircuitisprefabricatedwithaflowcontroller
withintegratedcontrolvalve,thermometersandballvalves.
Heating(HE)
Theheatingcircuitconsistsofaplateheatexchanger,safetyvalve,
manometer,thermometers,ballvalves,drainvalve,airvalveand
circulationpump.Theheatingtemperaturecanbecontrolled
thermostaticallyorbyanelectroniccontrollerwithanoutdoor
temperaturesensor.Dependingontheapplication,differentheat
exchangersdimensionedforcentralorfloorheatingcanbeused.
Domestichotwater(DHW)
TermixVXCompact28issuppliedwithconnectionpipesforaDHW
tankonthesupplyline.
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3.0Safetynotes
3.1SafetyNotes–general
Thefollowinginstructionsrefertothestandarddesignof
substation.Specialversionsofsubstationsareavailableon
request.
Thisoperatingmanualshouldbereadcarefullybeforeinstallation
andstart-upofthesubstation.Themanufactureracceptsno
liabilityfordamageorfaultsthatresultfromnon-compliancewith
theoperatingmanual.Pleasereadandfollowalltheinstructions
carefullytopreventaccidents,injuryanddamagetoproperty.
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandauthorizedpersonnelonly.
Pleasecomplywiththeinstructionsissuedbythesystem
manufacturerorsystemoperator.
Corrosionprotection
Allpipesandcomponentsaremadeofstainlesssteelandbrass.
Themaximumchloridecompoundsoftheflowmediumshouldnot
behigherthan150mg/l.
Theriskofequipmentcorrosionincreasesconsiderablyifthe
recommendedlevelofpermissiblechloridecompoundsis
exceeded.
Energysource
Thesubstationisdesignedfordistrictheatingastheprimary
sourceofenergy.However,alsootherenergysourcescanbeused
wheretheoperatingconditionsallowitandalwaysarecomparable
todistrictheating.
Application
Thesubstationisdesignedtobeconnectedtothehouse
installationinafrost-freeroom,wherethetemperaturedoesnot
exceed50°Candthehumiditydoesnotexceed60%.Donotcover
orwallupthesubstationorinanyotherwayblocktheentrance
tothestation.
Authorizedpersonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandauthorizedpersonnelonly.
Pleaseobserveinstructionscarefully
Toavoidinjurytopersonsanddamagetothedevice,itisabsolutely
necessarytoreadandobservetheseinstructionscarefully.
Warningofhighpressureandtemperature
Beawareoftheinstallation’spermissiblesystempressureand
temperature.
Themaximumtemperatureoftheflowmediuminthesubstationis
120°C.
Themaximumoperatingpressureofthesubstationis16bar.
Theriskofpersonsbeinginjuredandequipmentdamagedincreases
considerablyiftherecommendedpermissibleoperatingparameters
areexceeded.
Thesubstationinstallationmustbeequippedwithsafetyvalves,
however,alwaysinaccordancewithlocalregulations.
Choiceofmaterial
Choiceofmaterialsalwaysincompliancewithlocallegislation.
Safetyvalve(s)
Werecommendmountingofsafetyvalve(s),however,alwaysin
compliancewithlocalregulations.
Connection
Thesubstationmustbeequippedwithfeaturesthatensurethat
thesubstationcanbeseparatedfromallenergysources(also
powersupply).
Emergency
Incaseofdangeroraccidents-fire,leaksorotherdangerous
circumstances-interruptallenergysourcestothestationif
possible,andseekexperthelp.
Incaseofdiscolouredorbad-smellingdomestichotwater,closeall
shut-offvalvesonthesubstation,informtheoperatingpersonnel
andcallforexperthelpimmediately.
REACH
AllDanfossA/SproductsfulfilltherequirementsinREACH.
OneoftheobligationsinREACHistoinformcustomersabout
presenceofCandidatelistsubstancesifany,weherebyinform
youaboutonesubstanceonthecandidatelist:Theproduct
containsbrasspartswhichcontainslead(CASno:7439-92-1)ina
concentrationabove0.1%w/w.
