AO Smith BL-80 100 Conservationist 74-Gallon Ultra-Low NOx User Manual

Instruction Manual

PRINTED 1215 324258-002

KEEP THIS MANUAL IN THE POCKET ON HEATER FOR FUTURE REFERENCE

WHENEVER MAINTENANCE ADJUSTMENT OR SERVICE IS REQUIRED.

ULTRA LOW NOX COMMERCIAL GAS WATER HEATERS

• For Your Safety •

AN ODORANT IS ADDED TO THE GAS USED

BY THIS WATER HEATER.

MODELS BL-80/BL-100

Series 100

INSTALLATION - OPERATION - SERVICE

- MAINTENANCE - LIMITED WARRANTY

PLACE THESE INSTRUCTIONS ADJACENT TO HEATER AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.

SAFE INSTALLATION, USE AND SERVICE...................... 3

APPROVALS ...................................................................... 3

GENERAL SAFETY INFORMATION .................................. 4

INTRODUCTION ................................................................ 5

Abbreviations Used ..................................................... 5

 QualiedInstallerorServiceAgency........................... 5

 PreparingfortheNewInstallation ............................... 5

INSTALLATION CONSIDERATIONS ................................. 6

 RoughInDimensions .................................................. 6

 Thermometers ............................................................. 7

 FactstoConsiderAboutTheLocation ........................ 7

 HighAltitude ................................................................ 8

 Clearances .................................................................. 8

Insulation Blankets ...................................................... 9

Hard Water .................................................................. 9

 CirculationPumps ....................................................... 9

INSTALLATION REQUIREMENTS .................................. 10

 GasSupplySystems ................................................. 10

 GasPressureRequirements ..................................... 10

 SupplyGasRegulator ............................................... 10

 MixingValves ............................................................ 10

 WaterPiping .............................................................. 11

 ClosedWaterSystems .............................................. 11

 ThermalExpansion ................................................... 11

 Temperature-PressureReliefValve ......................... 11

 FillingtheWaterHeater ............................................. 12

 AirRequirements....................................................... 12

 UnconnedSpace ..................................................... 13

 ConnedSpace ......................................................... 13

 FreshAirOpeningsforConnedSpaces .................. 13

 OutdoorAirThroughTwoOpenings .......................... 13

 OutdoorAirThroughOneOpening ........................... 13

 OutdoorAirThroughTwoHorizontalDucts ............... 14

 OutdoorAirThroughTwoVerticalDucts ................... 14

 AirFromOtherIndoorSpaces .................................. 14

 Venting ...................................................................... 14

 GasPiping ................................................................. 16

 SedimentTraps ......................................................... 17

LIGHTING & OPERATING INSTRUCTIONS ................... 18

TEMPERATURE REGULATION ...................................... 19

FOR YOUR INFORMATION ............................................. 19

Start Up Conditions ................................................... 19

Operational Conditions .............................................. 20

PERIODIC MAINTENANCE ............................................. 21

 VentingSystemInspection ........................................ 21

 BurnerInspection ...................................................... 21

 BurnerCleaning ........................................................ 21

 Housekeeping ........................................................... 21

 AnodeRodInspection ............................................... 22

 Temperature-PressureReliefValveTest ................... 22

RECOMMENDED PROCEDURE FOR PERIODIC

REMOVAL OF LIME DEPOSITS FROM TANK

TYPE COMMERCIAL WATER HEATERS ........................ 22

 DelimingSolvents...................................................... 23

 TankCleanoutProcedure .......................................... 23

 DelimingUsingFlo-JugMethod ................................ 23

 DrainingandFlushing ............................................... 24

 Service ...................................................................... 24

LEAKAGE CHECKPOINTS .............................................. 25

TROUBLESHOOTING GUIDELINES ............................... 26

WATER PIPING DIAGRAMS ............................................ 27

NOTES ............................................................................. 33

WARRANTY ..................................................................... 35

TABLE OF CONTENTS

SAFE INSTALLATION, USE AND SERVICE

Theproperinstallation,useandservicingofthiswaterheaterisextremelyimportanttoyoursafetyandthesafetyofothers.

Manysafety-relatedmessagesandinstructionshavebeenprovidedinthismanualandonyourownwaterheatertowarnyouand

othersofapotentialinjuryhazard.Readandobeyallsafetymessagesandinstructionsthroughoutthismanual.Itisveryimportant

thatthemeaningofeachsafetymessageisunderstoodbyyouandotherswhoinstall,use,orservicethiswaterheater.

Allsafetymessageswillgenerallytellyouaboutthetypeofhazard,whatcanhappenifyoudonotfollowthesafetymessage,and

howtoavoidtheriskofinjury.

DANGER

WARNING

CAUTION

DANGER indicates an imminently

hazardous situation which, if not avoided,

will result in injury or death.

This is the safety alert symbol. It is used to alert you to

potential personal injury hazards. Obey all safety

messages that follow this symbol to avoid possible

injury or death.

WARNING indicates a potentially hazardous

situation which, if not avoided, could result

in injury or death.

CAUTION indicates a potentially hazardous

situation which, if not avoided, could result in

minor or moderate injury.

CAUTION used without the safety alert

symbol indicates a potentially hazardous

situation which, if not avoided, could result in

property damage.

APPROVALS

Low Lead Content

GENERAL SAFETY INFORMATION

ThankYouforpurchasingthiswaterheater.Properlyinstalledand

maintained,itshouldgiveyouyearsoftroublefreeservice.

ABBREVIATIONS USED

AbbreviationsFoundInThisInstructionManual:

• UL-UnderwritersLaboratoriesInc.

• ANSI-AmericanNationalStandardsInstitute

• NFPA-NationalFireProtectionAssociation

• ASME-AmericanSocietyofMechanicalEngineers

• AHRI-Air-Conditioning,HeatingandRefrigerationInstitute

• CAN - Canada

• EPACT-EnergyPolicyAct

• CSA-CanadianStandardsAssociation

This gas-fired water heater is design certified by Underwriters

LaboratoriesInc.underAmericanNationalStandard/CSAStandard

forGasWaterHeatersANSIZ21.10.3•CSA4.3(currentedition).

