Danfoss Termix VMTD MIX Compact 28 User manual

OperatingGuide
TermixVMTDMIXCompact28
1.0TableofContent
1.0TableofContent.............................................1
2.0Functionaldecription......................................2
3.0Safetynote.....................................................3
3.1SafetyNotes–general............................................3
4.0Mounting........................................................4
4.1Mounting...........................................................4
4.2Start-up..............................................................6
4.3Electricalconnections.............................................7
5.0Deign.............................................................8
5.1Design...............................................................8
5.2Scematicdiagram................................................9
6.0Control..........................................................10
6.1Heatingcircuit......................................................10
6.2DHWtemperaturecontrol........................................13
6.3Oter.................................................................15
6.4Maintenance........................................................16
7.0Troublehooting..............................................17
7.1Troublesootingingeneral......................................17
7.2TroublesootingDHW............................................18
7.3TroublesootingHE...............................................19
7.4Disposal.............................................................21
8.0Declaration......................................................23
8.1Declarationofconformity........................................23
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2.0Functionaldecription
Ditrictheatingubtationfordirectheatingand
intantaneoudometichotwaterwiththermotaticor
electroniccontrol.Deignedforwall-mounting.
Application
TeTermixVMTDCompact28isacompletesolutionwita
built-inwatereaterandaeatingcircuitwitmixingloop.Te
substationisteperfectsolutionforapartmentbuildingswitup
to25apartments.
Ditrictheating(DH)
Tedistricteatingcircuitisprefabricatedwitaflowcontroller
witintegratedcontrolvalveaswellasstrainersandballvalves.
Furtermoretesubstationisdeliveredwitamixingloop,wic
includespumpandnon-returnvalve.
Heating(HE)
Teeatingcircuitisdesignedfordirectconnection.Teflow
controllerwitintegratedcontrolvalvesetsteoptimumoperation
conditionsforradiatortermostatsinordertoenableindividual
temperaturecontrolineacroom.nTemixingloopcreatesa
suitabletemperaturelevelforteeatingsystem.
Dometichotwater(DHW)
Tedomesticotwaterispreparedinteplateeatexcanger
andtetemperatureisregulatedwittermostaticorelectronic
controls.Teefficienteatexcangeroffersexceptionallygood
eatextractionwitigoutput.NoreadjustmentofteDHW
temperatureisrequiredafterinstallationandinitialsettingofte
controls.Tetermostaticcontrolvalveautomaticallyretainste
comforttemperatureofteotwater,evenwenteeating
systemisinreducedoperationduringsummeroriftedistrict
eatingplantcangesoperatingparametersbetweensummerand
winter.Tiseiterbyloweringorincreasingteflowtemperature
oftedistricteatingwaterand/orteoperatingpressureinte
network.
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3.0Safetynote
3.1SafetyNote–general
Thefollowingintructionrefertothetandarddeignof
ubtation.Specialverionofubtationareavailableon
requet.
Tisoperatingmanualsouldbereadcarefullybeforeinstallation
andstart-upoftesubstation.Temanufactureracceptsno
liabilityfordamageorfaultstatresultfromnon-compliancewit
teoperatingmanual.Pleasereadandfollowallteinstructions
carefullytopreventaccidents,injuryanddamagetoproperty.
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandautorizedpersonnelonly.
Pleasecomplywitteinstructionsissuedbytesystem
manufacturerorsystemoperator.
Corroionprotection
Allpipesandcomponentsaremadeofstainlesssteelandbrass.
Temaximumcloridecompoundsofteflowmediumsouldnot
beigertan150mg/l.
Teriskofequipmentcorrosionincreasesconsiderablyifte
recommendedlevelofpermissiblecloridecompoundsis
exceeded.
Energyource
Tesubstationisdesignedfordistricteatingasteprimary
sourceofenergy.However,alsooterenergysourcescanbeused
wereteoperatingconditionsallowitandalwaysarecomparable
todistricteating.
Application
Tesubstationisdesignedtobeconnectedtoteouse
installationinafrost-freeroom,weretetemperaturedoesnot
exceed50°Candteumiditydoesnotexceed60%.Donotcover
orwalluptesubstationorinanyoterwayblockteentrance
totestation.
Choiceofmaterial
Coiceofmaterialsalwaysincompliancewitlocallegislation.
Safetyvalve()
Werecommendmountingofsafetyvalve(s),owever,alwaysin
compliancewitlocalregulations.
