Rinnai REU?VC2528FFUD?US User manual

DirectVentTanklessWaterHeater
InstallaonandOperaonManual
—Donotstoreorusegasolineorotherflammablevaporsandliquidsinthevicinityofthisoranyother
appliance.
—WHATTODOIFYOUSMELLGAS
• Donottrytolightanyappliance.
• Donottouchanyelectricalswitch;donotuseanyphoneinyourbuilding.
• Immediatelycallyourgassupplierfromaneighbor’sphone.Followthegassupplier’sinstrucons.
• Ifyoucannotreachyourgassupplier,callthefiredepartment.
—Installaonandservicemustbeperformedbyalicensedprofessional.
Thisenremanualmustbelefortheconsumer.Theconsumermustreadand
refertothismanualforproperoperaonandtomaintainthewaterheater.
Iftheinformaonintheseinstruconsisnotfollowedexactly,afireorexplosion
mayresultcausingpropertydamage,personalinjuryordeath.
WARNING
READALLOFTHEINSTRUCTIONSTHOROUGHLYBEFOREINSTALLINGOROPERATINGTHISWATERHEATER.
Thismanualprovidesinformaonontheinstallaon,operaon,andmaintenanceofthewaterheater.Forproper
operaonandsafety,itisimportanttofollowtheinstruconsandadheretothesafetyprecauons.
Alicensedprofessionalmustinstallthewaterheateraccordingtotheexactinstruconsonpages4‐30.
Theconsumermustreadtheenremanualtoproperlyoperatethewaterheaterandtohaveregularmaintenance
performed.
ANSZ21.10.3●CSA4.3
FORINDOORAPPLICATIONSONLY
RL75i.....................REU‐VC2528FFUD‐US
RL94i.....................REU‐VC2837FFUD‐US
FOROUTDOORAPPLICATIONSONLY
RL75e....................REU‐VC2528WD‐US
RL94e....................REU‐VC2837WD‐US

2VCSeriesManual
TableofContents
Thisisthesafetyalertsymbol.Thissymbolalertsyoutopotenalhazardsthatcankillorhurtyou
andothers.
Indicatesanimminentlyhazardoussituaonwhich,ifnotavoided,willresultindeathor
seriousinjury.
Indicatesapotenallyhazardoussituaonwhich,ifnotavoided,couldresultindeathor
seriousinjury.
Indicatesapotenallyhazardoussituaonwhich,ifnotavoided,couldresultinminoror
moderateinjury.Itmayalsobeusedtoalertagainstunsafepracces.
DANGER
CAUTION
WARNING
TableofContents.....................................................2
SafetyBehaviorsandPraccesforthe
ConsumerandInstaller............................................3
InstallaonInstrucons
(forthelicensedprofessional)..............................4
PrepareforInstallaon......................................5
DetermineInstallaonLocaon........................6
ChecklisttoDetermineInstallaonLocaon...12
MounttoWall..................................................12
RemovetheFrontPanel..................................12
InstallaonofVenng(indoormodelsonly)...13
Condensate(indoormodelsonly)...................15
ChecklistforVenngandCondensate
(indoormodelsonly)........................................15
InstallaonofPlumbing...................................16
ChecklistforPlumbing.....................................19
InstallaonofGasSupply................................19
ConnectElectricity...........................................21
AdjustforHighAltude...................................21
AdjustforVentLength(indoormodelsonly)..21
ChecklistforGasandElectricity......................21
InstallaonofTemperatureController...........22
FinalChecklist..................................................24
TechnicalData........................................................25
Specificaons...................................................25
Dimensions......................................................26
PressureDropandWaterFlowCurves............27
LadderDiagram................................................28
RecirculaonMode(RL94Models).................29
OperaonInstrucons........................................31
ConsumerOperaonGuidelinesforthe
SafeOperaonofyourWaterHeater..............32
HowtoUsetheTemperatureController.........33
HowtoSettheTemperature...........................34
DiagnoscCodes..............................................36
RequiredMaintenance....................................39
FlushingtheHeatExchanger.....................41
ManualDrainingoftheWaterHeater......42
StateRegulaons....................................................43
ReplacementParts.................................................44
ConsumerWarranty...............................................45
FrenchVersion........................................................48
ImportantSafetyInformaon
SafetyDefinions
NOTICE:Rinnaisomemessharescustomercontactinformaonwithbusinessesthatwebelieveprovide
productsorservicesthatmaybeusefultoyou.Byprovidingthisinformaon,youagreethatwecan
shareyourcontactinformaonforthispurpose.Ifyouprefernottohaveyourinformaonsharedwith
thesebusinesses,pleasecontactcustomerserviceandasknottohaveyourinformaonshared.We
willhowever,connuetocontactyouwithinformaonrelevanttotheproduct(s)youregisteredand/
oryouaccountwithus.
IfyouhaveanyquesonsorfeelthatthemanualisincompletecontactRinnaiat1‐800‐621‐9419.

VCSeriesManual3
CAUTION
• BURNHAZARD.Hotexhaustandventmaycause
seriousburns.Keepawayfromwaterheaterunit.
Keepsmallchildrenandanimalsawayfromunit.
• Hotwateroutletpipesleavingtheunitcanbehot
totouch.Inresidenalapplicaons,insulaon
mustbeusedforhotwaterpipesbelow36”dueto
burnrisktochildren.
Californialawrequiresthisnocetobeprovided:
CaliforniaProposion65listschemicalsubstancesknowntothestatetocausecancer,birthdefects,death,
seriousillnessorotherreproducveharm.Thisproductmaycontainsuchsubstances,betheiroriginfromfuel
combuson(gas,oil)orcomponentsoftheproductitself.
SafetyBehaviorsandPraccesfortheConsumerandInstaller
• Beforeoperang,smellallaroundtheappliance
areaforgas.Besuretosmellnexttothefloor
becausesomegasisheavierthanairandwillsele
onthefloor.
• Keeptheareaaroundtheapplianceclearandfree
fromcombusblematerials,gasoline,andother
flammablevaporsandliquids.
• Combusbleconstruconreferstoadjacentwalls
andceilingandshouldnotbeconfusedwith
combusbleorflammableproductsandmaterials.
Combusbleand/orflammableproductsand
materialsshouldneverbestoredinthevicinityof
thisoranygasappliance.
• Alwayscheckthewatertemperaturebefore
enteringashowerorbath.
• Toprotectyourselffromharm,beforeperforming
maintenance:
◊ Turnofftheelectricalpowersupplyby
unpluggingthepowercordorbyturningoffthe
electricityatthecircuitbreaker.(The
temperaturecontrollerdoesnotcontrolthe
electricalpower.)
◊ Turnoffthegasatthemanualgasvalve,usually
locatedimmediatelybelowthewaterheater.
◊ Turnofftheincomingwatersupply.Thiscanbe
doneattheisolaonvalveimmediatelybelow
thewaterheaterorbyturningoffthewater
supplytothebuilding.
WARNING