QUALIFIED INSTALLER OR SERVICE AGENCY

Installationandserviceofthiswaterheaterrequiresabilityequivalent

tothatofaQualiedAgency(asdenedbyANSIbelow)intheeld

involved. Installation skills such as plumbing, air supply, venting,

gassupplyandelectricalsupplyarerequiredinadditiontoelectrical

testingskillswhenperformingservice.

ANSIZ223.12006Sec.3.3.83:“QualiedAgency”-“Anyindividual,

rm, corporation or company that either in person or through a

representativeisengagedinandisresponsiblefor(a)theinstallation,

testingorreplacementofgaspipingor(b)theconnection,installation,

testing, repair or servicing of appliances and equipment; that is

experiencedinsuchwork;thatisfamiliarwithallprecautionsrequired;

and that has complied with all the requirements of the authority

havingjurisdiction.”

Ifyouarenotqualied(asdenedbyANSIabove)andlicensedor

certiedasrequiredbytheauthorityhavingjurisdictiontoperforma

giventaskdonotattempttoperformanyoftheproceduresdescribed

in this manual. If you do not understand the instructions given in

this manual do not attempttoperformany procedures outlined in

thismanual.

PREPARING FOR THE INSTALLATION

1. ReadtheGeneralSafetyInformationsection,page4ofthis

manual first and then the entire manual carefully.  If you

don’tfollowthesafetyrules,thewaterheaterwillnotoperate

pr o p er l y.I t c oul d c auseD E AT H,S E R I OU S B O DI LYIN J U RY

AND/ORPROPERTYDAMAGE.

 This manual contains instructions for the installation,

oper a t ion,andm a int e nanc eo fthe gas - f ir e dwa terh e ate r. It

alsocontainswarningsthroughoutthemanualthatyoumust

readandbeawareof.Allwarningsandallinstructionsare

essentialtotheproperoperationofthewaterheaterandyour

safety.Sincewecannotputeverythingonthefirstfewpages,

READ THE ENTIRE MANUAL BEFORE ATTEMPTING TO

INSTALL OR OPERATE THE WATER HEATER.

2.The installation must conform with these instructions and

thelocalcodeauthorityhavingjurisdiction.Intheabsence

oflocalcodes,theinstallationmustcomplywiththecurrent

editions of the National Fuel Gas Code, ANSI Z223.1/

NFPA54orCAN /CSA - B149.1theNaturalGasandPropane

Installation Code. All documents are available from the

CanadianStandardsAssociation,8501EastPleasantValley

Road, Cleveland, OH 44131. NFPA documents are also

available from the National Fire Protection Association, 1

BatterymarchPark,Quincy,MA02269.

3.If after reading this manual you have any questions or do

notunderstandanyportionoftheinstructions,callthelocal

gasutilityorthemanufacturerwhosenameappearsonthe

ratingplate.

4.Carefully plan the place where you are going to put the

water heater.  Correct  combustion, vent action, and vent

pipeinstallationareveryimportantinpreventingdeathfrom

possiblecarbonmonoxidepoisoningandfires,seeFigures

3 and 7.

 Examinethelocationtoensurethewaterheaterc omplieswith

theFacttoConsiderAboutTheLocationsectioninthismanual.

5.For

ROUGH IN DIMENSIONS

INSTALLATION CONSIDERATIONS

FIGURE 1.

HOT WATER

OUTLET

DRAIN

VA LV E

HOT

COLD

TOP VIEW

GAS INLET

INSTALL IN ACCORDANCE WITH LOCAL CODES

DRAIN VALVE

COLD WATER

INLET

OUTER DOOR

(BURNER ASSEMBL Y BEHIND)

DRAFT HOOD

THERMOMETERS (Not Supplied)

Thermometersshouldbeobtainedandeldinstalled.

Thermometersareinstalledinthesystemasameansofdetecting

thetemperatureoftheoutletwatersupply.

ThisWaterHeaterhasbeendesigncertifiedascomplyingwith

ANSIZ21.10.3-CSA4.3currenteditionforwaterheatersandis

consideredsuitablefor:

Water (Potable) Heating and Space Heating: All models are

consideredsuitableforwater(potable)heatingandspaceheating.

HOTTERWATERCANSCALD:

Waterheatersareintendedtoproducehotwater.Waterheatedtoa

temperaturewhichwillsatisfyspaceheating,clotheswashing,dish

washing,andothersanitizingneedscanscaldandpermanentlyinjure

youuponcontact.Somepeoplearemorelikelytobepermanently

injuredbyhotwaterthanothers.Theseincludetheelderly,children,

theinrm,orphysically/mentallyhandicapped.Ifanyone

usedinthesameroomorareacontainingagaswaterheaterorother

openameorsparkproducingappliance.NOTE:Flammablevaporsmay

bedrawnbyaircurrentsfromotherareasofthestructuretotheappliance.

Also, the water heater must be located and/or protected so it is not

subjecttophysicaldamagebyamovingvehicle.

Thiswaterheatermustnotbeinstalleddirectlyoncarpeting.Carpeting

mustbeprotectedbymetalorwoodpanelbeneaththewaterheater

extendingbeyondthefullwidthanddepthofthewaterheaterbyatleast

3”(76.2mm)inanydirection,orifthewaterheaterisinstalledinan

alcoveorcloset,theentireoormustbecoveredbythepanel.Failure

toheedthiswarningmayresultinarehazard.

HIGH ALTITUDE

Waterheaterscoveredinthismanualhavebeentestedandapproved

for installation at elevations up to 7,700 feet (2,347 m) above sea

level.Forinstallationabove7,700feet(2,347m),thewaterheater’s

Btuinputshouldbereducedattherateof4percentforeach1,000

feet(305m)abovesealevelwhichrequiresreplacementoftheburner

oriceinaccordancewiththeNationalFuelGasCodeANSIZ223.1/

NFPA 54 or the Natural Gas and Propane Installation Code CAN/

CSAB149.1.Contactyourlocalgassupplierforfurtherinformation.

