Danfoss VMTD MIX Compact 28 Operating guide

OperatingGuide

TermixVMTDMIXCompact28

1.0TableofContents

1.0TableofContents.............................................1

2.0Functionaldescription......................................2

3.0Safetynotes.....................................................3

3.1SafetyNotes–general............................................3

4.0Mounting........................................................4

4.1Mounting...........................................................4

4.2Start-up..............................................................6

4.3Electricalconnections.............................................7

5.0Design.............................................................8

5.1Design...............................................................8

5.2Schematicdiagram................................................9

6.0Controls..........................................................10

6.1Heatingcircuit......................................................10

6.2DHWtemperaturecontrol........................................13

6.3Other.................................................................15

6.4Maintenance........................................................16

7.0Troubleshooting..............................................17

7.1Troubleshootingingeneral......................................17

7.2TroubleshootingDHW............................................18

7.3TroubleshootingHE...............................................19

7.4Disposal.............................................................21

8.0Declaration......................................................23

8.1Declarationofconformity........................................23

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2.0Functionaldescription

Districtheatingsubstationfordirectheatingand
instantaneousdomestichotwaterwiththermostaticor
electroniccontrols.Designedforwall-mounting.

Application

TheTermixVMTDCompact28isacompletesolutionwitha
built-inwaterheaterandaheatingcircuitwithmixingloop.The
substationistheperfectsolutionforapartmentbuildingswithup
to25apartments.

Districtheating(DH)

Thedistrictheatingcircuitisprefabricatedwithaflowcontroller
withintegratedcontrolvalveaswellasstrainersandballvalves.
Furthermorethesubstationisdeliveredwithamixingloop,which
includespumpandnon-returnvalve.

Heating(HE)

Theheatingcircuitisdesignedfordirectconnection.Theflow
controllerwithintegratedcontrolvalvesetstheoptimumoperation
conditionsforradiatorthermostatsinordertoenableindividual
temperaturecontrolineachroom.nThemixingloopcreatesa
suitabletemperaturelevelfortheheatingsystem.

Domestichotwater(DHW)

Thedomestichotwaterispreparedintheplateheatexchanger
andthetemperatureisregulatedwiththermostaticorelectronic
controls.Theefficientheatexchangeroffersexceptionallygood
heatextractionwithhighoutput.NoreadjustmentoftheDHW
temperatureisrequiredafterinstallationandinitialsettingofthe
controls.Thethermostaticcontrolvalveautomaticallyretainsthe
comforttemperatureofthehotwater,evenwhentheheating
systemisinreducedoperationduringsummerorifthedistrict
heatingplantchangesoperatingparametersbetweensummerand
winter.Thiseitherbyloweringorincreasingtheflowtemperature
ofthedistrictheatingwaterand/ortheoperatingpressureinthe
network.

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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.Domestichotwater(DHW)

6.Domesticcoldwater(DCW)

7.Hotwatercirculation(HWC)

Authorizedpersonnelonly

Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandauthorizedpersonnelonly.

Connectionsizes:

DH+HE:
DCW+DHW:
HWC:

Dimensions(mm):

Withoutcover:
H970xW750xD470
Withcover:
H970xW800xD522

Weight(approx.):55kg

Thepipeplacementcandeviatefromtheshowndrawing.Pleasenote
themarkingsonthestation.

G1”(int.thread)
G1”(int.thread)
G¾”(int.thread)

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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,Heatingwithmixingloop

Start-up:

1:Pumpspeed

Setthepumptohighestspeedbeforestart-up.

2:Startpump

Startthepumpandheatthroughthesystem.

3:Openshut-offvalves

Theshut-offvalvesshouldthenbeopenedandtheunitobserved
asitentersservice.Visualcheckingshouldconfirmtemperatures,
pressures,acceptablethermalexpansionandabsenceofleakage.
Ifthesystemoperatesinaccordancewithdesign,itcanbeput
toregularuse.

4:Ventsystem

Switchoffthepumpandventtheinstallationaftertheradiators
havebeenwarmedup.

5:Adjustpumpspeed

Setthepumptothelowestspeedconsistentwithcomfortand
electricityconsumption.
Normallythechange-overswitchissetinthemidposition(default).
Howeverforsystemswithunderfloorheatingorsinglepipeloop
systems,itmaybenecessarytoturnthechange-overswitch
upwards.
Higherpumpspeedsareonlyusediftheheatingrequirement
increases.

Re-thightenconnections

Afterwaterhasbeenaddedtothesystemandthesystemhasbeen
putintooperation,re-tightenALLconnections.

Pump

Thepumpmustbeswitchedoffduringsystemfill.

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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5.0Design

5.1Design

Yoursubstationmightlookdifferentthanthesubstationshown.