Connection
Tesubstationmustbeequippedwitfeaturestatensuretat
tesubstationcanbeseparatedfromallenergysources(also
powersupply).
Emergency
Incaseofdangeroraccidents-fire,leaksoroterdangerous
circumstances-interruptallenergysourcestotestationif
possible,andseekexpertelp.
Incaseofdiscolouredorbad-smellingdomesticotwater,closeall
sut-offvalvesontesubstation,informteoperatingpersonnel
andcallforexpertelpimmediately.
REACH
AllDanfossA/SproductsfulfillterequirementsinREACH.
OneofteobligationsinREACHistoinformcustomersabout
presenceofCandidatelistsubstancesifany,weerebyinform
youaboutonesubstanceontecandidatelist:Teproduct
containsbrasspartswiccontainslead(CASno:7439-92-1)ina
concentrationabove0.1%w/w.
Storage
Anystorageoftesubstationwicmaybenecessarypriorto
installationsouldbeinconditionswicaredryandeated.
Authorizedperonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandautorizedpersonnelonly.
Pleaeoberveintructioncarefully
Toavoidinjurytopersonsanddamagetotedevice,itisabsolutely
necessarytoreadandobserveteseinstructionscarefully.
Warningofhighpreureandtemperature
Beawareofteinstallation’spermissiblesystempressureand
temperature.
Temaximumtemperatureofteflowmediumintesubstationis
120°C.
Temaximumoperatingpressureoftesubstationis16bar.
Teriskofpersonsbeinginjuredandequipmentdamagedincreases
considerablyifterecommendedpermissibleoperatingparameters
areexceeded.
Tesubstationinstallationmustbeequippedwitsafetyvalves,
owever,alwaysinaccordancewitlocalregulations.
Warningofhoturface
Tesubstationasgototsurfaces,wiccancauseskinburns.
Pleasebeextremelycautiousincloseproximitytotesubstation.
Powerfailurecanresultintemotorvalvesbeingstuckinopen
position.Tesurfacesoftesubstationcangetot,wiccancause
skinburns.Teballvalvesondistricteatingsupplyandreturnsould
beclosed.
Warningoftranportdamage
Beforesubstationinstallation,pleasemakesuretattesubstation
asnotbeendamagedduringtransport.
IMPORTANT-Tighteningofconnection
Duetovibrationsduringtransportallflangeconnections,screwjoints
andelectricalclampandscrewconnectionsmustbececkedand
tigtenedbeforewaterisaddedtotesystem.Afterwaterasbeen
addedtotesystemandtesystemasbeenputintooperation,
re-tigtenALLconnections.
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4.0Mounting
4.1Mounting
Installationmustbeincompliancewitlocalstandardsand
regulations.
Districteating(DH)-Intefollowingsections,DHreferstote
eatsourcewicsuppliestesubstations.Avarietyofenergy
sources,sucasoil,gasorsolarpower,couldbeusedaste
primarysupplytoDanfosssubstations.Fortesakeofsimplicity,
DHcanbetakentomeanteprimarysupply.
Connection:
1.Districteating(DH)supply
2.Districteating(DH)return
3.Heating(HE)supply
4.Heating(HE)return
5.Domesticotwater(DHW)
6.Domesticcoldwater(DCW)
7.Hotwatercirculation(HWC)
Connectionize:
DH+HE:G1”(int.tread)
DCW+DHW:G1”(int.tread)
HWC:G¾”(int.tread)
Dimenion(mm):
Witoutcover:
H970xW750xD470
Witcover:
H970xW800xD522
Weight(approx.):55kg
Authorizedperonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandautorizedpersonnelonly.
Thepipeplacementcandeviatefromtheshowndrawing.Pleasenote
themarkingsonthestation.
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4.1.1Intallation
Mounting:
Adequatepace
Pleaseallowadequatespacearoundtesubstationformounting
andmaintenancepurposes.
Orientation
Testationmustbemountedsotatcomponents,keyoles
andlabelsareplacedcorrectly.Ifyouwistomounttestation
differentlypleasecontactyoursupplier.
Drilling
Weresubstationsaretobewall-mounted,drillingsareprovided
intebackmountingplate.Floormountedunitsavesupport.
Labelling
Eacconnectionontesubstationislabelled.
Beforeintallation:
Cleanandrine
Priortoinstallation,allsubstationpipesandconnectionssouldbe
cleanedandrinsed.
Tightening
Duetovibrationduringtransport,allsubstationconnectionsmust
bececkedandtigtenedbeforeinstallation.