Failuretoreplacethestandardoricewiththeproperhighaltitude

orice when installed

INSULATION BLANKETS

Do not obstruct water heater air intake

with insulating blanket.

Gas and carbon monoxide detectors

are available.

Install water heater in accordance with

the instruction manual.

Breathing carbon monoxide can cause brain damage or

death. Always read and understand instruction manual.

Breathing Hazard - Carbon Monoxide Gas

GAS SUPPLY SYSTEMS

Low pressure building gas supply systems are dened as those

systemsthatcannotunderanycircumstancesexceed14”W.C.

(1/2PSIGauge).Thesesystemsdonotrequirepressureregulation.

Measurementsshouldbetakentoinsurethatgaspressuresarestable

andfallwithintherequirementsstatedonthewaterheaterratingplate.

readings should be taken with all gas burning equipment off (static

pressure)andwithallgasburningequipmentrunningatmaximumrate

(dynamicpressure).Thegassupplypressuremustbestablewithin1.5”

W.C. from static todynamicpressuretoprovide good performance.

Pressuredropsthatexceed1.5”W.C.maycauseroughstarting,noisy

combustionornuisanceoutages.Increasesorspikesinstaticpressure

duringoffcyclesmaycausefailuretoigniteorinseverecasesdamage

toappliancegasvalves.Ifyourlowpressuresystemdoesnotmeet

theserequirements,theinstallerisresponsibleforthecorrections.

HighPressurebuildingsupplysystemsusepressuresthatexceed

14” W.C. (1/2 PSI Gauge). These systems must use eld supplied

regulatorsto lower the gaspressure to less than 14” W.C. (1/2 PSI

Gauge).Appliancesrequiregasregulatorsthatareproperlysizedforthe

waterheaterinputanddelivertheratingplatespeciedpressures.Gas

supplysystemswherepressureexceeds5PSIoftenrequiremultiple

regulatorstoachievedesiredpressures.Systemsinexcessof5PSI

building pressure should be designed by gas delivery professionals

forbestperformance.Waterheatersconnectedtogassupplysystems

thatexceed14”W.C.(1/2PSIGauge)atanytimemustbeequipped

withagassupplyregulator.

GAS PRESSURE REQUIREMENTS

BL-100naturalgasmodelrequiresaminimumgassupplypressureof

5”w.c.(1.25kPa);BL-80naturalgasmodelrequiresaminimumgas

supplypressureof6”w.c.(1.49kPa).Theminimumsupplypressure

is measured while gas is owing (dynamic pressure). The supply

pressure(dynamic)shouldneverfallbelowthespeciedminimum

supplypressure.Thesupplypressureshouldbemeasuredwithallgas

redappliancesconnectedtothecommonmainringatfullcapacity.If

thesupplypressuredropsmorethan1.5”W.C.(0.37kPa)asgasbegins

toowtothewaterheaterthenthesupplygassystemincludingthe

gaslineand/orthegasregulatormayberestrictedorundersized.See

SupplyGasregulatorsectionandGasPipingsectionofthismanual.

Thegasvalveonallmodelshasamaximumgassupplypressurelimit

of14” W.C. 

valve

WATER PIPING

WATER (POTABLE) HEATING AND SPACE HEATING

Thiswaterheatershallnotbeconnectedtoanyheatingsystems

orcomponent(s)usedwithanon-potablewaterheatingappliance.

Allpipingcomponentsconnectedtothis unit for space heating

applicationsshallbesuitableforusewithpotablewater.

Toxicchemicals,suchasthoseusedforboilertreatmentshallnot

beintroducedintothissystem.

Whenthesystemrequireswaterforspaceheatingattemperatures

higherthanrequiredfordomesticwaterpurposes,amixingvalve

mustbeinstalled.PleaserefertoFigure6forsuggestedpiping

arrangement.

Thesewaterheaterscannotbeusedinspaceheatingapplications

only.

CLOSED WATER SYSTEMS

Water supply systems may, because of code requirements or

such conditions as high line pressure, among others, have

installed devices such as pressure reducing valves, check

valves,andbackflowpreventers.Devicessuchasthesecause

thewatersystemtobeaclosedsystem.

THERMAL EXPANSION

Aswaterisheated,itexpands(thermalexpansion).Inaclosed

systemthevolumeof waterwillgrowwhenit isheated.Asthe

volumeofwatergrowstherewillbeacorrespondingincreasein

water pressure due to thermal expansion. Thermal expansion

cancauseprematuretankfailure(leakage).Thistypeoffailure

is not covered under the limited warranty. Thermal expansion

canalso cause intermittent Temperature-Pressure ReliefValve

operation: water discharged from the valve due to excessive

pressurebuildup.Thisconditionisnotcoveredunderthelimited

warranty.TheTemperature-PressureReliefValveisnotintended

fortheconstantreliefofthermalexpansion.

A properly sized thermal expansion tank must be installed on

all closed systems to control the harmful effects of thermal

expansion.Contactalocalplumbingservicetechniciantohave

athermalexpansiontankinstalled.

FIGURE 7.

NOTE: To protect against untimely corrosion of hot and cold

waterttings, itisstronglyrecommended thatdi-electricunions

orcouplingsbeinstalledonthiswaterheaterwhenconnectedto

copperpipe.

Figure7showsthetypicalattachmentofthewaterpipingtothe

water heater.

NOTE: In addition to the factory installed Temperature-Pressure

Relief Valve on the water heater, each remote storage tank that

maybeinstalledandpipedtoawaterheatingappliancemustalso

have its own properly sized, rated and approved Temperature-

PressureReliefValveinstalled.Callthetollfreetechnicalsupport

phonenumberlistedonthebackcoverofthismanualfortechnical

assistanceinsizingaTemperature-PressureReliefValveforremote

storagetanks.

For safe operation of the water heater, the Temperature-Pressure

ReliefValvemustnotberemovedfromitsdesignatedopeningnor

plugged.TheTemperature-PressureReliefValvemustbeinstalled

directlyintothettingofthewaterheaterdesignedforthereliefvalve.