• Useonlyyourhandtopushinorturnthegas
controlknob.Neverusetools.Iftheknobwillnot
pushinorturnbyhand,donottrytorepairit;calla
licensedprofessional.Forceoraemptedrepair
mayresultinafireorexplosion.
• Donotusethisapplianceifanyparthasbeenunder
water.Immediatelycallalicensedprofessionalto
inspecttheapplianceandtoreplaceanypartofthe
controlsystemandanygascontrolwhichhasbeen
underwater.
• Donotusesubstutematerials.Useonlyparts
cerfiedwiththeappliance.
• Shouldoverheangoccurorthegassupplyfailto
shutoff,turnoffthemanualgascontrolvalvetothe
appliance.
• DonotadjusttheDIPswitchunlessspecifically
instructedtodoso.
• Donotuseanextensioncordoranadapterplug
withthisappliance.
• Anyalteraontotheapplianceoritscontrolscanbe
dangerousandwillvoidthewarranty.

4VCSeriesManual
Alicensedprofessionalmustinstalltheappliance,
inspectit,andleaktestitbeforeuse.Thewarranty
willbevoidedduetoimproperinstallaon.
Theinstallershouldhaveskillssuchas:
• gassizing
• connecnggaslines,waterlines,valves,
electricity,
• knowledgeofapplicablenaonal,state,and
localcodes.
• installingvenngthroughawallorroof
Ifyoulacktheseskillscontactalicensedprofessional.
InstallaonInstrucons
InstallaonSteps
PrepareforInstallaon......................................5
DetermineInstallaonLocaon........................6
ChecklisttoDetermineInstallaonLocaon...12
MounttoWall..................................................12
RemovetheFrontPanel..................................12
InstallaonofVenng(indoormodelsonly)...13
Condensate(indoormodelsonly)
....................15
ChecklistforVenngandCondensate
(indoormodelsonly)........................................15
InstallaonofPlumbing...................................16
ChecklistforPlumbing.....................................19
InstallaonofGasSupply................................19
ConnectElectricity...........................................21
AdjustforHighAltude...................................21
AdjustforVentLength(indoormodelsonly)..21
ChecklistforGasandElectricity.......................21
InstallaonofTemperatureController............22
FinalChecklist..................................................24
GeneralInstruconsInstallerQualificaons
DONOT
• DonotinstalltheRL75iortheRL94ioutdoors.
• DonotinstalltheRL75eortheRL94eindoors.
• Donotinstalltheapplianceinanareawherewater
leakageoftheunitorconneconswillresultin
damagetotheareaadjacenttotheapplianceorto
lowerfloorsofthestructure.Whensuchlocaons
cannotbeavoided,itisrecommendedthata
suitabledrainpan,adequatelydrained,beinstalled
undertheappliance.Thepanmustnotrestrict
combusonairflow.
• Donotobstructtheflowofcombusonand
venlaonair.Combusonairshallnotbe
suppliedfromoccupiedspaces.
• Donotusethisapplianceinanapplicaonsuchas
apoolorspaheaterthatuseschemicallytreated
water.(Thisapplianceissuitableforfillinglargeor
whirlpoolspatubswithpotablewater.)
• Donotusesubstutepartsthatarenotauthorized
forthisappliance.
MUSTDO
• Theinstallaonmustconformwithlocalcodesor,
intheabsenceoflocalcodes,withtheNaonal
Fuel Gas Code, ANSI Z223.1/NFPA 54,orthe
Natural Gas and Propane Installaon Code, CSA
B149.1.Ifinstalledinamanufacturedhome,the
installaonmustconformwiththeManufactured
Home Construcon and Safety Standard, Title 24
CFR, Part 3280and/orCAN/SCA Z240 MH Series,
Mobile Homes.
• Theappliance,wheninstalled,mustbeelectrically
groundedinaccordancewithlocalcodesor,inthe
absenceoflocalcodes,withtheNaonal Electrical
Code, ANSI/NFPA 70,ortheCanadian Electrical
Code, CSA C22.1.
• Theapplianceanditsappliancemaingasvalve
mustbedisconnectedfromthegassupplypiping
systemduringanypressuretesngofthatsystem
attestpressuresinexcessof1/2psi(3.5kPa)
(13.84inW.C.).
Typeofinstallaon
• Forinstallaoninresidenalandcommercial
applicaons.
• Cerfiedforinstallaoninmanufactured(mobile)
homes.

VCSeriesManual5
Prepareforinstallaon
Partsincluded
Toolsneeded
Materialsneeded
• Theappliancemustbeisolatedfromthegassupply
pipingsystembyclosingitsindividualmanual
shutoffvalveduringanypressuretesngofthegas
supplypipingsystemattestpressuresequaltoor
lessthan1/2psi(3.5kPa)(13.84inW.C.).
• Youmustfollowtheinstallaoninstruconsand
thoseinCare and Maintenanceforadequate
combusonairintakeandexhaust.
INFORMATION
• Ifawaterheaterisinstalledinaclosedwater
supplysystem,suchasonehavingabackflow
preventerinthecoldwatersupplyline,means
shallbeprovidedtocontrolthermalexpansion.
Contactthewatersupplierorlocalplumbing
inspectoronhowtocontrolthermalexpansion.
• Shouldoverheangoccurorthegassupplyfailto
shutoff,turnoffthemanualgascontrolvalveto
theappliance.
• Keeptheairintakelocaonfreeofchemicalssuch
aschlorineorbleachthatproducefumes.These
fumescandamagecomponentsandreducethelife
ofyourappliance.
• Tanklesswaterheater
• Colorcodedcold(blue)andhot(red)isolaon
valves
• Pressurereliefvalve
• MC‐91‐2temperaturecontroller(integratedinto
indoormodels;providedwithoutdoormodels)
• Pipewrenches(2)
• Adjustablepliers
• Screwdrivers(2)
• Wirecuers
• Gloves
• Safetyglasses
• Level
Toolsthatmightbeneeded
• Hammerdrillwith
concretebits
• Saw
• Threadingmachinewith
headsandoiler
• Coredrillwithdiamond
head
• Torchset
• Coppertubingcuer
• Steelpipecuer
Materialsthatmaybeneeded
• Soapsoluon
• Approvedvenng
• Teflontape
(recommended)orpipe
compound
• Heattape
• Pipeinsulaon
• Electricalwireand
conduitperlocalcode
• Concretewallanchors
• Oponalpipecover
• Oponaltemperature
controller
• 5/8”IDPVCflexible
tubing
• 2conductor22AWG
wireforcontroller
• Singlegangelectrical
box
• Wirenuts
• Unionsanddrainvalves

