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INSTALLATION INSTRUCTIONS
VentingforDirect-VentWaterHeater
DANGER:Failuretoproperlyventthewater Acceptablematerialsorequivalent:
PVC(Schedule40,ASTMD-1785)
Venting
heatertotheoutdoorsasoutlinedinthisVenting
sectionwillresultindeathorseriouspersonalinjury.
Toavoidtheriskoffire,explosion,orasphyxiation
fromcarbonmonoxide,NEVERoperatethewater
heaterunlessitisproperlyventedandhasadequate
airsupplyforproperoperationasoutlinedinthis
Ventingsection.Thiswaterheatermusthaveair
supplyconnectedandterminatedtotheoutdoors.
WARNING:
Refertopage29forrequiredclearancesto
combustiblematerials.Improperclearancescancause
explosionorfireresultingindeath,personalinjury,
and/orproductdamage.
CAUTIONS:
•Checktomakesurefluegasesdonotrecirculateinto
theairintaketerminalwhenusingdirectventing.Ifthe
waterheaterishavingserviceissues,fluerecirculation
maybeacontributingfactor.
•Evenwhentheminimumventterminalseparation
distancesarefollowed,recirculationmaystilloccur
dependinguponthelocationoutsidethebuilding,
thedistancefromotherbuildings,proximityto
corners,weatherconditions,windpatterns,and
snowdepth.
•Periodicallychecktomakesurethatflue
recirculationisnotoccurring.Signsoffluegas
recirculationincludefrostedorfrozenintake
terminalsandcondensateintheintaketerminaland
ventingsystem.
•Correctiontofluerecirculationmayinvolveangling
theintakeawayfromtheexhaustterminaland
increasingthedistancebetweenthem.Checkto
besuretheintakeandexhaustterminalsarenot
obstructed,especiallyduringperiodsofbelowfreezingweather.
VentingRequirements
The installationofventingmustcomplywithnational
codes,localcodes,andtheventmanufacturer’s
instructions.
Theventexhaustandairintakemustterminateoutside
asdescribedintheseinstructions.DONOTventthis
waterheaterthroughachimney.Itmustbevented
separatelyfromallotherappliances.
NOTICE:
Theunitcanbeventedusingonlythe
followingapprovedventpipematerial.
Useonly2-or3-inchdiameterpipe.Refertolocalcodes
forrestrictionsontheuseofPVC,CPVC,orABSpipe
andfittings.Allexhaustventingmaterialsforproduct
installedinCanadamustmeetULC-S636.
CPVC(Schedule40,ASTMF-441)
ABS(Schedule40,ASTMD-2661)
(notpermittedforexhaustventinCanada)
Thefittings,otherthantheVENTTERMINAL,
shouldbeequivalenttothefollowing:
PVC(Schedule40DWV,ASTMD-2665)
CPVC(Schedule40DWV,ASTMF-438)
ABS(Schedule40DWV,ASTMD-2661)
(NotpermittedinCanada)
CategoryIIIStainlessSteel(Propertransitionpart
required)
DONOTUSESchedule20,CellCore,DrainPipe,
Galvanized,Aluminum,orB-Vent.
RecommendedVentLengths
Beforestartingtheventinstallation,carefulplanning
shouldbegiventotheroutingandterminationofthe
ventpipes.Thelengthoftheventpipes(inletand
outlet)shouldbekepttoaminimum.Also,seepages
37–38and44forventterminalplacement.Refertothe
maximumandminimumventlengthchartsforthepipe
sizesthatcanbeusedandthetotalequivalentlength
ofpipethatcanbeused.Donotexceedequivalent
lengthofpipeinmaximumventlengthchart.
MaximumVentLength(intake/outlet):
Numberof
90°Elbows
1
5.0ft.(1.5m)
38.0ft.(11.6m)
2
3.5ft.(1.0m)
36.5ft.(11.1m)
3
2.0ft.(0.6m)
35.0ft.(10.6m)
4
Notavailable
33.5ft.(10.2m)
5
Notavailable
32.0ft.(9.8m)
6
Notavailable
30.5ft.(9.3m)
Thesystemwillnotoperateifthereisexcessive
restriction(pressuredrop)intheventingsystem.Use
thechartabovetocalculatethemaximumpiperun
lengthwiththerequirednumberofelbows(e.g.,a
maximum38ft.[12m]of3"ventpipemaybeused
providedthereisonlyone90°elbowinthesystem).