Installdischargepipingsothatanydischargewillexitthepipewithin

6inches(15.2cm)aboveanadequateoordrain,orexternaltothe

building.Incoldclimatesitisrecommendedthatitbeterminatedat

anadequatedraininsidethebuilding.Becertainthatnocontactis

madewithanyliveelectricalpart.Thedischargeopeningmustnot

beblockedorreducedinsizeunderanycircumstances.Excessive

length,over30feet(9.14m),oruseofmorethanfourelbowscan

causerestrictionandreducethedischargecapacityofthevalve.

No valve or other obstruction is to be placed between the

Temperature-PressureReliefValve andthetank. Donotconnect

dischargepipingdirectlytothedrainunlessa6”(15.2cm)airgapis

provided.Topreventbodilyinjury,hazardtolife,orpropertydamage,

the relief valve must be allowed to discharge water in adequate

quantitiesshouldcircumstancesdemand.Ifthedischargepipeis

notconnectedto a drain or other suitable means, thewaterow

maycausepropertydamage.

Water Damage Hazard

•

Temperature-Pressure Relief Valve discharge

pipe must terminate at adequate drain.

CAUTION

T&P Valve Discharge Pipe Requirements:

• Shallnotbesmallerinsizethantheoutletpipesizeofthevalve,

orhaveanyreducingcouplingsorotherrestrictions.

• Shallnotbepluggedorblocked.

• Shallnotbeexposedtofreezingtemperatures.

• Shallbeofmateriallistedforhotwaterdistribution.

• Shallbeinstalledsoastoallowcompletedrainageofboththe

Temperature-PressureReliefValveandthedischargepipe.

• Mustterminateamaximumofsixinchesaboveaoordrain

orexternaltobuilding.Incoldclimates,itisrecommended

thatdischargepipebeterminatedatanadequatedraininside

building.

• Shallnothaveanyvalveorotherobstructionbetweenthe

reliefvalveandthedrain.

amountofcombustionaircanresultinareorexplosionandcauseproperty

damage,seriousbodilyinjuryordeath.

UNCONFINED SPACE

An Unconfined Space is one whose volumeis not lessthan 50

cubic feet per 1,000 Btu/hr (4.8 cubic meters per kW) of the

totalinputratingofallappliancesinstalledinthespace.Rooms

communicating directly with the space, in which the appliances

are installed, through openings not furnished with doors, are

consideredapartoftheunconfinedspace.

Makeupairrequirementsfortheoperationofexhaustfans,kitchen

ventilation systems, clothes dryers and fireplaces shall also be

considered in determining the adequacy of a space to provide

combustion,ventilationanddilutionair.

UNUSUALLY TIGHT CONSTRUCTION

Inunconfinedspacesinbuildings,infiltrationmaybeadequateto

provideairforcombustion,ventilationanddilutionoffluegases.

However,inbuildingsofunusuallytightconstruction(forexample,

weatherstripping,heavilyinsulated,caulked,vaporbarrier,etc.)

additionalair must be provided using the methods described in

theConfinedSpacesectionthatfollows.

CONFINED SPACE

AConnedSpaceisonewhosevolumeislessthan50cubicfeetper

1,000Btu/hr(4.8cubicmetersperkW)ofthetotalinputratingofall

appliancesinstalledinthespace.

Openingsmustbeinstalledtoprovidefreshairforcombustion,ventilation

and dilution in conned spaces. The required size for the openings is

dependentonthemethodusedtoprovidefreshairtotheconnedspace

andthetotalBtu/hrinputratingofallappliancesinstalledinthespace.

DIRECT VENT APPLIANCES

Appliances installed in a Direct Vent conguration that derive all

air for combustion from the outdoor atmosphere through sealed

intakeair piping are not factored inthe total appliance input Btu/hr

calculationsusedtodeterminethesizeofopeningsprovidingfresh

airintoconnedspaces.

EXHAUST FANS

Whereexhaustfansareinstalled,additionalairshallbeprovided

toreplacetheexhaustedair.Whenanexhaustfanisinstalledin

thesamespacewithawaterheater,sufficientopeningstoprovide

freshairmustbeprovidedthataccommodatetherequirements

for all appliancesintheroomandthe exhaustfan. Undersized

openingswillcauseairtobedrawnintotheroomthroughthewater

heater’sventsystemcausingpoorcombustion.Sooting,serious

damagetothewaterheaterandtheriskoffireorexplosionmay

result.Itcanalsocreateariskofasphyxiation.

LOUVERS AND GRILLES

Thefreeareasofthefreshairopeningsintheinstructionsthatfollowdonot

takeintoaccountthepresenceoflouvers,grillesorscreensintheopenings.

Therequiredsizeofopeningsforcombustion,ventilationanddilution

airshallbebasedonthe“netfreearea”ofeachopening.Wherethe

freeareathroughadesignoflouverorgrilleorscreenisknown,itshall

beusedincalculatingthesizeofopeningrequiredtoprovidethefree

areaspecied.Wherethelouverandgrilledesignandfreeareaarenot

known,itshallbeassumedthatwoodlouverswillhave25%freearea

andmetallouversandgrilleswillhave75%freearea.Nonmotorized

louversandgrillesshallbexedintheopenposition.

FRESH AIR OPENINGS FOR CONFINED SPACES

The following instructions shall be used to calculate the size,

number and placement of openings providing fresh air for

combustion, ventilation and dilution in confined spaces. The

illustrationsshowninthissectionofthemanualareareference

for the openings that provide fresh air into confined spaces

only.Do not refer to these illustrations for the purpose of vent

installation. See Venting Installation on page 14 for complete

ventinginstallationinstructions.

OUTDOOR AIR THROUGH TWO OPENINGS

OUTDOOR AIR THROUGH TWO HORIZONTAL DUCTS

FIGURE 10.

Theconnedspaceshallbeprovidedwithtwopermanenthorizontal

ducts, one commencing within 12 inches (300 mm) of the top and

one commencing within 12 inches (300 mm) of the bottom of the

enclosure.Thehorizontalductsshallcommunicatedirectlywiththe

outdoors.SeeFigure10.