Designdescription

B

Heatexchanger,DHW

F

Electroniccontroller

2

Singlecheckvalve

10

Circulatorpump,HE

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11

Domestichotwaterpump

25

Pressuregaugewithballvalve
27AActuator,HE
27BActuator,DHW

30

Flowcontrollerwithintegratedcontrolvalve

48

Airvent,manual

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5.2Schematicdiagram

DH

Supply

DH

Return

Yoursubstationmightlookdifferentthantheschematicdiagramshown.

Schematicdescription

B

Heatexchanger,DHW

F

Electroniccontrollerheating

1

Ballvalve

2

Singlecheckvalve

9

Strainer

10

Circulatorpump

11

Domestichotwaterpump

16

Outdoorsensor

18

Thermometer

19

Surfacesensor

24

Deliveredloosewithunit

25

Pressuregaugewithballvalve

27

Actuator

30

Flowcontrollerwithintegratedcontrolvalve

40

Immersionsensor

48

Airvent,manual

HE
Supply

HE
Return

DHW

DCW

HWC

DHW:DomesticHotWater
DCW:
HWC:
DHSupply:DistrictHeatingSupply
DHReturn:
HESupply:HeatingSupply
HEReturn:HeatingReturn

5.2.1Technicalparameters

Technicalparameters

Nominalpressure:
Max.DHsupplytemperature:
Min.DCWstaticpressure:
Brazingmaterial(HEX):
Heatexchangerstestpressure:30bar
Soundlevel:≤55dB

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DomesticColdWater
HotWaterCirculation

DistrictHeatingReturn

PN16
120°C

0.5bar
Copper

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6.0Controls

6.1Heatingcircuit

6.1.1Differentialpressurecontroller

Thedifferentialpressurecontrollersmoothsoutthefluctuationsin
pressurearrivingfromthedistrictheatingnetwork.Theoperating
pressureinthesubstationisthusheldsteady.

6.1.2HEtemperaturecontrol

TheHEflowtemperatureintheheatingcircuitiscontrolledbythe
HEtemperaturecontroller.

6.1.3AVTBcontroller(30–100°)

Thetemperaturesettingisasfollows:
1=35°C
2=55°C
3=75°C
4=95°C
5=100°C

Thevaluesareintendedasaguide.

Thermostaticcontrol

ThetemperatureoftheHEflowlineisadjustedasfollows:
Toincreasetemperature,turnthehandleonthethermostatic
controllertoselectahighernumber.
Todecreasetemperature,turnthehandleonthethermostatic
controllertoselectalowernumber.

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6.1.4Electric2–waymotorizedvalve

Actuatorswithorwithoutsafetyfunctionareavailablefor3-point
controls.Spring-returnactuatorscanbeusedtoprovidesafety
shut-offintheeventofpowerfailure.

6.1.5Flowcontrollerwithintegratedcontrolvalve

Thecontrollerisaself-actingflowcontrollerwithintegratedcontrol
valve.Thecontrollercloseswhensetmax.flowisexceededand
canbeusedincombinationwithDanfosselectricalactuatorswith
orwithoutsafetyfunction.Springreturnmotorcanbeusedas
safetyfunctionbypowerfailure.

6.1.6Electroniccontrol

Substationswithelectroniccontrolmustbesetinaccordancewith
manufacturer´sinstructions.
Wheretheroomtemperatureiscontrolledbyradiatorthermostats,
itisrecommendedthatthermostatsbesetforminimum
temperatureineachroom.

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6.1.7Circulatorpump

TheUPML,UPMXLcirculatorpumpsaredesignedforcirculating
liquidsinheatingsystemswithvariableflows,internallycontrolled
withthreeproportionalpressurecurvesandthreeconstant
pressure/powercurvestobeselectedviauserinterface.

EuP2015Ready.

TheMAGNA3circulatorpumpsaredesignedforcirculatingliquids
inheatingsystemswithvariableflowswhereyouwanttooptimise
thesettingofthepumpdutypoint,thusreducingenergycosts.

EuP2015Ready.

6.1.8GrundfosUPML/UPMXLinstructions

PP=Proportionalpressure(fastflash)
CP=Constantpressure(slowflash)

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6.2DHWtemperaturecontrol

DHWtemperaturecontrol

TherearevarioustypesofDHWtemperaturecontrolusedin
Danfosssubstations.
DHWtemperatureshouldbeadjustedto45-50°C,asthisprovides
optimalutilisationofDHwater.AtDHWtemperaturesabove55°C,
thepossibilityoflimescaledepositsincreasessignificantly.

6.2.1AVTBcontroller(20–60°)

Thetemperaturesettingisasfollows:
1=20°C
2=35°C
3=50°C
4=60°C
5=70°C

Thevaluesareintendedasaguide.

TheAVTBoperatesatitsbestatDHsupplytemperaturesofupto
90°C.

