
OperatingGuide
TermixVMTD-F-B
1.0TableofContents
1.0TableofContents.............................................1
........................................................................2
2.0Functionaldescription......................................3
3.0Safetynotes.....................................................4
3.1SafetyNotes–general............................................4
4.0Mounting........................................................5
4.1Mounting...........................................................5
4.2Start-up..............................................................6
4.3Electricalconnections.............................................7
5.0Design.............................................................8
5.1Design...............................................................8
5.2Schematicdiagram................................................9
6.0Controls..........................................................10
6.1Heatingcircuit......................................................10
6.2DHWtemperaturecontrol........................................11
6.3Other.................................................................11
6.4Maintenance........................................................14
7.0Troubleshooting..............................................15
7.1Troubleshootingingeneral......................................15
7.2TroubleshootingDHW............................................15
7.3TroubleshootingHE...............................................16
7.4Disposal.............................................................17
8.0Declaration......................................................18
8.1Declarationofconformity........................................18
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OperatingGuideTermixVMTD-F-B
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OperatingGuideTermixVMTD-F-B
2.0Functionaldescription
Districtheatingsubstationfordirectheatingand
instantaneousdomestichotwater .
Application
TheTermixVMTD-F-Bisacompletesolutionwithbuilt-inwater
heaterandadifferentialpressurecontrolledheatingsystem.Termix
VMTD-F-Bisapplicableforsingleandmulti-familyhousesandfor
decentralizedsystems.
Districtheating(DH)
Thesubstationisprefabricatedwithadifferentialpressure
controller,attingpieceandsensorpocketsforinsertionofaheat
meteraswellasstrainerandballvalves.
Heating(HE)
Theheatingcircuitisdesignedfordirectgenerationofheat.
Thedifferentialpressurecontrolsetstheoptimumoperation
conditionsforradiatorthermostaticvalvesinordertoenable
individualtemperaturecontrolineachroom.Inordertoenablea
time-dependingtemperaturecontrolprogram,azonevalvewith
actuatorandaroomthermostatcanbeincludedasanoption.
Domestichotwater(DHW)
Thedomestichotwaterispreparedintheheatexchangerandthe
temperatureisregulatedwithathermostaticcontrolvalve.The
patentedsensoracceleratoracceleratestheclosingoftheDanfoss
AVTBvalveandprotectstheheatexchangeragainstoverheating
andlimescaleformation.TheheatexchangercoolstheDHwater
veryefciently,therebycreatingaverygoodoperatingeconomy.
ThesensoracceleratorandAVTBvalvealsoworksasabypass
keepingthehousesupplylinewarm.Thisshortensthewaiting
periodsduringsummerwhentheheatingsystemisinreduced
operation.Thesensoracceleratorhelpstoensureastablehot
watertemperatureregardlessofvaryingloads,owtemperatures
anddifferentialpressurewithouttheneedforreadjustingthevalve.
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OperatingGuideTermixVMTD-F-B
3.0Safetynotes
3.1SafetyNotes–general
Thefollowinginstructionsrefertothestandarddesignof
substation.Specialversionsofsubstationsareavailableon
request.
Thisoperatingmanualshouldbereadcarefullybeforeinstallation
andstart-upofthesubstation.Themanufactureracceptsno
liabilityfordamageorfaultsthatresultfromnon-compliancewith
theoperatingmanual.Pleasereadandfollowalltheinstructions
carefullytopreventaccidents,injuryanddamagetoproperty.
Assembly,start-upandmaintenanceworkmustbeperformedby
qualiedandauthorizedpersonnelonly.
Pleasecomplywiththeinstructionsissuedbythesystem
manufacturerorsystemoperator.
Corrosionprotection
Allpipesandcomponentsaremadeofstainlesssteelandbrass.
Themaximumchloridecompoundsoftheowmediumshouldnot
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
qualiedandauthorizedpersonnelonly.
Pleaseobserveinstructionscarefully
Toavoidinjurytopersonsanddamagetothedevice,itisabsolutely
necessarytoreadandobservetheseinstructionscarefully.
Warningofhighpressureandtemperature
Beawareoftheinstallation’spermissiblesystempressureand
temperature.
Themaximumtemperatureoftheowmediuminthesubstationis
120°C.
Themaximumoperatingpressureofthesubstationis10bar .PN16
versionsareavailableonenquiry.