Eachductopeningshallhaveaminimumfreeareaof1squareinch

per2,000Btu/hr(1100mm2perkW)oftheaggregateinputratingof

allappliancesinstalledintheenclosure.

Whenductsareused,theyshallbeofthesamecrosssectionalarea

asthefreeareaoftheopeningstowhichtheyconnect.Theminimum

dimensionofrectangularairductsshallbenotlessthan3inches.

OUTDOOR AIR THROUGH TWO VERTICAL DUCTS

The illustrations shown in this section of the manual are a

reference for the openings that provide fresh air into conned

spacesonly.

DO NOT refer to these illustrations for the purpose of vent

installation. See Venting Installation on page 14 for complete

ventinginstallationinstructions.

FIGURE 11.

The conned space shall be provided with two permanent vertical

ducts, one commencing within 12 inches (300 mm) of the top and

one commencing within 12 inches (300 mm) of the bottom of the

enclosure. The vertical ducts shall communicate directly with the

outdoors.SeeFigure11.

Eachductopeningshallhaveaminimumfreeareaof1squareinch

per4,000Btu/hr(550mm2perkW)oftheaggregateinputratingof

allappliancesinstalledintheenclosure.

Whenductsareused,theyshallbeofthesamecrosssectionalarea

asthefreeareaoftheopeningstowhichtheyconnect.Theminimum

dimensionofrectangularairductsshallbenotlessthan3inches.

AIR FROM OTHER INDOOR SPACES

FIGURE 12.

Theconnedspaceshallbeprovidedwithtwopermanentopenings,

one commencing within 12 inches (300 mm) of the top and one

commencingwithin12inches(300mm)ofthebottomoftheenclosure.

SeeFigure12.

Eachopeningshallcommunicatedirectlywithanadditionalroom(s)

ofsufcientvolumesothatthecombinedvolumeofallspacesmeets

thecriteriaforanUnconnedSpace.

Eachopeningshallhaveaminimumfreeareaof1squareinchper

1,000Btu/hr(2200mm2perkW)oftheaggregateinputratingofall

appliancesinstalledintheenclosure.Eachopeningshallnotbeless

than100squareinches(645cm2).

VENTING

If the water heater is being installed as a replacement for an

existingheaterinpre-existingventing,athoroughinspectionof

existingventingsystemmustbeperformedpriortoanyinstallation

work.

VENT DAMPERS - Any vent damper, whether it is operated

thermallyorother wisemustberemovedifitsuseinhibitsproper

draftingofthewaterheater.

Thermally OperatedVent Dampers:thisgas-firedwater heater

has a thermal efficiency at or above 80% which may produce

a relatively low flue gas temperature. Such temperatures may

not be high enough to properly open thermally operated vent

dampers.Thiswouldcausespillageofthefluegasesandmay

cause carbon monoxide poisoning. Vent dampers must bear

evidenceofcertificationascomplyingwiththecurrenteditionof

th eA m er i c a n N a t io n a l S t an d a r d A N S I Z 21. 6 6C G A 6 .14(c o ve r i ng

electrically and mechanically actuated vent dampers). Before

installation of any vent damper,consultthe local gas utilityfor

furtherinformation.

Toinsurep r o p erve ntin goft h i s g a s - f i r e dwat e rheater, t h ec o r r e c t

ventpipediametermustbeutilized.Anyadditionsordeletions

ofothergasappliancesonacommonventwiththiswaterheater

mayadverselyaffecttheoperationofthewaterheater.Consult

yourgassupplierifanysuchchangesareplanned.

Forproperventingincertaininstallations,alargerdiametervent

pipemaybenecessary.Consultyourgassuppliertoaidyouin

determiningtheproperventingforyourwaterheaterfromthevent

tablesinthecurrenteditionoftheNationalFuelF󵐡l

GAS PIPING

Contact your local gas service company to ensure that adequate

gasservice is available and to review applicable installation codes

foryourarea.

SizethemaingaslineinaccordancewithTable3.Theguresshown

areforstraightlengthsofpipeat0.5in.W.C.pressuredrop,whichis

considerednormalforlowpressuresystems.Note:Fittingssuchas

elbows,teesandline regulatorswilladdtothepipepressure drop.

AlsorefertothecurrenteditionsoftheNationalFuelGasCode(NFPA

54)orNaturalGasandPropaneInstallationCode(CAN/CSAB149.1).

Makesuregassuppliedissametypelistedonmodelratingplate.The

inletgaspressuremustnotexceed14inchwatercolumn(2.6kPa)

fornaturalandpropane(L.P.)gas.Theminimuminletgaspressure

shownonratingplateisthatwhichwillpermitringatratedinput.

Ifthegascontrolvalveissubjectedtopressuresexceeding1/2pound

persquareinch(3.5kPa),thedamagetothegascontrolvalvecould

resultinareorexplosionfromleakinggas.

Ifthemaingaslineshut-offservingallgasappliancesisused,also

turn“off”thegasat each appliance. Leave allgas appliances shut

“off”untilthewaterheaterinstallationiscomplete.

Agaslineofsufcientsizemustberuntothewaterheater.Consult

thecurrenteditionofNationalFuelGasCodeANSIZ223.1/NFPA54

ortheNaturalGasandPropaneInstallationCodeCAN/CSAB149.1

andyourgassupplierconcerningpipesize.

Theremustbe:

• A readily accessible manual shut off valve in the gas supply line

servingthewaterheater,and

• Asedimenttrapaheadofthegascontrolvalvetohelppreventdirt

andforeignmaterialsfromenteringthegascontrolvalve.

• Aexiblegasconnectororagroundjointunionbetweentheshut

offvalveandcontrolvalvetopermitservicingoftheunit.

Besuretocheckallthegaspipingforleaksbeforelightingthewater

heater.Useasoapywatersolution,notamatchoropename.Rinse

offsoapysolutionandwipedry.

The minimum inlet gas pressure shown on the rating plate is that

whichwillpermitringattheratedinput.