6VCSeriesManual
Consideraonofcareforyourwaterheatershould
includeevaluaonofwaterquality.
Waterthatcontainschemicalsexceedingthelevels
belowaffectanddamagetheheatexchanger.
Replacementoftheheatexchangerduetowater
qualitydamageisnotcoveredbythewarranty.
MaximumLevel
TotalHardnessUpto200mg/L
Aluminum*Upto0.2mg/L
Chlorides*Upto250mg/L
Copper*Upto1.0mg/L
Iron*Upto0.3mg/L
Manganese*Upto0.05mg/L
pH*6.5to8.5
TDS(TotalDissolved
Solids)*
Upto500mg/L
Zinc*Upto5mg/L
DetermineInstallaonLocaon
Environment
Airsurroundingthewaterheater,venng,andvent
terminaon(s)isusedforcombusonandmustbe
freeofanycompoundsthatcausecorrosionof
internalcomponents.Theseincludecorrosive
compoundsthatarefoundinaerosolsprays,
detergents,bleaches,cleaningsolvents,oilbased
paints/varnishes,andrefrigerants.Theairinbeauty
shops,drycleaningstores,photoprocessinglabs,and
storageareasforpoolsuppliesoencontainsthese
compounds.Thereforeitisrecommendedthat
outdoormodelsbeusedfortheselocaonswhere
possible.
Thewaterheater,venng,andventterminaon(s)
shouldnotbeinstalledinanyareaswheretheairmay
containthesecorrosivecompounds.Ifitisnecessary
forawaterheatertobelocatedinareaswhichmay
containcorrosivecompounds,thefollowing
instruconsarestronglyrecommended.
IMPORTANTCONSIDERATIONSFOR:
Indoor/InternalWaterHeaters
• DONOTInstallinareaswhereairforcombuson
canbecontaminatedwithchemicals.
• Beforeinstallaon,considerwhereairhasthe
abilitytotravelwithinthebuildingtothewater
heater.
• Wherepossible,installthewaterheaterina
sealedclosetsothatitisprotectedfromthe
potenalofcontaminatedindoorair.
• Chemicalsthatarecorrosiveinnatureshouldnot
bestoredorusednearthewaterheater.
Outdoor/ExternalWaterHeatersandVent
TerminaonsofIndoor/InternalWaterHeaters
• Installthewaterheaterasfarawayaspossible
fromexhaustventhoods.
• Installasfarawayaspossiblefromairinlet
vents.Corrosivefumesmaybereleasedthrough
theseventswhenairisnotbeingbroughtin
throughthem.
• Chemicalsthatarecorrosiveinnatureshouldnot
bestoredorusednearthewaterheaterorvent
terminaon.
Damageandrepairduetocorrosivecompoundsin
theairisnotcoveredbywarranty.
WaterQuality
*Source:Part143NaonalSecondaryDrinkingWater
Regulaons
Ifyouinstallthiswaterheaterinanareathatis
knowntohavehardwaterorthatcausesscalebuild‐
upthewatermustbetreatedand/ortheheat
exchangerflushedregularly.
Whenscalebuild‐upintheheatexchangerbeginsto
affecttheperformanceofthewaterheater,a
diagnosccode“LC#”willdisplay.Flushtheheat
exchangertopreventdamagetoit.Scalebuildupis
causedbyhardwatersetatahightemperature.
Rinnaiprovidesa“ScaleControlSystem”thatoffers
superiorlimescaleprevenonandcorrosioncontrol
byfeedingablendofcontrolcompoundsintothe
watersupply.
Youmustensurethatclearanceswillbemetandthat
theventlengthwillbewithinrequiredlimits.
Considertheinstallaonenvironment,waterquality,
andneedforfreezeprotecon.Requirementsforthe
gasline,waterlines,electricalconnecon,and
condensatedisposalcanbefoundintheirrespecve
installaonseconsofthismanual.

VCSeriesManual7
VentTerminaonClearances
INSIDE
CORNERDETAIL
FIXED
CLOSED
OPERABLE
FIXED
CLOSED
OPERABLE
B
B
B
A
J
BM
C
F
B
B
E
D
L
G
A
H
K
I
[1]Aventshallnotterminatedirectlyaboveasidewalkorpaveddriveway
thatislocatedbetweentwosinglefamilydwellingsandservesboth
dwellings.
[2]Permiedonlyifveranda,porch,deck,orbalconyisfullyopenona
minimumoftwosidesbeneaththefloor.
∗ ForclearancesnotspecifiedinANSI Z223.1/NFPA 54,clearancesarein
accordancewithlocalinstallaoncodesandtherequirementsofthegas
supplier.
Clearancetooppositewallis24inches(60cm).
X
V
AIRSUPPLYINLET
VENTTERMINAL
AREAWHERETERMINAL
ISNOTPERMITTTED
Forindoormodels,youmustinstallaventterminaontobringincombusonairandexpelexhaust.
SNOW
TERMINATION
Clearance in
Ref. A also
applies to
anticipated
snow line
RefDescriponCanadianInstallaonsUSInstallaons
AClearanceabovegrade,veranda,porch,deck,orbalcony12inches(30cm)12inches(30cm)
BClearancetowindowordoorthatmaybeopened36inches(91cm)12inches(30cm)
CClearancetopermanentlyclosedwindow**
D
Vercalclearancetovenlatedsoffit,locatedabovetheterminalwithin
ahorizontaldistanceof2feet(61cm)fromthecenterlineofthe
terminal
**
EClearancetounvenlatedsoffit**
FClearancetooutsidecorner**
GClearancetoinsidecorner**
HClearancetoeachsideofcenterlineextendedabovemeter/regulator
assembly
3feet(91cm)withinaheight15
feet(4.5m)abovethemeter/
regulatorassembly
*
IClearancetoserviceregulatorventoutlet36inches(91cm)*
JClearancetononmechanicalairsupplyinlettobuildingorthe
combusonairinlettoanyotherappliance36inches(91cm)12inches(30cm)
KClearancetoamechanicalairsupplyinlet6feet(1.83m)3feet(91cm)aboveifwithin10
feet(3m)horizontally
LClearanceabovepavedsidewalkorpaveddrivewaylocatedonpublic
property7feet(2.13m)1*
MClearanceunderveranda,porch,deck,orbalcony 12inches(30cm)2 *

