A.O. Smith 310 - Purge the Gas Line of Air

TroubleshootingGuide
22|Page
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5) Slowlyre‐openthemanualgasvalve.Checktoseethattherearenogasleaks.
6) Opensomeofthefixturesthatusethehighestflowratetoactivate.
7) Checktheinletgaspressure.Appropriatepressuresarelistedinthespecificationpageat
thefrontofthismanual.
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PURGETHEGA SLINEOFAIR:
1) Theunitshouldnotberunningduringthisprocedure.Turnoffpowertotheunit.
2) Turnthegasvalvetotheoffposition(perpendiculartothegasline).
3) Loosenthegaslineontheunitsideofthegasvalve(ataflarefittingorunion).
4) Next
openthegasvalveveryslightlyuntilyoucansmellgasbywaftingtheairtowardsyour
nose.Thismeansanyairpreviouslyinthegaslinehasbeenremovedandonlygasremains.
5) Turngasbackoffandre‐tightengasline.
6) Turngasbackonand
checkforleaks.Spraywater&dishsoapmixtureontofittings.No
bubblesmeanstherearenoleaks.
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CHECKINGMANIFOLDGASPRESSURE:
1) Ensuretheunitisnotinoperation.
2) Removethescrewoffthemanifoldport.
3) Connectamanometertothemanifoldportusing
atube(Figure1).Ensurethatthisconnectionis
secureenoughtopreventgasleak.
4) Runwaterthroughtheunittoactivateits
operation.It
issuggestedthatalargeamountof
flowisdrawninordertopreventoverheating
duringmaxburn.Ifpresenceofagasleakis
detected,immediatelyshutofftheunitand
inspectthetube/manifoldconnection;otherwise,
proceedontothenextstep.
5) Tocheckthemanifoldgaspressureduring
maximumcombustion,pressandholdthe“MAX”
buttononthecomputerboard.Tocheckthemanifoldpressureduringminimum
combustion,pressandholdthe“MIN”buttononthecomputerboard.Thedesired
pressuresarelistedinthespecificationtableatthebeginningofthismanual.
6) Ifthemanifold
pressuresdonotmatchupwiththoselisted, adjustthemanifoldpressure
(seethefollowingprocedure).
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Figure19