TABLE 3. GAS SUPPLY LINE SIZES (IN INCHES)*

MAXIMUM CAPACITY OF PIPE IN CUBIC FEET PER HOUR

SEDIMENT TRAPS

Asedimenttrapshallbeinstalledasclosetotheinletofthewater

heateraspracticalatthetimeof water heater installation.The

sediment trap shall be either atee fitting with a capped nipple

inthe bottom outlet orother device recognized as an effective

sediment trap. If a tee fitting  is used, it shall be installed in

conformance with one of the methods of installation shown in

theFigures15and16.

Contaminantsinthegaslinesmaycauseimproperoperationof

thegascontrolvalvethatmayre sultinf ireorexplo si on.Before

attachingthegaslinebesurethatallgaspipeiscleanonthe

in s i de.Tot rapa ny dir torf o r eignmate r i ali ntheg ass upplylin e,

asedimenttrapmustbeincorporatedinthepiping.Thesediment

trapmustbereadilyaccessible.Installinaccordancewiththe

“GasPiping”section.RefertothecurrenteditionoftheNational

FuelGasCode,ANSIZ223.1/NFPA54ortheNaturalGasand

PropaneInstallationCodeCAN/CSAB149.1.

FLAMMABLE

WARNING:

If you do not follow these instructions exactly, a

fire or explosion may result causing property damage, personal

injury or loss of life.

BEFORE LIGHTING: ENTIRE SYSTEM MUST BE FILLED WITH WATER AND AIR PURGED FROM ALL LINES

WHAT TO DO IF YOU SMELL GAS

Do not try to light any appliance.

Do not touch any electric switch; do not use any

phone in your building.

Immediately call your gas supplier from a neighbor's

phone. Follow the gas supplier's instructions.

If you cannot reach your gas supplier, call the fire

department.

LIGHTING INSTRUCTIONS

TOP KNOB

FIGURE 'A'

"OFF" POSITION

OFF

PILOT

START UP CONDITIONS

DRAFT HOOD OPERATION

Check draft hood operation by performing a worst case

depressurization of the building. With all doors and windows

closed, and with all air handling equipment and exhaust fans

operating such as furnaces, clothes dryers, range hoods and

bathroomfans,amatchameshouldstillbedrawnintothedraft

hoodofthewaterheaterwithitsburnerring.Iftheameisnot

drawn toward the draft hood, shut off water heater and make

necessaryairsupplychangestocorrect.

CONDENSATION

Whenever the water heater is filled with cold water, some

condensatewillformwhiletheburnerison.Awaterheatermay

Shortrepeatedheatingcyclescausedbysmallhotwaterusescan

cause temperatures at the point of use to exceed the thermostat

settingby up to 30°F(16.7°C). If you experiencethis type of use

you should consider using lower temperature settings to reduce

scaldhazards.

Any water heater’s intended purpose is to heat water. Hot water

isneededforcleansing,cleaning,andsanitizing(bodies,dishes,

clothing). Untempered hot water can present a scald hazard.

Dependingonthetimeelement,andthepeopleinvolved(adults,

children, elderly, inrm, etc.) scalding may occur at different

temperatures.

HOTTERWATERCANSCALD:Waterheatersareintendedtoproduce

hot water.  Waterheated to a temperature which will satisfy space

heating,clothes washing,dishwashing,andothersanitizingneeds

canscaldandpermanently injure you upon contact.  Somepeople

aremorelikelytobepermanentlyinjured byhotwaterthanothers.

Theseincludetheelderly,children,theinrm,orphysically/mentally

handicapped.Ifanyoneusinghotwaterinyourhometsintooneof

thesegroupsorifthereisalocalcodeorstatelawrequiringacertain

temperaturewateratthehotwatertap,thenyoumusttakespecial

precautions. In addition to using the lowest possible temperature

settingthatsatisesyourhotwaterneeds,ameanssuchasamixing

valve should be used at the hot water taps used by these people or

atthewaterheater.Mixingvalvesareavailableatplumbingsupplyor

hardwarestores,seeFigure6.Followmanufacturer’sinstructionsfor

installationofthevalves.Beforechangingthefactorysettingonthe

thermostat,readthe“TemperatureRegulation”sectioninthismanual,

seeFigures17and18.

TEMPERATURE REGULATION

FOR YOUR INFORMATION

appeartobeleakingwheninfactthewateriscondensation.This

usuallyhappenswhen:

a.Anewwaterheaterislledwithcoldwaterforthersttime.

b.Bur n i n ggaspr o d u c e s w a t e r vap o r i n w a t e r h e a t e r s,pa r t i c u l a r l y

highefciencymodelswhereuetemperaturesarelower.

c.Largeamountsofhotwaterareusedinashorttimeandthe

rellwaterinthetankisverycold.

Moisturefromtheproductsofcombustioncondenseonthecooler

tank surfaces and form drops of water which may fall onto the

burnerorotherhotsurfacestoproducea“sizzling”or“frying”noise.

Excessive condensation can cause pilot outage due to water

runningdownthefluetubeontothemainburnerandputtingout

the pilot.

Neverallowsmallchildrentouseahotwatertap,ortodrawtheethe=p󷒡󻾡󽾣”

CHECKING GAS INPUT

Withthisheaterinoperation,determinewhetheritisreceivingthe

fullratedinput of gas.This may be donebytimingthegasmeter

andmeasuringgaspressurewithagaugeormanometer.Whenthe

heaterisoperatingatfullcapacity(fullgasinput)itshouldconsume

approximately1cubicfootofgasinthetimeshowninTable5.

TABLE 5. INPUT CHECK TIME REQUIRED

TO CONSUME 1 CU. FT. OF GAS

Model Type of Gas

BTU Per

Cu. Ft.

Approx. Time Required To

Consume 1 Cu. Ft. of Gas

BL-80

BL-100

Natural 1050 50.3sec.

Use this formula to “clock” the meter.  Be sure that other gas

consumingappliancesarenotoperatingduringthisinterval.

3,600XH=Btu/Hr

 T=Timeinsecondsneededtoburnonecubicfootofgas.

 H=HeatingvalueofgasinBtu’spercubicfootofgas.

 Btu/Hr=Actualheaterinputrate.

 Example:

 T=50.3seconds/ft

 H=1,050Btu/ft

(naturalgas)

 Btu/Hr=?