8VCSeriesManual
24"
V
Checkonwhetherlocalcodessupersedetheseclearances.
• Avoidterminaonlocaonsnearadryervent.
• Avoidterminaonlocaonsnearcommercial
cookingexhaust.
• Youmustinstallaventterminaonatleast12
inchesfromtheground.
60"
V
V
(1.52m)
between
terminalsat
differentlevels
(0.61m)towallorparapet

(0.30m)between
terminalsatsame
level
12"
V V
(1.52m)vercally
betweenterminals
V
60"
V
Addionalclearances‐RL75i,RL94i
12"
12"
36"
INSIDE
CORNER
VV
(0.30m)to
aninside
corner(0.30m)between
terminalsatsame
level

Importantconsideraonsforlocangvent
terminaonunderasoffit(venlatedorunvenlated
oreavevent;ortoadeckorporch)
• Donotinstallventterminaonunderasoffitvent
suchthatexhaustcanenterthesoffitvent
• Installventterminaonsuchthatexhaustand
risingmoisturewillnotcollectunder
eaves.Discoloraontotheexteriorofthe
buildingcouldoccurifinstalledtooclose.
• Donotinstalltheventterminaontooclose
underthesoffitwhereitcouldpresent
recirculaonofexhaustgasesbackintothe
combusonairintakepartoftheterminaon.

VCSeriesManual9
2"
12"
60"
36"
Localcodessupersedetheseclearances.
• Avoidterminaonlocaonsnearadryervent.
• Avoidterminaonlocaonsnearcommercial
cookingexhaust.
Addionalclearances
RL75e,RL94e
(0.30m)toan
insidecorner
(50mm)betweenterminalsatsamelevel
(1.52m)vercally
betweenterminals
(0.91m)tovenlatedorunvenlated
soffitorevevent;ortoadeckorporch

10VCSeriesManual
Unitclearances
*0inchesfromventcomponentsandcondensate
drainline.
Theclearanceforservicingis24inchesinfrontofthe
waterheater.
Forclosetinstallaon,clearanceis6inches(152mm)
fromthefront.
Indoormodels:RL75i,RL94iOutdoormodels:RL75e,RL94e
Theclearanceforservicingis24inchesinfrontofthe
waterheater.
toCombusbles
inches(mm)
toNon‐
Combusbles
inches(mm)
TopofHeater12(305)2(51)
BackofHeater0(zero)0(zero)
Front(Panel)24(610)0(zero)
Front(Exhaust)24(610)24(610)
SidesofHeater6(152)1/8(3.2)
Ground/Boom12(305)2(51)
toCombusbles
inches(mm)
toNon‐
Combusbles
inches(mm)
TopofHeater6*(152)2*(51)
BackofHeater0(zero)0(zero)
FrontofHeater6(152)6(152)
SidesofHeater2(51)1/2(13)
Ground/Boom12(305)12(305)
Vent0(zero)0(zero)
to side
to front
to top
to ground/bottom
to side
to front
to top
to ground/bottom

VCSeriesManual11
FreezeProtecon
Makesurethatincaseoffreezingweatherthatthe
waterheateranditswaterlinesareprotectedto
preventfreezing.Damageduetofreezingisnot
coveredbythewarranty.
Lossoffreezeproteconmayresultinwaterdamage
fromaburstheatexchangerorwaterlines.
Withelectricalpowersupplied,thewaterheaterwill
notfreezewhentheoutsideairtemperatureisascold
as–22°F(‐30°C)forindoormodelsorisascoldas–4°F
(‐20°C)foroutdoormodels,whenprotectedfrom
directwindexposure.Becauseofthe“wind‐chill”
effect,anywindorcirculaonoftheairontheunit
willreduceitsabilitytofreezeprotect.
Theunitmaybedrainedmanually.However,itis
highlyrecommendedthat:
• draindownsolenoidvalvesareinstalledthatwill
automacallydraintheunitifpowerislost.
Theseareavailableinakit,104000059.(The
condensatetrapdrainplugandwaterdrainplug
arenotaffectedbytheautodraindownsolenoid
valvesandwillhavetobemanuallyopened.)
• asurgeprotectorwithterminalsisinstalledwhich
allowsthesolenoidvalvestooperateiftheunitis
disabledduetoadiagnosccode.Thisis
availableas104000057.
Inaddion,thesolenoidvalvesshouldbeconnected
electricallytoasurgeprotectorwithterminals.This
allowsthesolenoidvalvestooperateifthewater
heaterisdisabledduetoadiagnosccode.
Thefreezeproteconfeatureswillnotpreventthe
externalpipingfromfreezing.Itisrecommendedthat
hotandcoldwaterpipesareinsulated.Pipecover
enclosuresmaybepackedwithinsulaonforadded
freezeprotecon.
Intheeventofapowerfailureattemperaturesbelow
freezingthewaterheatershouldbedrainedofall
watertopreventfreezingdamage.Inaddion,drain
thecondensatetrapanddrainline.

