ELECTRICALOPERATIONHAZARD
Failuretofollowthiswarningcouldresultinpersonalinjury
ordeath.
Blowerdoorswitchopens115-vpowerto control.No
componentoperationcanoccurunlessswitchis closed.
Cautionmustbetakenwhenmanuallyclosingthisswitchfor
servicepurposes.
16.Downfloworhorizontalfurnaceswithventpipethrough
furnaceonly:
a.Installandconnectshortpieceofventpipeinsidefurnace
toexistingvent.
b.Connectventconnectortoventelbow.
17.Turnonelectricalsupply.Manuallycloseblowerdoor
switch.Useapieceoftapetoholdswitchclosed.Checkfor
properrotationandspeedchangesbetweenheatingand
coolingbyjumperingRtoGandRtoY/Y2onfurnace
controlthermostatterminals.If outdoortemperatureisbe-
low70°F,turnoffcircuitbreakertooutdoorunitbefore
runningfurnaceinthecoolingcycle.Turnoutdoorcircuit
breakeronaftercompletingcoolingcycle.(SeeFig.35.)
NOTE:If R-W/Wlthermostatterminalsarejumperedatthetime
blowerdoorswitchisclosed,blowerwillrunfor90secbefore
beginningaheatingcycle.
a.Performcomponentself-testasshownatthebottomofthe
SERVICElabel,locatedonthecontroldoor.
b.Verifyblowerisrotatinginthecorrectdirection
18.If furnaceis operatingproperly,RELEASEBLOWER
DOORSWITCH.Removeanyjumpersorreconnectany
disconnectedthermostatleads.Replaceblowerdoor.
19.Turnongassupplyandcyclefurnacethroughonecomplete
heatingcycle.Verifythefurnacetemperatureriseasshown
inAdjustmentsSection.Adjusttemperatureriseasshownin
AdjustmentsSection.
CleaningBurnersandFlameSensor
Thefollowingitemsmustbeperformedbyaqualifiedservice
technician.If theburnersdevelopanaccumulationoflightdirtor
dust,theymaybecleanedbyusingthefollowingprocedure:
NOTE:Useaback-upwrenchonthegasvalvetopreventthe
valvefromrotatingonthemanifoldordamagingthemountingto
theburnerassembly.
ELECTRICALSHOCKANDFIREHAZARD
Failuretofollowthiswarningcouldresultinpersonaliniury,
death,and/orpropertydamage.
Turnoffthegasandelectricalsuppliestothefurnaceand
installlockouttagbeforeperforminganymaintenanceor
service.Followtheoperatinginstructionsonthelabel
attachedtothefurnace.
RefertoFig.62.
1.Disconnectpoweratexternaldisconnect,fuseorcircuit
breaker.
2.Turnoffgasatexternalshut-offorgasmeter.
3.Removecontroldoorandsetaside.
4.TurnelectricswitchongasvalvetoOFF.
5.Disconnectthegaspipefromgasvalveandremovepipe
fromthefurnacecasing.
6.Removeindividualwiresfromterminalsongasvalve.
7.DisconnectHotSurfaceIgniter(HSI)wiresfromHSI.
8.DisconnectFlameSensorwirefromFlameSensor.
9.Supportthemanifoldandremovethe4screwsthatsecure
themanifoldassemblytotheburnerassemblyandsetaside.
Notethelocationofthegreen/yellowwireandgroundter-
minal.
10.Inspecttheorificesinthemanifoldassemblyforblockages
orobstructions.Removeorificeandcleanorreplaceorifice.
11.Removethefourscrewsthatattachthetopplateofthecas-
ingtothefurnace.
12.Raisetopplateupslightlyandpropit upwithasmallpiece
ofwoodorfoldedcardboard.
13.Supporttheburnerassemblyandremovethescrewsthatat-
tachtheburnerassemblytotheheatexchangercellpanel.
14.Removewiresfrombothrolloutswitches.
15.Slideone-pieceburneroutofslotsonsidesofburneras-
sembly.
16.Removetheflamesensorfromtheburnerassembly.
17.(Optional)RemovetheHotSurfaceIgniter(HSI)and
bracketfromtheburnerassembly.
18.Checkigniterresistance.Nominalresistanceis40to70
ohmsatroomtemperatureandisstableoverthelifeofthe
igniter.
19.Cleanburnerwithabrushandavacuum.
20.Cleantheflamesensorwithfinesteelwool(0000grade).
Donotusesandpaperoremerycloth.
Toreinstallburnerassembly:
1.InstalltheHotSurfaceIgniter(HSI)andbracketinburner
assembly.
2.Installflamesensoronburner.
3.Aligntheedgesoftheone-pieceburnerwiththeslotsinthe
burnerassemblyandslidetheburnersforwarduntiltheyare
fullyseatedintheburnerassembly.
4.Aligntheorificesinthemanifoldassemblywiththesupport
ringsontheendoftheburner.
5.Inserttheorificesinthesupportringsoftheburners.
NOTE:If manifolddoesnotfitflushagainsttheburner,donot
forcethemanifoldontheburnerassembly.Theburnersarenot
fullyseatedforwardintheburnerassembly.Removethemanifold
andcheckburnerpositioningin theburnerassemblyassembly
beforere-installingthemanifold.
6.Attachthegreen/yellowwireandgroundterminaltooneof
themanifoldmountingscrews.
7.Installtheremainingmanifoldmountingscrews.
8.Checktheigniteralignment.SeeFig.56,58and62.
9.Attachthewirestotheroll-outswitches.
10.Aligntheburnerassemblywiththeopeningsintheprimary
cellinletpanelandattachtheburnerassemblytothecell
panel.
11.Connectthewirefortheflamesensor.
12.ConnectthewirefortheHotSurfaceIgniter.
NOTE:Usepropane-resistantpipedopetopreventleaks.Donot
useTeflontape.
13.Installthegaspipetothegasvalve.
FIREOR'EXPLOSIONHAZARD
Failuretofollowthiswarningcouldresultin personal
iniury,death,and/orpropertydamage.
Neverpurgeagaslineintoacombustionchamber.Never
testforgasleakswithanopenflame.Useacommercially
availablesoapsolutionmadespecificallyforthedetection
ofleakstocheckallconnections.Afireorexplosionmay
resultcausingpropertydamage,personaliniuryorlossof
line.
14.Checkforgasleakswithacommerciallyavailablesoap
solutionmadespecificallyforthedetectionofleaks.
75
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