Specifications

TroubleshootingGuide
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10|Page
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• Theflowadjustmentvalvecouldbeobstructedduetohardwaterscaleordebris,causinglower
thanexpectedwaterflow.Verifywaterflowwithagraduatedcontainerorwiththeremote
temperaturecontroller,ifoneisinstalled.
• Theoutputthermistorcouldbecompromised.Thiscomponentmaybecheckedby
enteringthe
DiagnosticsModeonaremotecontroller,ifoneisinstalled.Turnpowerofftotheunit andrun
coldwaterthroughit;checktoseeiftheinletandoutlettemperaturesreadthesameonthe
remote.Forinstructionsonhowtodothis,refertotheMaintena nce 
Sheet,packagedwith
everytanklesswaterheaterandlocatedbehindthefrontpaneloftheunit.
TEMPERATUREFLUCTUATESWH ENAFIXTUREISOPENED
• MakesuretheunitisinstalledproperlyusingtheProperInstallationsection(p.6)ofthisguide.
• Testwhethertheproblemiswithintheunitorexternaltotheunit(i.e.plumbingsystem)by
attemptingtorunhotwaterlocallythroughthePRV.
o Doestheheaterigniteand
remainrunningproperly?Ordoestheheatershutdowninto
anerrorcode?
• Plumbingconnections
o Checkforacrossconnection(p.24).
o Problemswitharecirculationsystem:
 Checkthatacheckvalveis installedbetweenthepumpdischargeandthe
connectiontothecoldwatersupply.
 Checktoseeifthepumpisoperatingproperly.
 Checkforaircavitation.Thepumpwillbeveryhotorchattering.
 Checkthedirectional indicatoronthepumpflange.
 Checkthesizingofthepump–aminimumflowof2gpmisrequired.
• Checkgas
supply
o VerifythegassupplylinesaresizedforthemaximumBtu/hdemand,asindicatedinthe
ProperInstallationsection(p.6)ofthisguide.Ifthegassupplylineissharedwithother
appliances,itshouldbesizedtoaccountforthoseappliancesaswell.Theheaterwill
stilltrytorunifthegassupplyisundersizedandhasnowayofdirectlydeterminingif
thereisnotenoughgas.
o ForLPmodels,theremaynotbeenoughgasleftinthepropanetank.
o Verifythatthesupplygaspressureiswithinspecification,not onlywhen
theheaterisin
standby,butwhiletheheaterisrunningonmaximumfireaswell.
o Thegassupplypressuremaybetoolow.Thismaybecausedbyamalfunctioninggas
supplyregulator.
• Venting
o Verifythattheexhaustventingisinstalledtomanufacturer’sspecification.
o Verify
thattheventrundoesnotexceedthemaximumlimit(50ft.)
• Thefilteroncoldwaterinletshouldbeclean;lookforsignsofhardwaterscaling.
• Ifthecleartubefromtheproportionalgasvalvetothebottomofthecombustionchamberis
disconnected,fluctuations intemperatureand/orverylowflowtothefixturesmayoccur.
• Onwellsystemsorevenonsomecitywatersystems,waterpressurefluctuations(especiallyon
lowflow)of8to10psiwillresultinflowratefluctuations,whichwillinturnresultinminor
temperaturefluctuations.
• Flowsensor
orwatercontrolvalvemaybecompromised.Contactthetechnicalservice
department.
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