Maximumventlength
(indoormodelsonly)
1.Determinethenumberof90degreeelbowsin
theventsystem.(Two45degreeelbowscountas
one90degreeelbow.)
2.Refertothetabletofindthemaximumvent
lengthbasedonthenumberofelbows.
3.AdjustswitchNo.1intheSW1DIPswitch(tan
switches)ifrequiredbytheapplicablenote.
1 Ifthelengthisgreaterthan21(6.4m)then
moveswitchNo.1(SW1)toOFF.
2 Ifthelengthisgreaterthan15(4.6m)then
moveswitchNo.1(SW1)toOFF.
3 Ifthelengthisgreaterthan9(2.7m)thenmove
switchNo.1(SW1)toOFF.
4MoveswitchNo.1(SW1)toOFF.
Example:Ifyouhaveoneelbowthenyourmaximum
ventlengthis35feet(10.7m).Ifyour
actuallengthisgreaterthan15(4.6m)
thenmoveswitchno.1(SW1)toOFF.
Numberof
90°Elbows
Maximumventlength
041(12.5m)1
135(10.7m)2
229(8.8m)3
323(7.0m)4
417(5.2m)4
511(3.4m)4
65(1.5m)4
Ifyouhavealongerventlength(seeabove),switch
No.1isrequiredtobeintheOFFposion.This
ensuresthewaterheaterwillrunproperly.Blocked
fluediagnosccodesandshutdownsmayresultif
switchNo.1isnotinthecorrectposion.
NOTICE

12VCSeriesManual
MounttoWall
wallinstallaon
brackets
1.Idenfytheinstallaonlocaonandconfirmthat
theinstallaonwillmeetallrequiredclearances.
2.Securelyaachthewaterheatertothewall
usinganyoftheholesinthewallinstallaon
bracketswhichareatthetopandboomofthe
waterheater.Ensurethattheaachment
strengthissufficienttosupporttheweight.
Refertotheweightofthewaterheaterinthe
Specificaonssecon.
Usealevelingtooltoensurethatthewater
heaterislevel.Properoperaonrequiresthat
thewaterheaterbelevel.
NOTE:Thewaterheatershouldbeinstalledinan
uprightposion.Donotinstallupsidedownoronits
side.
ChecklisttoDetermineInstallaon
Locaon
□Thewaterheaterisnotexposedtocorrosive
compoundsintheair.
□Thewaterheaterlocaoncomplieswiththe
clearances.
□Forindoormodels,theplannedvenngwillnot
exceedthemaximumlengthforthenumberof
elbowsused.
□Theplannedvenngterminaon/airintake
locaonmeetstheclearances.
□Thewatersupplydoesnotcontainchemicalsor
exceedtotalhardnessthatwilldamagetheheat
exchanger.
□Astandard3prong120VAC,60Hzproperly
groundedwalloutlet(forindoormodels)orother
120VAC,60Hzsourceisavailable.
□Theinstallaonmustconformwithlocalcodesor,
intheabsenceoflocalcodes,withtheNaonal
Fuel Gas Code, ANSI Z223.1/NFPA 54,orthe
Natural Gas and Propane Installaon Code, CSA
B149.1.Ifinstalledinamanufacturedhome,the
installaonmustconformwiththeManufactured
Home Construcon and Safety Standard, Title 24
CFR, Part 3280and/orCAN/SCA Z240 MH Series,
Mobile Homes.
□Leavetheenremanualtapedtothewater
heater(indoormodels),temperaturecontroller
(outdoormodels),orgivetheenremanual
directlytotheconsumer.
RemovetheFrontPanel
Slidetheplasctrimpiecesoneachsideofthewater
heatertoexposethescrews.
Removethe4screwsandpulloffthefrontpanel.


VCSeriesManual13
ManufacturerListedandTestedVentProducts
forRL75iandRL94iTelephoneFaxContact
UbbinkRoluxVentSystem 800‐621‐9419678‐829‐1666www.rinnai.us
Heat‐FabSaf‐TVentSCsystem800‐772‐0739413‐863‐4803custsvc@heat‐fab.com,
www.heaab.com
Metal‐FabCorr/GuardVent/AirIntakeSystem800‐835‐2830316‐943‐2717[email protected],
www.metal‐fabinc.com
Installaonofvenng(indoormodelsonly)
Installthecorrectvenngforyourmodelaccordingtothevenngmanufacturer’sinstruconsandthe
guidelinesbelow.
Refertothemanufacturer’stechnicalliteratureforspecificpartnumbersandinstrucons.
VenngGuidelines
DONOT
• DonotusePVC,CPVC,ABSorgalvanizedmaterial
toventthisappliance.
• Donotcombineventcomponentsfromdifferent
manufacturers.
• Ventdiametermustnotbereduced.
• Donotconnectthevenngsystemwithan
exisngventorchimney.
• Donotcommonventwiththeventpipeofany
otherwaterheaterorappliance.
MUSTDO
• Thiswaterheaterisadirectventwaterheaterand
thereforeiscerfiedandlistedwiththevent
system.Youmustuseventcomponentsthatare
cerfiedandlistedwiththewaterheatermodel.
• Theventsystemmustventdirectlytotheoutside
ofthebuildinganduseoutsideairforcombuson.
• Avoiddipsorsagsinhorizontalventrunsby
installingsupportspertheventmanufacturer’s
instrucons.
• Supporthorizontalventrunseveryfourfeetand
allvercalventrunseverysixfeetorin
accordancewithlocalcodes.
• Venngshouldbeasdirectaspossiblewitha
minimumnumberofpipefings.
• Ventconneconsmustbefirmlypressedtogether
sothatthegasketsformanairghtseal.
• Theventpiececonnectedtothewaterheater
mustbesecuredwithoneself‐tappingscrew.
INFORMATION
• Refertotheinstruconsoftheventsystem
manufacturerforcomponentassembly
instrucons.
• Iftheventsystemistobeenclosed,itissuggested
thatthedesignoftheenclosureshallpermit
inspeconoftheventsystem.Thedesignofsuch
enclosureshallbedeemedacceptablebythe
installerorthelocalinspector.
NOTICE
Ifitbecomesnecessarytoaccessanenclosedvent
systemforserviceorrepairs,Rinnaiisnotresponsible
foranycostsordifficulesinaccessingthevent
system.Thewarrantydoesnotcoverobtaining
accesstoaventsysteminanenclosedenvironment.