Unuedconnection
Unusedconnectionsandsut-offvalvesmustbesealedwita
plug.Souldteplugsrequireremoval,tismustonlybedoneby
anautorizedservicetecnician.
Intallation:
Strainer
Ifastrainerissuppliedwittestationitmustbefittedaccording
toscematicdiagram.Pleasenotetattestrainermaybe
suppliedloose.
Connection
Internalinstallationanddistricteatingpipesconnectionsmustbe
madeusingtreaded,flangedorweldedconnections.
Keyholeformounting.
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4.2Start-up
Start-up,Heatingwithmixingloop
Start-up:
1:Pumppeed
Settepumptoigestspeedbeforestart-up.
2:Startpump
Starttepumpandeattrougtesystem.
3:Openhut-offvalve
Tesut-offvalvessouldtenbeopenedandteunitobserved
asitentersservice.Visualceckingsouldconfirmtemperatures,
pressures,acceptabletermalexpansionandabsenceofleakage.
Iftesystemoperatesinaccordancewitdesign,itcanbeput
toregularuse.
4:Ventytem
Switcofftepumpandventteinstallationafterteradiators
avebeenwarmedup.
5:Adjutpumppeed
Settepumptotelowestspeedconsistentwitcomfortand
electricityconsumption.
Normallytecange-overswitcissetintemidposition(default).
Howeverforsystemswitunderflooreatingorsinglepipeloop
systems,itmaybenecessarytoturntecange-overswitc
upwards.
Higerpumpspeedsareonlyusedifteeatingrequirement
increases.
Re-thightenconnection
Afterwaterasbeenaddedtotesystemandtesystemasbeen
putintooperation,re-tigtenALLconnections.
Pump
Tepumpmustbeswitcedoffduringsystemfill.
Underfloorheating:
Pumptopfunction
Iftesubstationisusedinconnectionwitunderflooreating,te
circulationpumpmustbeconnectedtotepumpstopfunctionin
teunderflooreatingcontroller.Tepumpmustbestoppedif
allunderflooreatingcircuitsareclosed.
Warranty
Iftisisnotpossible,tenflowmustbecontinuedtrougte
by-pass.Failingtis,tepumpwillbeatriskofseizureandany
remainingwarrantywillbewitdrawn.
Summeroperation:
Switchoffpump
Insummertecirculationpumpmustbeswitcedoffandte
sut-offvalvetoHEsupplyclosed.
Runningpumpbi-weekly
Itisrecommendedtostartuptecirculationpump(for2minutes)
onceamontduringsummer;tesut-offvalveofteHEsupply
mustbesut.
Electroniccontroller
Mostelectroniccontrollerswillstartuptepumpautomatically
(pleasenotemanufacturer´sinstructions).
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4.3Electricalconnection
Beforemakingelectricalconnection,pleaenotethe
following:
Safetynote
Pleasereadterelevantpartsoftesafetynotes.
230V
Tesubstationmustbeconnectedto230VACandeart.
Potentialbonding
Potentialbondingsouldbecarriedoutaccording
to60364-4-41:2007andIEC60364-5-54:2011.
Bondingpointontemountingplatebelowrigtcornermarked
witeartsymbol.
Diconnection
Tesubstationmustbeelectricallyconnectedsotatitcanbe
disconnectedforrepairs.
Outdoortemperatureenor
Outdoorsensorssouldbemountedsoastoavoidexposureto
directsunligt.Teysouldnotbeplacedclosetodoors,windows
orventilationoutlets.
Teoutdoorsensormustbeconnectedtotestationonte
terminalblockunderteelectroniccontrol.
Authorizedelectrician
Electricalconnectionsmustbemadebyanautorizedelectricianonly.
Localtandard
Electricalconnectionsmustbemadeinaccordancewitcurrent
regulationsandlocalstandards.
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5.0Deign
5.1Deign
Yoursubstationmightlookdifferentthanthesubstationshown.
Deigndecription
BHeatexcanger,DHW11Domesticotwaterpump30Flowcontrollerwitintegratedcontrolvalve
FElectroniccontroller25Pressuregaugewitballvalve48Airvent,manual
2Singlececkvalve27AActuator,HE
10Circulatorpump,HE27BActuator,DHW
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5.2Schematicdiagram
DH
Supply
HE
Supply
DH
Return
HE
Return
DHW
DCW
HWC
Yoursubstationmightlookdifferentthantheschematicdiagramshown.