Theriskofpersonsbeinginjuredandequipmentdamagedincreases
considerablyiftherecommendedpermissibleoperatingparameters
areexceeded.
Thesubstationinstallationmustbeequippedwithsafetyvalves,
however,alwaysinaccordancewithlocalregulations.
Choiceofmaterial
Choiceofmaterialsalwaysincompliancewithlocallegislation.
Safetyvalve(s)
Werecommendmountingofsafetyvalve(s),however,alwaysin
compliancewithlocalregulations.
Connection
Thesubstationmustbeequippedwithfeaturesthatensurethat
thesubstationcanbeseparatedfromallenergysources(also
powersupply).
Emergency
Incaseofdangeroraccidents-re,leaksorotherdangerous
circumstances-interruptallenergysourcestothestationif
possible,andseekexperthelp.
Incaseofdiscolouredorbad-smellingdomestichotwater,closeall
shut-offvalvesonthesubstation,informtheoperatingpersonnel
andcallforexperthelpimmediately.
Storage
Anystorageofthesubstationwhichmaybenecessarypriorto
installationshouldbeinconditionswhicharedryandheated.
Warningofhotsurface
Thesubstationhasgothotsurfaces,whichcancauseskinburns.
Pleasebeextremelycautiousincloseproximitytothesubstation.
Powerfailurecanresultinthemotorvalvesbeingstuckinopen
position.Thesurfacesofthesubstationcangethot,whichcancause
skinburns.Theballvalvesondistrictheatingsupplyandreturnshould
beclosed.
Warningoftransportdamage
Beforesubstationinstallation,pleasemakesurethatthesubstation
hasnotbeendamagedduringtransport.
IMPORTANT-Tighteningofconnections
Duetovibrationsduringtransportallangeconnections,screwjoints
andelectricalclampandscrewconnectionsmustbecheckedand
tightenedbeforewaterisaddedtothesystem.Afterwaterhasbeen
addedtothesystemandthesystemhasbeenputintooperation,
re-tightenALLconnections.
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OperatingGuideTermixVMTD-F-B
4.0Mounting
4.1Mounting
Installationmustbeincompliancewithlocalstandardsand
regulations.
Districtheating(DH)-Inthefollowingsections,DHreferstothe
heatsourcewhichsuppliesthesubstations.Avarietyofenergy
sources,suchasoil,gasorsolarpower,couldbeusedasthe
primarysupplytoDanfosssubstations.Forthesakeofsimplicity,
DHcanbetakentomeantheprimarysupply.
Connections:
1.Hotwatercirculation(HWC)(Optional)
2.Districtheating(DH)supply
3.Districtheating(DH)return
4.Coldwatermains(CWM)
5.Domesticcoldwater(DCW)
6.Domestichotwater(DHW)
7.Heating(HE)supply
8.Heating(HE)return
Authorizedpersonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualiedandauthorizedpersonnelonly.
Thepipeplacementcandeviatefromtheshowndrawing.Pleasenote
themarkingsonthestation.
Connectionsizes:
DH+HE:
CWM+DCW+DHW:
G¾”(int.thread)
G¾”(int.thread)
Dimensions(mm):
Withoutcover:
H710xW528xD150
Withcover(mountonwallvariant):
H800xW540xD190
Withcover(built-inwallvariant):
H915–980xW610xD150
Weight(approx.):20kg
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OperatingGuideTermixVMTD-F-B
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
Ifastrainerissuppliedwiththestationitmustbettedaccording
toschematicdiagram.Pleasenotethatthestrainermaybe
suppliedloose.
Connections
Internalinstallationanddistrictheatingpipesconnectionsmustbe
madeusingthreaded,angedorweldedconnections.
4.2Start-up
Start-up,Directheating
Theshut-offvalvesshouldbeopenedandtheunitobservedas
itentersservice.Visualcheckingshouldconrmtemperatures,
pressures,acceptablethermalexpansionandabsenceofleakage.
Iftheheatexchangeroperatesinaccordancewithdesign,itcanbe
puttoregularuse.
Re-thightenconnections
Afterwaterhasbeenaddedtothesystemandthesystemhasbeen
putintooperation,re-tightenALLconnections.
Afterwaterhasbeenaddedtothesystemandthesystemhasbeen
putintooperation,re-tightenALLconnections.
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DanfossDistrictEnergy