Thermostaticcontrol

DHWtemperatureisadjustedasfollows:
Toincreasetemperature,turnthehandleonthethermostatic
controllertoselectahighernumber.
Todecreasetemperature,turnthehandleonthethermostatic
controllertoselectalowernumber.

6.2.2Flowcontrollerwithintegratedcontrolvalve

Thecontrollerisaself-actingflowcontrollerwithintegratedcontrol
valve.Thecontrollercloseswhensetmax.flowisexceededand
canbeusedincombinationwithDanfosselectricalactuatorswith
orwithoutsafetyfunction.Springreturnmotorcanbeusedas
safetyfunctionbypowerfailure.

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6.2.3Electric2–waymotorizedvalve

Actuatorswithorwithoutsafetyfunctionareavailablefor3-point
controls.Spring-returnactuatorscanbeusedtoprovidesafety
shut-offintheeventofpowerfailure.

6.2.4Domestichotwaterpump

Important!

Itisnecessarytomountadomestichotwatercirculationpumpon
thewaterheatertoavoidregulationproblems.
Thecirculationpumpcannotbeswitchedoff,sincethiswillresult
inregulationproblems.(noflowatthesensor).

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6.3Other

6.3.1Strainer

Strainersshouldbecleanedregularlybyauthorizedpersonnel.The
frequencyofcleaningwoulddependonoperatingconditionsand
themanufacturer’sinstructions.

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6.4Maintenance

Thesubstationrequireslittlemonitoring,apartfromroutine
checks.Itisrecommendedtoreadtheenergymeteratregular
intervals,andtowritedownthemeterreadings.

RegularinspectionsofthesubstationaccordingtothisInstruction
arerecommended,whichshouldinclude:

Strainers

Cleaningofstrainers.

Meters

Checkingofalloperatingparameterssuchasmeterreadings.

Temperatures

Checkingofalltemperatures,suchasDHsupplytemperatureand
DHWtemperature.

Connections

Checkingallconnectionsforleakages.

Safetyvalves

Theoperationofthesafetyvalvesshouldbecheckedbyturning
thevalveheadintheindicateddirection.

Venting

Checkingthatthesystemisthoroughlyvented.

Authorizedpersonnelonly

Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandauthorizedpersonnelonly.

Inspectionsshouldbecarriedoutminimumeverytwoyears.

SparepartscanbeorderedfromDanfoss.Pleaseensurethatany
enquiryincludesthesubstationserialnumber.

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7.0Troubleshooting

7.1Troubleshootingingeneral

Intheeventofoperatingdisturbances,thefollowingbasicfeatures
shouldbecheckedbeforecarryingoutactualtroubleshooting:

•thesubstationisconnectedtoelectricity,

•thestrainerontheDHsupplypipeisclean,

•thesupplytemperatureoftheDHisatthenormallevel
(summer,atleast60°C-winter,atleast70°C),

•thedifferentialpressureisequaltoorhigherthanthenormal
(local)differentialpressureintheDHnetwork–ifindoubt,ask
theDHplantsupervisor,

•pressureonthesystem-checktheHEpressuregauge.

Authorizedpersonnelonly

Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandauthorizedpersonnelonly.

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7.2TroubleshootingDHW

ProblemPossiblecauseSolution

ToolittleornoDHW.

Taptemperaturetoohigh;DHWtapload
toohigh.

Temperaturedropduringtapping.

Thermostaticcontrolvalvedoesnotclose

Strainerinsupplyorreturnlineclogged.Cleanstrainer(s).

DHWcirculationpumpoutoforderorwith
toolowsetting.

Defectiveorcloggednon-returnvalve.

Noelectricity.Check.

Wrongsettingofautomaticcontrols,ifany.Toadjustanelectroniccontrollerfor

Scalingoftheplateheatexchanger.

Defectivemotorizedvalve.Check(usemanualfunction)–replace.

Defectivetemperaturesensors.

Defectivecontroller.

DCWisbeingmixedwiththeDHW,e.g.ina
defectivethermostaticmixingvalve.

Defectiveorcloggednon-returnvalveon
circulationvalve.

Thermostaticvalveadjustedtoatoohigh
level.

Scalingoftheplateheatexchanger.

LargerDHWflowthanthesubstationhas
beendesignedfor.

TemperaturedifferencebetweenDH
supplyandDHWsetpointtoolow.

Checkcirculationpump.

Replace–clean.

DHW,pls.noteenclosedinstructionsfor
electroniccontroller.

Replace–rinseout.

Check–replace.

Check–replace.

Check–replace. Hotwaterinsometapsbutnotinall.

Replace–clean.

Check–set.

Replace–rinseout.

ReduceDHWflow.

Lowerthesetpointtemperatureorincrease
theDHsupplytemperature.