Storage
Anystorageofthesubstationwhichmaybenecessarypriorto
installationshouldbeinconditionswhicharedryandheated.
Warningofhotsurface
Thesubstationhasgothotsurfaces,whichcancauseskinburns.
Pleasebeextremelycautiousincloseproximitytothesubstation.
Powerfailurecanresultinthemotorvalvesbeingstuckinopen
position.Thesurfacesofthesubstationcangethot,whichcancause
skinburns.Theballvalvesondistrictheatingsupplyandreturnshould
beclosed.
Warningoftransportdamage
Beforesubstationinstallation,pleasemakesurethatthesubstation
hasnotbeendamagedduringtransport.
IMPORTANT-Tighteningofconnections
Duetovibrationsduringtransportallflangeconnections,screwjoints
andelectricalclampandscrewconnectionsmustbecheckedand
tightenedbeforewaterisaddedtothesystem.Afterwaterhasbeen
addedtothesystemandthesystemhasbeenputintooperation,
re-tightenALLconnections.
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4.0Mounting
4.1Mounting
Installationmustbeincompliancewithlocalstandardsand
regulations.
Districtheating(DH)-Inthefollowingsections,DHreferstothe
heatsourcewhichsuppliesthesubstations.Avarietyofenergy
sources,suchasoil,gasorsolarpower,couldbeusedasthe
primarysupplytoDanfosssubstations.Forthesakeofsimplicity,
DHcanbetakentomeantheprimarysupply.
Connections:
1.Districtheating(DH)supply
2.Districtheating(DH)return
3.Heating(HE)supply
4.Heating(HE)return
5.Tankflowline(TFL)
6.Tankreturnline(TRL)
Authorizedpersonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandauthorizedpersonnelonly.
Connectionsizes:
DH+HE:
TFL+TRL:
Dimensions(mm):
Withoutcover:
Withcover:
Weight(approx.): 50kg
Thepipeplacementcandeviatefromtheshowndrawing.Pleasenote
themarkingsonthestation.
G1”(int.thread)
G¾”(int.thread)
H970xW620xD420
H970xW640xD522
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4.1.1Installation
Mounting:
Adequatespace
Pleaseallowadequatespacearoundthesubstationformounting
andmaintenancepurposes.
Orientation
Thestationmustbemountedsothatcomponents,keyholes
andlabelsareplacedcorrectly.Ifyouwishtomountthestation
differentlypleasecontactyoursupplier.
Drillings
Wheresubstationsaretobewall-mounted,drillingsareprovided
inthebackmountingplate.Floormountedunitshavesupport.
Labelling
Eachconnectiononthesubstationislabelled.
Beforeinstallation:
Cleanandrinse
Priortoinstallation,allsubstationpipesandconnectionsshouldbe
cleanedandrinsed.
Keyholeformounting.
Tightening
Duetovibrationduringtransport,allsubstationconnectionsmust
becheckedandtightenedbeforeinstallation.
Unusedconnections
Unusedconnectionsandshut-offvalvesmustbesealedwitha
plug.Shouldtheplugsrequireremoval,thismustonlybedoneby
anauthorizedservicetechnician.
Installation:
Strainer
Ifastrainerissuppliedwiththestationitmustbefittedaccording
toschematicdiagram.Pleasenotethatthestrainermaybe
suppliedloose.
Connections
Internalinstallationanddistrictheatingpipesconnectionsmustbe
madeusingthreaded,flangedorweldedconnections.
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4.2Start-up
Start-up,Indirectheating
Filling:
1:Firstfill
Whencarryingoutfirstfill,theheatexchangermustbeslowlyfilled
withwateruntilitreachesworkingpressure.
2:Pressuregauge
TheHEpressuregaugeindicatesthepressureoftheHEsystem.This
instructionmustbefollowedstrictly,toavoiddangeroussituations.
3:Supplyhose
AballvalvewithplugisinstalledintheHEreturnline.Tofillthe
system,theballvalvemustfirstbeclosed,theplugremovedand
asupplyhoseconnected.Onre-openingtheballvalve,system
fillcancommence.