Schematicdecription
BHeatexcanger,DHW11Domesticotwaterpump25Pressuregaugewitballvalve
FElectroniccontrollereating16Outdoorsensor27Actuator
1Ballvalve18Termometer30Flowcontrollerwitintegratedcontrolvalve
2Singlececkvalve19Surfacesensor40Immersionsensor
9Strainer24Deliveredloosewitunit48Airvent,manual
10Circulatorpump
DHW:DomesticHotWater
DCW:DomesticColdWater
HWC:HotWaterCirculation
DHSupply:DistrictHeatingSupply
DHReturn:DistrictHeatingReturn
HESupply:HeatingSupply
HEReturn:HeatingReturn
5.2.1Technicalparameter
Technicalparameter
Nominalpressure:PN16
Max.DHsupplytemperature:120°C
Min.DCWstaticpressure:0.5bar
Brazingmaterial(HEX):Copper
Heatexcangerstestpressure:30bar
Soundlevel:≤55dB
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6.0Control
6.1Heatingcircuit
6.1.1Differentialpreurecontroller
Tedifferentialpressurecontrollersmootsouttefluctuationsin
pressurearrivingfromtedistricteatingnetwork.Teoperating
pressureintesubstationistuseldsteady.
6.1.2HEtemperaturecontrol
TeHEflowtemperatureinteeatingcircuitiscontrolledbyte
HEtemperaturecontroller.
6.1.3AVTBcontroller(30–100°)
Tetemperaturesettingisasfollows:
1=35°C
2=55°C
3=75°C
4=95°C
5=100°C
Thevaluesareintendedasaguide.
Thermotaticcontrol
TetemperatureofteHEflowlineisadjustedasfollows:
Toincreasetemperature,turnteandleontetermostatic
controllertoselectaigernumber.
Todecreasetemperature,turnteandleontetermostatic
controllertoselectalowernumber.
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6.1.4Electric2–waymotorizedvalve
Actuatorswitorwitoutsafetyfunctionareavailablefor3-point
controls.Spring-returnactuatorscanbeusedtoprovidesafety
sut-offinteeventofpowerfailure.
6.1.5Flowcontrollerwithintegratedcontrolvalve
Tecontrollerisaself-actingflowcontrollerwitintegratedcontrol
valve.Tecontrollercloseswensetmax.flowisexceededand
canbeusedincombinationwitDanfosselectricalactuatorswit
orwitoutsafetyfunction.Springreturnmotorcanbeusedas
safetyfunctionbypowerfailure.
6.1.6Electroniccontrol
Substationswitelectroniccontrolmustbesetinaccordancewit
manufacturer´sinstructions.
Wereteroomtemperatureiscontrolledbyradiatortermostats,
itisrecommendedtattermostatsbesetforminimum
temperatureineacroom.
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6.1.7Circulatorpump
TeUPML,UPMXLcirculatorpumpsaredesignedforcirculating
liquidsineatingsystemswitvariableflows,internallycontrolled
wittreeproportionalpressurecurvesandtreeconstant
pressure/powercurvestobeselectedviauserinterface.
EuP2015Ready.
TeMAGNA3circulatorpumpsaredesignedforcirculatingliquids
ineatingsystemswitvariableflowswereyouwanttooptimise
tesettingoftepumpdutypoint,tusreducingenergycosts.
EuP2015Ready.
6.1.8GrundfoUPML/UPMXLintruction
PP=Proportionalpressure(fastflas)
CP=Constantpressure(slowflas)
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6.2DHWtemperaturecontrol
DHWtemperaturecontrol
TerearevarioustypesofDHWtemperaturecontrolusedin
Danfosssubstations.
DHWtemperaturesouldbeadjustedto45-50°C,astisprovides
optimalutilisationofDHwater.AtDHWtemperaturesabove55°C,
tepossibilityoflimescaledepositsincreasessignificantly.
6.2.1AVTBcontroller(20–60°)
Tetemperaturesettingisasfollows:
1=20°C
2=35°C
3=50°C
4=60°C
5=70°C
Thevaluesareintendedasaguide.
TeAVTBoperatesatitsbestatDHsupplytemperaturesofupto
90°C.
Thermotaticcontrol
DHWtemperatureisadjustedasfollows:
Toincreasetemperature,turnteandleontetermostatic
controllertoselectaigernumber.
Todecreasetemperature,turnteandleontetermostatic
controllertoselectalowernumber.
