A.O. Smith 310 - Page 16

TroubleshootingGuide
16|Page
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ERRORCODE391[510(T‐D2)],TWOFLASHES/39[110(T‐KJR2),310(T‐K4) ]
AIR‐FUELRATIORODFAILURE
1) Checkthatthewireconnectionsaresecureandfreeof
burnsorcuts.
2) Checkthattheclearplastictubeconnectingthe
proportionalgasvalvetothecombustionchamber is 
attached.
3) CleantheAFR(p.25).
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ERRORCODE441[510(T‐D2)]
FLOWSENSOR
PartofanEasy‐Linksystem(510(T‐D2)only),themasterunit
signaledforanadditionalheatertoactivateanditdidnot.
1) Verifythatwaterisbeingsuppliedtotheheaterinerror.
2) Verifythatthewiresareconnectedtothecomputerboard.
3) Checktheinlet
filterforanydebris.Seep.21.
4) Checktheflowsensorfordebris.
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ERRORCODE510[510(T‐D2)],SIXFLASHES/51[110(T‐
KJR2),310(T‐K4) ]
ABNORMALGASVALVES
Drivingcircuitfaultforthemainorsolenoidgasvalves.
1) Ifthehotwaterisshutoff,butflames
arestillvisiblethroughthesightglass,
immediatelyshutoffgasandpowerto
theunitandcontacttheTechnical
ServiceDepartment.
2) Checkthewireconnectionstothegas
valve
assemblyforburnsorcuts.
3) Iftheunitwasrecentlyrebuilt,make
surethateachgasvalvewireisplugged
intotheproperplace.
4) Verifythatthesupplygaspressureis
withinthespecifiedlimits.Toohighof
aninletgaspressuremaycausethe
maingasvalvetojamorcouldbe
damaged.
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ERRORCODESIXFLASHES/55[110(T‐KJR2),310(T‐K4)]
ABNORMALSOLE NOIDGASVALVE
Drivingcircuitfaultforthesolenoidgasvalve.
1) Ifthehotwaterisshutoff,butflamesarestillvisiblethroughtheburnersightwindow,immediately
shutoffgasandpowertotheunitandcontacttheTechnicalServiceDepartment.
2) Checkthewireconnectionstothegasvalveassembly
forburnsorcuts.
3) Iftheunitwasrecentlyrebuilt,makesurethateachgasvalvewireispluggedintotheproperplace.
4) Verifythatthesupplygaspressureiswithinthespecifiedlimits.Toohighofaninletgaspressure
maycausethemaingasvalvetojamorcouldbe
damaged.
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Figure10
Figure11
Figure12