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3.FlameDetectionSensor 4.GasLeakDetector
1.Closethegasshutovalve.
2.Turnthepowero.
3.Byusingahandscrewdriver,remove4screwsof
thefrontcover.
4.Disconnectalltheelectricalconnectiontothe
circuitboard.
5.Loosentwoscrewstoremovethecircuitboard.
6.Replacethecircuitboardwithnewcomponent.
7.Assembleinthereverseorderasthepartwas
removed.
8.Assembleconnectorsoncircuitboard.
9.Openthegasshutovalve
10.Turnthepoweron.
11.Turnbackthewatervalveintheopeningdirection.
12.Testoperation.(Pleaserefertopage81for
combustioncharacteristicstest.)
MaincomponentsReplacementInstructions
1.Closethegasshutovalve.
2.Turnthepowero.
3.Disconnecttheelectricalconnectiontotheame
detectionsensor.
(Pushandholdthebuttononthebacksideofthe
connectiontoremove.)
4.Rotateamedetectionsensor45degrees
clockwiseandpullforward.
5.Replaceamedetectionsensorwithnew
component.
6.Assembleinthereverseorderasthepartwas
removed.
7.Openthegasshutovalve.
8.Turnthepoweron.
9.Turntheunitonandensureproperoperation.
NOTE
1.Checkxedconditionofthepart.
Chapter5ReplacementInstructions