3,600X1,050=75,100Btu/Hr(22.0kW)

50.3

Comparetheactual input ratetothatgiven on the heater’srating

plate.Intheexample,theBL-100’sfullinputrateshouldbe75,100

Btu/Hrfornaturalgas.

Because of the suddenness and amount of water, condensation

watermaybediagnosedasa“tankleak”.Afterthewaterinthetank

warmsup(a0󾺠M

PERIODIC MAINTENANCE

VENTING SYSTEM INSPECTION

Atleastonceayearavisualinspectionshouldbemadeoftheventing

system.Youshouldlookfor:

1. Obstructions which could cause improper venting. The

 combustionandventilationairowmustnotbeobstructed.

2. Damage or deterioration which could cause improper venting

 orleakageofcombustionproducts.

3. Rustedakesaroundtopofwaterheater.

Be sure the vent piping is properly connected to prevent escape

ofdangerousuegaseswhichcouldcausedeadlyasphyxiation.

Obstructions and deteriorated vent systems may present serious

health risk or asphyxiation.

Chemical vapor corrosion of the ue and vent system may occur

if air for combustion contains certain chemical vapors. Spray can

propellants, cleaning solvents, refrigerator and air conditioner

refrigerants,swimmingpoolchemicals,calciumandsodiumchloride,

waxes,bleachandprocesschemicalsaretypicalcompoundswhich

arepotentiallycorrosive.

Ifafterinspectionofventsystemyoufoundsootingordeterioration,

somethingiswrong.Callthelocalgasutilitytocorrectproblemand

cleanorreplacetheueandventingbeforeresumingoperationof

water heater.

BURNER INSPECTION

Flood damage to a water heater may not be readily visible or

immediatelydetectable.However,overa period oftimeaooded

water heater will create dangerous conditions which can cause

DEATH, SERIOUS BODILY INJURY, OR PROPERTY DAMAGE.

Contactaqualiedinstallerorservicetechniciantoreplaceaooded

waterheater.Donotattempttorepairtheunit!Itmustbereplaced!

Atleastonceayearavisualinspectionshouldbemadeofthemain

burnerandpilotburner,seeFigure19.Inspectburneramesthrough

viewport.Flamesshouldbeverysmallwithabluehazeandsmall

amountsofyellowororangeattheedges.Afterseveralminutesof

operationtheburnerscreenmayglowred.

You should ]

WhencheckingtheTemperature-PressureReliefValveoperation,

makesurethat(1)nooneisinfrontoforaroundtheoutletofthe

Temperature-PressureReliefValvedischargeline,and(2)thatthe

waterdischargewillnotcauseanypropertydamage,asthewater

maybeextremelyhot.Usecarewhenoperatingvalveasthevalve

maybehot.

Tocheckthereliefvalve,lifttheleverattheendofvalveseveraltimes,

seeFigure21.Thevalveshouldseatproperlyandoperatefreely.

Ifaftermanuallyoperatingthevalve,itfailstocompletelyresetand

continuesto release water,immediately close thecoldwaterinlet

to the water heaterand drain thewater heater, see DrainingAnd

Flushingonpage24.ReplacetheTemperature-PressureReliefValve

with a properly rated/sized new one, see Temperature-Pressure

ReliefValveonpage11forinstructionsonreplacement.

DISCHARGE PIPE

TEMPERATURE-PRESSURE

RELIEF VALVE

FIGURE 21.

IftheTemperature-PressureReliefValveonthewaterheaterweeps

ordischargesperiodically,thismaybeduetothermalexpansion.

NOTE:Excessivewaterpressureisthemostcommoncauseof

Temperature-Pressure Relief Valve leakage. Excessive water

systempressure is most oftencaused by “thermal expansion”

ina“closedsystem.”SeeClosedWaterSystemsandThermal

Expansiononpage11.TheTemperature-PressureReliefValve

isnotintendedfortheconstantreliefofthermalexpansion.

Temperature-Pressure Relief Valve leakage due to pressure

build up in a closed system that does not have a thermal

expansion tank installed is not covered under the limited

warranty. Thermal expansion tanks must be installed on all

closedwatersystems.

DO NOT PLUG THE TEMPERATURE-PRESSURE RELIEF

VALVE OPENING. THIS CAN CAUSE PROPERTY DAMAGE,

SERIOUS INJURY OR DEATH.

Explosion Hazard

Temperature-Pressure Relief Valve

must comply with ANSI Z21.22-

CSA 4.4 and ASME code.

Properly sized temperature-

pressure relief valve must be

installed in opening provided.

Can result in overheating and

excessive tank pressure.

Can cause serious injury or death.

RECOMMENDED PROCEDURE FOR PERIODIC

REMOVAL OF LIME DEPOSITS FROM TANK TYPE

COMMERCIAL WATER HEATERS

Theamountofcalciumcarbonate(lime)releasedfromwateris

indirectproportiontowatertemperatureandusage,seechart.

Thehigherthewatertemperatureorwaterusage,themorelime

depositsaredroppedoutofthewater.Thisisthelimescalewhich

formsinpipes,heatersandoncookingutensils.

INSTALLEDINSUITABLEAREA:Toinsuresufficientventilation

and combustion air supply, proper clearances from the water

heater must be maintained. See Facts to ConsiderAboutThe

Location section. Combustible materials such as clothing,

cleaningmaterials,orflammableliquids,etc.must

Limeaccumulationnotonly reduces the life of the equipment but

alsoreducesefciencyoftheheaterandincreasesfuelconsumption.

The usage of water softening equipment greatly reduces the

hardness of the water. However, this equipment does not always

removeallofthehardness(lime).Forthisreasonitisrecommended

thataregularschedulefordelimingbemaintained.

Thetimebetweencleaningwillvaryfromweekstomonthsdepending

uponwaterconditionsandusage.

Thedepthoflimebuildupshouldbemeasuredperiodically.Heaters

equipped with cleanouts will have about 2” of lime buildup when

theleveloflimehasreachedthebottomofthecleanoutopening.A

schedulefordelimingshouldthenbesetup,basedontheamount

oftimeitwouldtakefora1”buildupoflime.Itisrecommendedthat

thewaterheaterinitiallybeinspectedafter6months.

