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13.3ServicingInternalIntegrity
SafetyNote:Beforeremovingthefrontcover;thecorrectshutdownsequencemustbefollowedforyourownsafety.
Beforeservicing,ensurethattheboileriscoolwiththeengineheadbelow120°Cotherwisethereisariskof
electricshockevenwiththesuppliesdisconnected.
TheheadtemperaturemaybeaccessedviatheTHINKController.
PresstheMENUButton.TurntheSelectorButtontohighlight'Information'.
PresstheButtontoselect.TurnSelectorButtonuntil'headtempactualvalue'isshown.
Ensurethatboththegasandelectricalsuppliestotheapplianceareisolatedwaitaminimumof6minutes30seconds
beforeanyworkisstartedagainthereisariskofelectricshockevenwiththesuppliesdisconnected.
NOTE:Beforeundertakinganyserviceworkthatentailstheremovalandreplacementofparts,ensurethatthecenter
transitbracketisrefittedtoprotecttheenginehead(seeFig.48).
Thisbracketmustthenberemovedbeforerunningtheengine.
1.Removetheplasticfaciaonthefrontoftheappliancewhichisheldonbytwomagnets(Fig.51).
2.Removethetwoscrewsandthefrontcasebypullingforwardatthebottomedgeandthenliftingclearoftheengagementatthetopoftheappliance(Fig.51).
3.Undothefourscrewsfromthebottomcoverandremovethecover(Fig.51).
4.Removethetwoscrewsonthefrontofthecontroltraytogainaccesstothecontroltrayarea(Fig.52).
5.Inspecttheunitforanysignsofwaterdamageandrectifyanyleaks.
6.Generallychecktheconditionsofthewiringoftheapplianceandtheexternalwiringforandloose/poorconnectionsandremakeifnecessary.
7.Inspecttheconditionofthecondensetrapforsignsofdebrisandpossibleblockage.Ifnecessaryremovetheserviceplug,drainandcleanthecompartment.Replacethe
plug,reassemblethecaseandcheckforcorrectoperationwhentheapplianceisrunning.
8.Checkandcleanthemagneticfilterifitisoftheserviceabletype,otherwisereplacethecartridge.Ifitobservedthatthereisexcessiveamountsofcorrosionproduct
blackresidue/sludgechecktheinhibitorlevelinthesystemandtopupwithinhibitorsolutionasrequired.
Fig.51&Fig.52
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13.4ServicingCombustionandRateChecks
1.Performcombustionandratechecksbyusingthechimneysweepmodetoforceeachburnerintomaximumrate(seesection15.0CombustionChecks).Combustion
readingofCO2~8.79.3andCOlessthan100ppmareacceptableforbothburners.MeasuretheCO/CO2ratio.Thisvalvemustbelessthan0.004.
2.Seteachburnerseparatelytoaminimumandcheckthattheburnerstayslitwithcleancombustion.
3.IfthereisaproblemwiththerateorcombustionseeSection15.2.
4.Ifthereisaproblemwiththeignition,thefollowingservicingshouldbecarriedout.
SeeSAFETYNOTESection13.3EngineIgnitionandFlameSensingElectrodes(Fig.53)
1.Detachtheignitionandflamesenseleadsfromthewiringharnessnotingtheirpositions.
2.Undothelongnuts(7mmspanner)retainingtheengineignitionandflamesenseelectrodes.
3.Carefullywithdrawtheelectrodesfromtheengine.