14VCSeriesManual
FlueInstallaon(indoormodelsonly)
VercalTerminaon
(condensatecollectormustbeusedinallinstallaons)
3in(75mm)
minimum
3in(75mm)
minimum
HorizontalTerminaonusingthe
CondensateCollector
3in(75mm)
minimum
Condensate
Trap
Toadjustthecondensatecollectorposionorto
replacethefemaleventtopwithamaleventtop:
1.Loosenthe4screwsattherearbracket
2.Slidethebracketawayfromthefemaleventtop.
3.Removethe4screwsaachingthefemaleventtop
tothewaterheater.
4.Liupthefemaleventtopandreposionasdesired
(orreplacewithamaleventtop).
5.Installthe4screwsattheventtopandghtenthe4
screwsatthebracket.
Securethefirstventcomponenttothewaterheater
withoneself‐tappingscrewattheholelocatedabove
thecondensatecollector.
Bracket
CondensateCollector
SecuringScrew
HorizontalTerminaonwithoutusingtheCondensateCollector
MaximumHeight*
5feet(1.52m)
Regionsofcoldclimatewillcreatemore
condensateintheventsystem.The
condensatecollectorshouldbeusedin
coldclimates.
Ifmorethanoneelbowisusedinthe
vercalseconthecondensatecollector
mustbeused.
*Thecondensatecollectormustbeusedin
horizontalterminaonsifavercalrisein
theventsystemexceeds5.
Ifthecondensatecollectorisnotused,thedrainpipe
mustbecappedtopreventexhaustgasesand
condensatefromenteringthebuilding.Thecapis
suppliedontheappliance.
WARNING
Installthevenngterminaonaccordingtothediagramsandinstruconsbelow.

VCSeriesManual15
Condensate
(indoormodelsonly)
Condensateformaoncanoccurinhighefficiency
directventappliances.Withoutproperdrainage
condensatewilldamagetheheatexchanger.
Topreventcondensatedamagefollowthese
instrucons.
DONOT
• Donotallowcondensatetoenterthewater
heater.
• Donotconnectthecondensatedrainpipedirectly
totherainsewer.
• Donotconnectthecondensatedrainlinewithan
aircondioningevaporatorcoildrain.
MUSTDO
• Useonlyventthatisapprovedandidenfiedas
acceptableforyourparcularmodel.
• Forvercalterminaons,installacondensatedrain
andtrapascloseaspossibletotheappliance.
• Slopethevenngtowardtheapplianceaccording
totheventmanufacturersinstallaoninstrucons.
• Allcondensatemustdrainandbedisposedof
accordingtolocalcodes.
• UseonlyPVCorCPVCpipeforthecondensate
drainline.
• Thecondensatedrainpipe(alongitsenrelength)
mustbeatleastthesamediameterasthedrain
line,(5/8inchNPT).
• Theendofthecondensatedrainpipeshouldbe
opentotheatmosphere.Theendshouldnotbe
underwaterorothersubstances.
• Tominimizefreezingofthecondensate,runthe
condensatedrainlinethroughaninteriorwallor
betweeninsulaonandaninteriorwall.
• Thecondensatecollectorshouldbeusedforall
hydronicheangapplicaons.
ChecklistforVenngand
Condensate(indoormodelsonly)
□Verifyproperclearancesaroundtheventsandair
intakes.
□Ensureyouhaveusedthecorrectvenng
productsforthemodelinstalledandthatyou
havecompletelyfollowedthevenng
manufacturer’sinstallaoninstruconsandthese
installaoninstrucons.
□Verifythattheventpipehasadownwardslopeor
gradetotheoutsideof1/4inchperfoot(1.2° )
ORiftheventpipeisslopedtowardthewater
heater(assomelocalcodesrequire),thata
condensatecollectorisinstalledtoallow
condensaontodrainawayfromthewater
heatertoaproperdrainsource.
□Verifythatcondensatewillnotbeallowedto
drainbackintothewaterheater.
□Verifythattheventsystemdoesnotexceedthe
maximumlengthforthenumberofelbowsused.
INFORMATION
• Acondensatetrapisavailable,P/N222053.
• Regionsofcoldclimatewillcreatemore
condensateintheventsystem.Thecondensate
collectorshouldbeusedincoldclimates.
• Thecondensatedrainpipeshouldbeasshortas
possibleandhaveadownwardpitch.

16VCSeriesManual
InstallaonofPlumbing
Amanualwatercontrolvalvemustbeplacedinthe
waterinletconnecontothewaterheaterbeforeitis
connectedtothewaterline.Unionsmaybeusedon
boththehotandcoldwaterlinesforfutureservicing
anddisconneconoftheunit.
DONOT
• Donotintroducetoxicchemicalssuchasthose
usedforboilerwatertreatmenttothepotable
waterusedforspaceheang.
MUSTDO
• Thepiping(includingsolderingmaterials)and
componentsconnectedtothisappliancemustbe
approvedforuseinpotablewatersystems.
• Purgethewaterlinetoremovealldebrisandair.
Debriswilldamagethewaterheater.
• Iftheappliancewillbeusedasapotablewater
source,itmustnotbeconnectedtoasystemthat
waspreviouslyusedwithanonpotablewater
heangappliance.
• Ensurethatthewaterfilteronthewaterheateris
cleanandinstalled.
PipingRequirements
PressureReliefValveRequirements
Installthepressurereliefvalveaccordingtothese
instrucons.
Anapprovedpressurereliefvalveisrequiredbythe
American Naonal Standard (ANSI Z21.10.3) forall
waterheangsystems,andshallbeaccessiblefor
servicing.
DONOT
• Donotplugthereliefvalveanddonotinstallany
reducingfingsorotherrestriconsintherelief
line.Therelieflineshouldallowforcomplete
drainageofthevalveandtheline.
• Donotplaceanyothertypevalveorshutoff
devicebetweenthereliefvalveandthewater
heater.
MUSTDO
• Thereliefvalvemustcomplywiththestandardfor
Relief Valves and Automac Gas ShutoffDevices for
Hot Water Supply Systems ANSI Z21.22and/orthe
standardTemperature, Pressure, Temperature and
Pressure Relief Valves and Vacuum Relief Valves,
CAN1‐4.4.
• Thereliefvalvemustberatedupto150psiandto
atleastthemaximumBTU/hroftheappliance.
• Thedischargefromthepressurereliefvalveshould
bepipedtothegroundorintoadrainsystemto
preventexposureorpossibleburnhazardsto
humansorotherplantoranimallife.Followlocal
codes.Waterdischargedfromthereliefvalve
couldcausesevereburnsinstantly,scalds,or
death.
• Thepressurereliefvalvemustbemanually
operatedonceayeartocheckforcorrect
operaon.
• Thereliefvalveshouldbeaddedtothehotwater
outletlineandnearthehotwateroutletaccording
tothemanufacturer’sinstrucons.DONOTplace
anyothertypevalveorshutoffdevicebetween
thereliefvalveandthewaterheater.
INFORMATION
• Ifareliefvalvedischargesperiodically,thismaybe
duetothermalexpansioninaclosedwatersupply
system.Contactthewatersupplierorlocal
plumbinginspectoronhowtocorrectthis
situaon.Donotplugthereliefvalve.
• TheAmerican Naonal Standard (ANSI Z21.10.3)
doesnotrequireacombinaontemperatureand
pressurereliefvalveforthisappliance.However,
localcodesmayrequireacombinaon
temperatureandpressurereliefvalve.
IsolaonValves
Isolaonvalvesareincludedwiththiswaterheater.
Rinnaistronglyrecommendstheinstallaonof
isolaonvalvesonthecoldandhotwaterlines
becausetheyprovidetheabilitytoisolatethewater
heaterfromthestructure’splumbingandallowquick
accesstoflushtheheatexchanger.Flushingtheheat
exchangerregularlyisrequiredaspartoftheproper
maintenanceforthiswaterheater.