A90°elbowisequivalentto1ft.6in.(0.5m)of
straightpipe.A45°elbowisequivalentto9”(0.25m)
ofstraightpipe.
Theventterminationdoesnotcountaspartofthe
straightpipeequivalentwhendeterminingthetotal
ventlength.
MinimumVentLength:
Numberof
90°Elbows
1
34
MaximumLength MaximumLength
of2"StraightPipe of3"StraightPipe
MinimumLength MinimumLength
of2"StraightPipe of3"StraightPipe
1.0ft.(0.3m)
1.0ft.(0.3m)
INSTALLATION INSTRUCTIONS
NOTICE:Touse2-inchventpipe,areducing
adapterorbushingwillberequired.
WARNING:
TouseCategoryIIIStainlessSteel,apropertransition
partwillberequiredtopreventfluegasfromleaking.
NOTICES:
•Itisrecommendedthattheairintakeandexhaust
pipeshavea1/4"perfootdownwardslopetoward
theoutdoors.
•Maintaintheproperclearancebetweentheventpipe
andcombustibleornoncombustiblematerialsare
describedonpages28,29.
•Azeroclearance0in.(0cm)isallowedbetweenthe
airintakepipesandcombustiblematerial.
•Usepropersupportfortheventandairintakepipes.
•Itisrecommendedthesupportmethodusedisolates
theventpipefromfloorjoistsorotherstructural
members.Thishelpspreventtransmissionofnoise
andvibration.
•Donotsupport,pin,orotherwisesecuretheventing
systeminawaythatrestrictsthenormalthermal
expansionandcontractionofthechosenventing
material.
Seepage36foradditionalrequirementsforthe
CommonwealthofMassachusetts.
Stresslevelsinthepipeandfittingscanbe
significantlyincreasedbyimproperinstallation.If
rigidpipeclampsareusedtoholdthepipeinplace,
orifthepipecannotmovefreelythroughawall
penetration,thepipemaybedirectlystressed,orhigh
thermalstressesmaybeformedwhenthepipeheats
upandexpands.Installaccordinglytominimizesuch
stresses.
PreexistingVentingNotes:
Ifthewaterheaterisbeinginstalledasareplacement
foranexistingwaterheater,athoroughinspection
oftheexistingventingandairintakesystemmustbe
performedpriortoanyinstallationwork.Verifythatthe
correctmaterials,ventlengths,andterminallocations
asdescribedinthismanualhavebeenmet.Carefully
inspecttheentireventingandairintakesystemforany
signsofcracksorfractures,particularlyatthejoints
betweenelbowsorotherfittingsandthestraightruns
ofventpipe.Checkthesystemforsignsofsaggingor
otherstressesinthejointsasaresultofmisalignment
35
Venting
Dependingonthesizeofpipethatischosenfor
ventingthewaterheater,itmightbenecessarytouse
afittingforsteppingdowninpipesize,toconnectto
thewaterheater.
Allintakeandexhaustventingcomponentsmusthave
thesamediametersize.Donotuseadifferentsizeon
theintakeandexhaustventing.
Theunitmaybeventedhorizontallythrougha
wallorverticallythroughtheroof.Piperunsmust
beadequatelysupportedalongbothverticaland
horizontalruns.Maximumunsupportedspanis
recommendedtobenomorethan4feet(1.2m).It
isimperativethatthefirsthangerbelocatedonthe
horizontalrunsimmediatelyadjacenttothefirst
90-degreeelbowfromtheverticalrise.Onlyuse
supportisolationhangingbands.DONOTusewireto
supportpiperuns.
ofanycomponentsinthesystem.Ifanyofthese
conditionsarefound,theymustbecorrectedin
accordancewiththeventinginstructionsinthismanual
beforecompletingtheinstallationandputtingthewater
heaterintoservice.