6.2.2Flowcontrollerwithintegratedcontrolvalve
Tecontrollerisaself-actingflowcontrollerwitintegratedcontrol
valve.Tecontrollercloseswensetmax.flowisexceededand
canbeusedincombinationwitDanfosselectricalactuatorswit
orwitoutsafetyfunction.Springreturnmotorcanbeusedas
safetyfunctionbypowerfailure.
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6.2.3Electric2–waymotorizedvalve
Actuatorswitorwitoutsafetyfunctionareavailablefor3-point
controls.Spring-returnactuatorscanbeusedtoprovidesafety
sut-offinteeventofpowerfailure.
6.2.4Dometichotwaterpump
Important!
Itisnecessarytomountadomesticotwatercirculationpumpon
tewatereatertoavoidregulationproblems.
Tecirculationpumpcannotbeswitcedoff,sincetiswillresult
inregulationproblems.(noflowattesensor).
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6.3Other
6.3.1Strainer
Strainerssouldbecleanedregularlybyautorizedpersonnel.Te
frequencyofcleaningwoulddependonoperatingconditionsand
temanufacturer’sinstructions.
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6.4Maintenance
Tesubstationrequireslittlemonitoring,apartfromroutine
cecks.Itisrecommendedtoreadteenergymeteratregular
intervals,andtowritedowntemeterreadings.
RegularinspectionsoftesubstationaccordingtotisInstruction
arerecommended,wicsouldinclude:
Strainer
Cleaningofstrainers.
Meter
Ceckingofalloperatingparameterssucasmeterreadings.
Temperature
Ceckingofalltemperatures,sucasDHsupplytemperatureand
DHWtemperature.
Connection
Ceckingallconnectionsforleakages.
Safetyvalve
Teoperationoftesafetyvalvessouldbececkedbyturning
tevalveeadinteindicateddirection.
Venting
Ceckingtattesystemistorouglyvented.
Inspectionsshouldbecarriedoutminimumeverytwoyears.
SparepartscanbeorderedfromDanfoss.Pleaseensuretatany
enquiryincludestesubstationserialnumber.
Authorizedperonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandautorizedpersonnelonly.
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7.0Troublehooting
7.1Troublehootingingeneral
Inteeventofoperatingdisturbances,tefollowingbasicfeatures
souldbececkedbeforecarryingoutactualtroublesooting:
•tesubstationisconnectedtoelectricity,
•testraineronteDHsupplypipeisclean,
•tesupplytemperatureofteDHisattenormallevel
(summer,atleast60°C-winter,atleast70°C),
•tedifferentialpressureisequaltoorigertantenormal
(local)differentialpressureinteDHnetwork–ifindoubt,ask
teDHplantsupervisor,
•pressureontesystem-ceckteHEpressuregauge.
Authorizedperonnelonly
Assembly,start-upandmaintenanceworkmustbeperformedby
qualifiedandautorizedpersonnelonly.
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7.2TroublehootingDHW
ProblemPossiblecauseSolution
Strainerinsupplyorreturnlineclogged.Cleanstrainer(s).
DHWcirculationpumpoutoforderorwit
toolowsetting.
Ceckcirculationpump.
Defectiveorcloggednon-returnvalve.Replace–clean.
Noelectricity.Ceck.
Wrongsettingofautomaticcontrols,ifany.Toadjustanelectroniccontrollerfor
DHW,pls.noteenclosedinstructionsfor
electroniccontroller.
Scalingofteplateeatexcanger.Replace–rinseout.
Defectivemotorizedvalve.Ceck(usemanualfunction)–replace.
Defectivetemperaturesensors.Ceck–replace.
ToolittleornoDHW.
Defectivecontroller.Ceck–replace.
DCWisbeingmixedwitteDHW,e.g.ina
defectivetermostaticmixingvalve.
Ceck–replace. Hotwaterinsometapsbutnotinall.
Defectiveorcloggednon-returnvalveon
circulationvalve.
Replace–clean.
Taptemperaturetooig;DHWtapload
tooig.
Termostaticvalveadjustedtoatooig
level.
Ceck–set.
Scalingofteplateeatexcanger.Replace–rinseout.
Temperaturedropduringtapping.
LargerDHWflowtantesubstationas
beendesignedfor.
ReduceDHWflow.
TermostaticcontrolvalvedoesnotcloseTemperaturedifferencebetweenDH
supplyandDHWsetpointtoolow.
Lowertesetpointtemperatureorincrease
teDHsupplytemperature.