VCSeriesManual17
IsolaonValvesandPressureReliefValve
Theisolaonvalvesprovidetheabilitytoisolatethe
waterheaterfromthestructure’splumbingandallow
quickaccesstoflushtheheatexchanger.Checkwith
localcodestodetermineifapressureand
temperaturereliefvalveisrequired.Theincluded
valvesmeetAmerican Naonal Standard (ANSI
Z21.10.3) / Canadian Standard (CSA 4.3)andare
ANSI/NSF61approvedforpotablewater.
IsolaonValvesInstallaonInstrucons:
1.Wraptheendsofthethreadedwaterinlet&
outletonthetanklesswaterheater,aswellas
thethreadedendoftheapprovedpressurerelief
valvewithaminimumof5wrapsofTeflon®
tape.
2.Screwthepressurereliefvalveintothe3/4”
threadsoppositethewinghandleontheHOT
waterservicevalve.(REDdrainhandle)(see
PressureReliefValveSeconforproper
installaonrequirements)
3.Loosenthe3/4”unionnutontheHOTwater
valveandconnecttotheHOTwateroutleton
thetanklesswaterheater.Ifnutisremoved,
ensurethatyourealignthetailpieceaccurately
tothevalveandthattheblackwasheris
posionedsuchthattheraisedmetaledgeof
thevalveisinsidethewasher.
4.AlignthedireconoftheHOTwaterdraintothe
desiredposion.
5.TightentheunionassemblytotheHOTwater
valveusingapproximately15footlbsoftorque.
6.Repeatsteps3‐5fortheCOLDwatervalve.
(BLUEdrainhandle)forconnecontotheCOLD
waterinletonthetanklesswaterheater.
7.ConnecttheINLETontheCOLDwatervalveto
theMAINSOURCEofthewatersupply.
8.ConnecttheOUTLETontheHOTwatervalveto
theHOTWATERplumbingsystem.
9.Ensurethatbothdrainvalveleverhandlesarein
theclosedposion(perpendiculartothedrain
poronofthebody).
PressureReliefValveInstallaonInstrucons:
ThePRVmustbeconnectedbythethreaded
conneconoppositethewinghandleonthehot
watervalve(designatedbytheREDdrainhandle)or
thethreadedconnecononthesideoftherelocaon
fingabovethehotwatervalve.Installaonmust
maintaina¾”portsizewithnoshutoffvalveorline
restriconin‐betweentheapplianceandthePRV.The
dischargelinefromthePRVshouldpitchdownward
andterminate6”abovedrainswheredischargewill
beclearlyvisible.Thedischargeendofthelineshall
beplain(unthreaded)andaminimumof¾”in
diameter.Thedischargelinematerialmustbe
suitableforwateratleast180°Fahrenheitandcanbe
nomorethan30feetinlengthandcontainnomore
than4elbowsorbends.Novalveofanytypemaybe
installedinthedischargelineofthepressurerelief
valve.
PressureReliefValveMaintenance:
Forpropercareofthisapprovedpressurereliefvalve,
itisrecommendedthatthevalveismanually
operatedonceayear.Indoingso,itwillbenecessary
totakeprecauonswithregardtothedischargeof
potenallyscaldinghotwaterunderpressure.Ensure
dischargehasaplacetoflow.Contactwithyourbody
orotherpropertymaycausedamageorharm.
PleasenotethatonlythePRVinthispackageis
cerfiedbyCSAInternaonalasanapproveditem.
APressureReliefValve(PRV)
BPRVDischargeOutlet
CHotBallValveDrainHandle
DColdBallValveDrainHandle
A
B
C
D