4:Pre-pressure
Whenfillingthesystemwithwater,thepressuregaugeshouldbe
observedclosely.Theexpansionvesselissuppliedpre-pressurised
to0.5bar.Thepre-pressurerequiredateachsubstationwill
dependonsystemhead(thedistancebetweenthelowestand
highestpointinthesystem),forexample:
5:Fillingstop
Fillingmuststopwhenthepressuregaugeshowsapressure
approximately1-2barhigherthanthepre-pressuresetting.The
ballvalveisthenclosed,thehoseremovedandtheplugputback
in.
Re-tightenconnections
Afterwaterhasbeenaddedtothesystemandthesystemhasbeen
putintooperation,re-tightenALLconnections.
Pump
Thepumpmustbeswitchedoffduringsystemfill.
Height(m) Pressure(bar)
0–5 0,5
5–10 1,0
10–15
1,5
15–20 2,0
Start-up:
1:Pumpspeed
Setthepumptohighestspeedbeforestart-up.
2:Startpump
Startthepumpandheatthroughthesystem.
3:Openshut-offvalves
Theshut-offvalvesshouldthenbeopenedandtheunitobserved
asitentersservice.Visualcheckingshouldconfirmtemperatures,
pressures,acceptablethermalexpansionandabsenceofleakage.
Iftheheatexchangeroperatesinaccordancewithdesign,itcanbe
puttoregularuse.
4:Ventsystem
Switchoffthepumpandventtheinstallationaftertheradiators
havebeenwarmedup.
5:Adjustpumpspeed
Setthepumptothelowestspeedconsistentwithcomfortand
electricityconsumption.
Normallythechange-overswitchissetinthemidposition(default).
Howeverforsystemswithunderfloorheatingorsinglepipeloop
systems,itmaybenecessarytoturnthechange-overswitch
upwards.
Higherpumpspeedsareonlyusediftheheatingrequirement
increases.
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Underfloorheating:
Pumpstopfunction
Ifthesubstationisusedinconnectionwithunderfloorheating,the
circulationpumpmustbeconnectedtothepumpstopfunctionin
theunderfloorheatingcontroller.Thepumpmustbestoppedif
allunderfloorheatingcircuitsareclosed.
Warranty
Ifthisisnotpossible,thenflowmustbecontinuedthroughthe
by-pass.Failingthis,thepumpwillbeatriskofseizureandany
remainingwarrantywillbewithdrawn.
Summeroperation:
Switchoffpump
Insummerthecirculationpumpmustbeswitchedoffandthe
shut-offvalvetoHEsupplyclosed.
Runningpumpbi-weekly
Itisrecommendedtostartupthecirculationpump(for2minutes)
onceamonthduringsummer;theshut-offvalveoftheHEsupply
mustbeshut.
Electroniccontroller
Mostelectroniccontrollerswillstartupthepumpautomatically
(pleasenotemanufacturer´sinstructions).
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4.3Electricalconnections
Beforemakingelectricalconnections,pleasenotethe
following:
Safetynotes
Pleasereadtherelevantpartsofthesafetynotes.
230V
Thesubstationmustbeconnectedto230VACandearth.
Potentialbonding
Potentialbondingshouldbecarriedoutaccording
to60364-4-41:2007andIEC60364-5-54:2011.
Bondingpointonthemountingplatebelowrightcornermarked
withearthsymbol.
Disconnection
Thesubstationmustbeelectricallyconnectedsothatitcanbe
disconnectedforrepairs.
Outdoortemperaturesensor
Outdoorsensorsshouldbemountedsoastoavoidexposureto
directsunlight.Theyshouldnotbeplacedclosetodoors,windows
orventilationoutlets.
Theoutdoorsensormustbeconnectedtothestationonthe
terminalblockundertheelectroniccontrol.
Authorizedelectrician
Electricalconnectionsmustbemadebyanauthorizedelectricianonly.
Localstandards
Electricalconnectionsmustbemadeinaccordancewithcurrent
regulationsandlocalstandards.
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