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7.3TroublehootingHE
ProblemPossiblecauseSolution
Toolittleornoeat.StrainercloggedinDHorHEcircuit
(radiatorcircuit).
Cleangate/strainer(s).
TefilterinteenergymeteronDHcircuit
clogged.
Cleantefilter(afterconsultingteDH
plantoperator).
Defectiveorwronglyadjusteddifferential
pressurecontroller.
Ceckteoperationoftedifferential
pressurecontroller–cleantevalveseatif
required.
Sensordefective–orpossiblydirtinte
valveousing.
Ceckteoperationoftetermostat–
cleantevalveseatifrequired.
Automaticcontrols,ifany,wronglysetor
defective-possiblypowerfailure.
Ceckiftesettingoftecontroller
iscorrect–seeseparateinstructions.
Cecktepowersupply.Temporary
settingofmotorto“manual”control–see
instructionsonautomaticcontrols.
Pumpoutofoperation.Ceckiftepumpisreceivingpowerand
tatitturns.Ceckiftereisairtrappedin
tepumpousing–seepumpmanual.
Tepumpissetattoolowspeedof
rotation.
Settepumpatigerspeedofrotation.
Pressuredrop–tepressuredropon
teradiatorcircuitsowslowertan
recommendedoperatingpressure.
Fillwaterontesystemandceckte
functioningoftepressureexpansion
vesselifrequired.
Airpocketsintesystem.Ventteinstallationtorougly.
Limitingoftereturntemperatureadjusted
toolow.
Adjustaccordingtoinstructions.
Defectiveradiatorvalves.Ceck–replace.
Uneveneatdistributioninbuilding
becauseofincorrectlysetbalancingvalves,
orbecauseterearenobalancingvalves.
Adjust/installbalancingvalves.
Diameterofpipetosubstationtoosmallor
brancpipetoolong.
Ceckpipedimensions.
Uneveneatdistribution.Airpocketsintesystem.Ventteinstallationtorougly.
DHsupplytemperaturetooig.Wrongsettingoftermostatorof
automaticcontrols,ifany.
Adjustautomaticcontrols,–see
instructionsforautomaticcontrols.
Defectivecontroller.Tecontrollerdoes
notreactasitsouldaccordingtote
instructions.
Callautomaticcontrolsmanufactureror
replaceteregulator.
Defectivesensoronself-actingtermostat.Replacetermostat–orsensoronly.
DHsupplytemperaturetoolow.Wrongsettingofautomaticcontrols,ifany.Adjustautomaticcontrols–seeinstructions
forautomaticcontrols.
Defectivecontroller.Tecontrollerdoes
notreactasitsouldaccordingtote
instructions.
Callinautomaticcontrolsmanufactureror
replacecontroller.
Defectivesensoronself-actingtermostat.Replacetermostat–orsensoronly.
Wrongplacement/fittingofoutdoor
temperaturesensor.
Adjustlocationofoutdoortemperature
sensor.
Strainerclogged.Cleangate/strainer.
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TooigDHreturntemperature.Toosmalleatingsurface/toosmall
radiatorscomparedtotetotaleating
requirementoftebuilding.
Increasetotaleatingsurface.
Poorutilizationofexistingeatingsurface.
Defectivesensoronself-actingtermostat.
Makesureteeatisdistributedevenly
acrosstefulleatingsurface–openall
radiatorsandkeepteradiatorsinte
systemfromeatingupattebottom.It
isextremelyimportanttokeeptesupply
temperaturetoteradiatorsaslowas
possible,wilemaintainingareasonable
levelofcomfort.
Tesystemissinglepipeloop.Tesystemsouldfeatureelectronic
controlsaswellasreturnsensors.
Pumppressuretooig.Adjustpumptoalowerlevel.
Airinsystem.Venttesystem.
Defectiveorincorrectlysetradiatorvalve(s).
Singlepipeloopsystemsrequirespecial
one-piperadiatorvalves.
Ceck–set/replace.
Dirtintemotorizedvalveorinte
differentialpressurecontroller.
Ceck–cleanout.
Defectivemotorizedvalve,sensoror
automaticcontroller.
Ceck–replace.
Electroniccontrollernotadjustedcorrectly.Adjustaccordingtoinstructions.
Noiseinsystem.Pumppressuretooig.Adjustpumptoalowerlevel.
Heatloadtooig.Defectivemotorizedvalve,sensoror
electroniccontroller.
Ceck–replace.
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