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7.3TroubleshootingHE

ProblemPossiblecauseSolution

Toolittleornoheat.StrainercloggedinDHorHEcircuit

Unevenheatdistribution.Airpocketsinthesystem.Venttheinstallationthoroughly.

DHsupplytemperaturetoohigh.

DHsupplytemperaturetoolow.

(radiatorcircuit).

ThefilterintheenergymeteronDHcircuit
clogged.

Defectiveorwronglyadjusteddifferential
pressurecontroller.

Sensordefective–orpossiblydirtinthe
valvehousing.

Automaticcontrols,ifany,wronglysetor
defective-possiblypowerfailure.

Pumpoutofoperation.Checkifthepumpisreceivingpowerand

Thepumpissetattoolowspeedof
rotation.

Pressuredrop–thepressuredropon
theradiatorcircuitshowslowerthan
recommendedoperatingpressure.

Airpocketsinthesystem.Venttheinstallationthoroughly.

Limitingofthereturntemperatureadjusted
toolow.

Defectiveradiatorvalves.

Unevenheatdistributioninbuilding
becauseofincorrectlysetbalancingvalves,
orbecausetherearenobalancingvalves.

Diameterofpipetosubstationtoosmallor
branchpipetoolong.

Wrongsettingofthermostatorof
automaticcontrols,ifany.

Defectivecontroller.Thecontrollerdoes
notreactasitshouldaccordingtothe
instructions.

Defectivesensoronself-actingthermostat.

Wrongsettingofautomaticcontrols,ifany.

Defectivecontroller.Thecontrollerdoes
notreactasitshouldaccordingtothe
instructions.

Defectivesensoronself-actingthermostat.

Wrongplacement/fittingofoutdoor
temperaturesensor.

Strainerclogged.Cleangate/strainer.

Cleangate/strainer(s).

Cleanthefilter(afterconsultingtheDH
plantoperator).

Checktheoperationofthedifferential
pressurecontroller–cleanthevalveseatif
required.

Checktheoperationofthethermostat–
cleanthevalveseatifrequired.

Checkifthesettingofthecontroller
iscorrect–seeseparateinstructions.
Checkthepowersupply.Temporary
settingofmotorto“manual”control–see
instructionsonautomaticcontrols.

thatitturns.Checkifthereisairtrappedin
thepumphousing–seepumpmanual.

Setthepumpathigherspeedofrotation.

Fillwateronthesystemandcheckthe
functioningofthepressureexpansion
vesselifrequired.

Adjustaccordingtoinstructions.

Check–replace.

Adjust/installbalancingvalves.

Checkpipedimensions.

Adjustautomaticcontrols,–see
instructionsforautomaticcontrols.

Callautomaticcontrolsmanufactureror
replacetheregulator.

Replacethermostat–orsensoronly.

Adjustautomaticcontrols–seeinstructions
forautomaticcontrols.

Callinautomaticcontrolsmanufactureror
replacecontroller.

Replacethermostat–orsensoronly.

Adjustlocationofoutdoortemperature
sensor.

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ToohighDHreturntemperature.

Noiseinsystem.

Heatloadtoohigh.

Toosmallheatingsurface/toosmall
radiatorscomparedtothetotalheating
requirementofthebuilding.

Poorutilizationofexistingheatingsurface.
Defectivesensoronself-actingthermostat.

Thesystemissinglepipeloop.

Pumppressuretoohigh.Adjustpumptoalowerlevel.

Airinsystem.

Defectiveorincorrectlysetradiatorvalve(s).
Singlepipeloopsystemsrequirespecial
one-piperadiatorvalves.

Dirtinthemotorizedvalveorinthe
differentialpressurecontroller.

Defectivemotorizedvalve,sensoror
automaticcontroller.

Electroniccontrollernotadjustedcorrectly.Adjustaccordingtoinstructions.

Pumppressuretoohigh.Adjustpumptoalowerlevel.

Defectivemotorizedvalve,sensoror
electroniccontroller.

Increasetotalheatingsurface.

Makesuretheheatisdistributedevenly
acrossthefullheatingsurface–openall
radiatorsandkeeptheradiatorsinthe
systemfromheatingupatthebottom.It
isextremelyimportanttokeepthesupply
temperaturetotheradiatorsaslowas
possible,whilemaintainingareasonable
levelofcomfort.

Thesystemshouldfeatureelectronic
controlsaswellasreturnsensors.

Ventthesystem.

Check–set/replace.

Check–cleanout.

Check–replace.

Check–replace.

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7.4Disposal

Disposal

Thisproductshouldbedismantledanditscomponents
sorted,ifpossible,invariousgroupsbeforerecycling
ordisposal.

Alwaysfollowthelocaldisposalregulations.

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8.0Declaration

8.1Declarationofconformity

Category0withelectricalequipment

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