18VCSeriesManual
PipingDiagramforBasicInstallaon
GasSupply
3/4"ColdWaterSupplyLine
3/4" HotWater Supply Line
Rinnai
Water Heater
Rinnai
Equipment List
Rinnai
Water Heaters
RIK-KIT (Optional)
(3/4" Fittings Include:
2 Unions, 2 Ball Valves,
2DrainValvesand
1 Pressure Relief Valve.)
QTY
1
1
3/4"GasConnection
For Building Fixtures
Pressure Relief Valve
3/4" Ball Valve
3/4" Union
Check Valve
S
Pressure Regulator
Circulating Pump
Solenoid Valve
Boiler Drain Valve
KEY
This is not an engineered drawing. It is intended only as a guide and not
as a replacement for professionally engineered project drawings. This
drawing is not intended to describe a complete system. It is up to the
contractor/engineer to determine the necessary components and
configuration of the particular system being installed. This drawing does
not imply compliance with local building code requirements. It is the
responsibility of the contractor/engineer to ensure installation is in
accordance with all local building codes. Confer with local building
officials before installation.
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VCSeriesManual19
ConnectWaterHeatertoWaterSupply
Waterconneconstothetanklesswaterheater
shouldfollowallstateandlocalplumbingcodes.
Ifthisisastandardinstallaon,refertothePiping
DiagramforBasicInstallaon.
1.Plumbwatersupplytothetanklesswaterheater
onthe3/4”MNPTconneconattheboomof
theunitmarked“WaterInlet”,whichisthecold
watersupply.
2.Plumbthebuildinghotwatersupplytothe3/4”
MSPTconneconmarked“WaterOutlet”,which
isthehotwatersupply.
Ifapipecoverwillbeinstalled,makesurewaterlines
tothewaterheaterfit.
ChecklistforPlumbing
□Purgethewaterlineofalldebrisandairby
closingthehotisolaonvalveandopeningthe
coldisolaonvalveanditsdrain.Debriswill
damagethewaterheater.Useabucketorhose
ifnecessary.
□Ensurethathotandcoldwaterlinesarenot
crossedtotheunitandareleakfree.
□Ensurethatapressurereliefvalveisinstalledwith
arangthatexceedstheBTUinputofthewater
heatermodel.Refertotherangplateonthe
sideofthewaterheaterforBTUinput.
□Cleantheinletwaterfilterbyclosingthecoldand
hotwaterinletisolaon(shut‐off)valves.Puta
bucketunderthefilterattheboomofthewater
heatertocatchanywaterthatiscontainedinside
theunit.Unscrewthewaterfilter.Rinsethe
filtertoremoveanydebris.Installthefilterand
opentheisolaonvalves.
□Checkforproperwaterpressuretothewater
heater.Minimumwaterpressureis50psi.Rinnai
recommends60‐80psiformaximum
performance.
InstallaonofGasSupply
MUSTDO
• Amanualgascontrolvalvemustbeplacedinthe
gassupplylinetothewaterheater.Aunioncanbe
usedontheconneconabovetheshutoffvalve
forthefutureservicingordisconneconofthe
unit.
• Checkthetypeofgasandthegasinletpressure
beforeconnecngthewaterheater.Ifthewater
heaterisnotofthegastypethatthebuildingis
suppliedwith,DONOTconnectthewaterheater.
Contactthedealerfortheproperunittomatchthe
gastype.
• Checkthegassupplypressureimmediately
upstreamatalocaonprovidedbythegas
company.Suppliedgaspressuremustbewithin
thelimitsshownintheSpecificaonsseconwith
allgasappliancesoperang.
• Beforeplacingtheapplianceinoperaonalljoints
includingtheheatermustbecheckedforgas
ghtnessbymeansofleakdetectorsoluon,soap
andwater,oranequivalentnonflammable
soluon,asapplicable.(Sincesomeleaktest
soluons,includingsoapandwater,maycause
corrosionorstresscracking,thepipingshallbe
rinsedwithwateraertesng,unlessithasbeen
determinedthattheleaktestsoluonisnon‐
corrosive.)
• Useapprovedconnectorstoconnecttheunitto
thegasline.Purgethegaslineofanydebris
beforeconnecontothewaterheater.
GeneralInstrucons
WARNING
1.Ifyouarenotknowledgeableorqualifiedto
installgaslinesorconnecons,thencontacta
licensedprofessionaltoinstallthegassupply.
2.Turnoff120vpowersupply.
3.Turnoffthegas.
4.Gasisflammable.Donotsmokeorprovideother
ignionsourceswhileworkingwithgas.
5.Donotturnonthewaterheaterorgasunlall
fumesaregone.

20VCSeriesManual
Sizethegaspipe
Thegassupplymustbecapableofhandlingtheenre
gasloadatthelocaon.Gaslinesizingisbasedon
gastype,thepressuredropinthesystem,thegas
pressuresupplied,andgaslinetype.Forgaspipesiz‐
ingintheUnitedStates,refertotheNaonal Fuel Gas
Code, NFPA 54.Thebelowinformaonisprovidedas
anexample.Theappropriatetablefromtheapplica‐
blecodemustbeused.
1.Forsometables,youwillneedtodeterminethe
cubicfeetperhourofgasrequiredbydividingthe
gasinputbytheheangvalueofthegas
(availablefromthelocalgascompany).Thegas
inputneedstoincludeallgasproductsatthelo‐
caonandthemaximumBTUusageatfullload
whenallgasproductsareinuse.
2.Usethetableforyourgastypeandpipetypeto
findthepipesizerequired.Thepipesizemustbe
abletoprovidetherequiredcubicfeetperhour
ofgasortherequiredBTU/hour.
Example:
Theheangvalueofnaturalgasforyourlocaonis
1000BTU/FT3.ThegasinputoftheRL94iis199,000
BTU/HR.Addionalappliancesatthelocaonrequire
65,000BTU/hr.Thereforethecubicfeetperhour=
(199,000+65,000)/1000=264FT3/HR.Ifthepipe
lengthis10feetthenthe3/4inchpipesizeiscapable
ofsupplying264FT3/HRofnaturalgas.
GasInputofallgasproducts(BTU/HR)
HeangValueofGas(BTU/FT3)
CubicFeet
perHour=
(CFH)
• Anycompoundusedonthethreadedjointofthe
gaspipingshallbeatypewhichresiststheacon
ofliquefiedpetroleumgas(propane/LPG).
• Thegassupplylineshallbegasght,sized,andso
installedastoprovideasupplyofgassufficientto
meetthemaximumdemandoftheheaterandall
othergasconsumingappliancesatthelocaon
withoutlossofpressure.
INFORMATION
• Refertoanapprovedpipesizingchartifindoubt
aboutthesizeofthegasline.
Length
PipeSize(inches)
3/4111/411/2
1027351410601580
201883537261090
30151284583873
40129243499747
50114215442662
60104195400600
7095179368552
8089167343514
9083157322482
10079148304455
PipeSizingTable‐NaturalGas
InletPressure:lessthan2psi(55inchesW.C.)
PressureDrop:0.3inchesW.C.
SpecificGravity:0.60
Schedule40MetallicPipe
cubicfeetperhour
Length
PipeSize(inches)
1/23/4111/4
1029160811502350
202004187871620
301603366321300
401372875411110
50122255480985
60110231434892
80101212400821
10094197372763
PipeSizingTable‐PropaneGas
InletPressure:11.0inchesW.C.
PressureDrop:0.5inchesW.C.
SpecificGravity:1.50
Schedule40MetallicPipe
CapacityinThousandsofBTUperHour