Example1:

Initial inspection after 6 months shows 1/2” of lime accumulation.

Therefore,theheatershouldbedelimedonceayear.

Example2:

Initialinspectionafter6monthsshows2”oflimeaccumulation.

Therefore,theheatershouldbedelimedevery3months.

FIGURE 22.

DELIMING SOLVENTS

UN•LIME is recommended for deliming. UN•LIME is a patented

foodgradeacidwhichissafetohandleanddoesnotcreatethe

harmfulfumeswhichareassociatedwithotherproducts.

UN•LIMEmaybeobtainedfromyourdealer,distributororwater

heatermanufacturer.OrderPartNumber9005416105,1gallon,

packed 4 gallons per case or Part Number 9005417105, 5

galloncontainer.

NOTE:Un•LimeisnotavailableforuseinCanada.

Hydrochloric base acids are not recommended for use on glass

lined tanks.

Observehandlinginstructionsonlabelofproductbeingused.

TANK CLEANOUT PROCEDURE

Thefollowingpracticeswillensurelongerlifeandenabletheunitto

operateatitsdesignedefciency:

1. Onceamonththeheatershouldbeushed.Openthedrainvalve

andallowtwogallonsofwatertodrainfromtheheater.Inletwater

valveshouldremainopentomaintainpressureintank.

2. Acleanoutopeningisprovidedforperiodiccleaningofthetank.

Gasmustbeshutoffandheaterdrainedbeforeopeningcleanout.

Tocleanheaterthroughcleanoutopening,proceedasfollows:

1. Drain heater.

4. Putcapwithmaleadapterbackonthecontainerandslide3/4”

hoseover endofmaleadapter andfastenin placeusinghose

clampprovided.

DELIME USING FLO-JUG METHOD

5. Slidethehoseclampoverendofhoseandslidehoseoverthe

male adapter in the water heater drain opening and secure in

placeusinghoseclamp.

6. Liftcontainertothe“Pour”Positionbeingcarefultokeepthevent

in the handle above the liquid level and pour the UN•LIME into

the heater.

7. Lowercontainer,youmayhavetoplacethecontaineronitsempty

cartontopreventtheUN•LIMEfromowingbackintothecontainer.

8. LetUN•LIMEremainintheheaterfor5minutesandthenlower

thecontainertothe“Drain”Position.

9. Deliming activity is indicated by foaming on the surface of the

UN•LIME.Ifthereisdelimingactivity,repeatsteps6thru8.

Normally,lime removal will be completed within onehour. Severe

build-upoflimemaytakelongerthananhourtocompletedescaling.

Note:TocheckUN•LIMEforcontinueduse,placesomescaleorwhite

chalkinaglasswithasmallamountofUN•LIME.Ifthematerialis

vigorouslydissolvedbythe UN•LIME, it canbereused;ifnot,the

UN•LIMEshouldbereplaced.

Ifthetemperature-pressurereliefvalveontheapplianceweepsor

dischargesperiodically,thismaybeduetothermalexpansion.You

mayhaveacheckvalveinstalledinthewaterlineorawatermeter

with a check valve. Consult your local water supplier or service

technicianfor  further information. Do not plug the temperature-

pressurereliefvalve.

DRAINING AND FLUSHING

It is recommended that the water heater storage tank be

drained and ushed every 6 months to reduce sediment

buildup.Thewaterheatershouldbedrainedifbeingshutdown

during freezing temperatures. See Installation Considerations

inthismanualforthelocationofthewaterheatercomponents

describedbelow.

TROUBLESHOOTING GUIDELINES

Theseguidelinesshouldbeutilizedbyaqualiedserviceagent.

 Problem Cause Solution

WATER PIPING DIAGRAMS

October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit www.hotwater.com. AOSCG61130 | PAGE 1 of 1

A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

NOTES:

1. Preferred piping diagram.

2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.

3. Service valves are shown for servicing unit. However, local codes shall govern their usage.

4. The Tank Temperature Control should be wired to and control the pump between the water heater(s) and the storage tank(s).

5. The water heater’s operating thermostat should be set 5 degrees F higher than the Tank Temperature Control.

SINGLE FLUE - (1 UNIT)

LEGEND

TEMPERATURE & PRESSURE

RELIEF VALVE

PRESSURE RELIEF VALVE

CIRCULATING PUMP

TANK TEMPERATURE CONTROL

DRAIN

FULL PORT BALL VALV

TEMPERATURE GAGE

WATER FLOW SWITCH

CHECK VALVE

WARNING: THIS DRAWING SHOWS SUGGESTED

PIPING CONFIGURATION AND OTHER DEVICES;

CHECK WITH LOCAL CODES AND ORDINANCES

FOR ADDITIONAL REQUIREMENTS.

October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit ww w.hotwater.com. AOSCG61140 | PAGE 1 of 1

A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

NOTES:

1. Preferred piping diagram.

2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.

3. Service valves are shown for servicing unit. However, local codes shall govern their usage.

4. The Tank Temperature Control should be wired to and control the pump between the water heater(s) and the storage tank(s).

5. The water heater ’s operating thermostat should be set 5 degrees F higher than the Tank Temperature Control.

SINGLE FLUE - (1 UNIT) WITH VERTICAL STORAGE TANK

October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit ww w.hotwater.com. AOSCG61150 | PAGE 1 of 1

A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

NOTES:

1. Preferred piping diagram.

2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.

3. Service valves are shown for servicing unit. However, local codes shall govern their usage.

4. The Tank Temperature Control should be wired to and control the pump between the water heater(s) and the storage tank(s).

5. The water heater ’s operating thermostat should be set 5 degrees F higher than the Tank Temperature Control.

SINGLE FLUE - (1 UNIT) WITH HORIZONTAL STORAGE TANK

October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit www.hotwater.com. AOSCG61160 | PAGE 1 of 1

A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

NOTES:

1. Preferred piping diagram.

2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.

3. Service valves are shown for servicing unit. However, local codes shall govern their usage.

4. The Tank Temperature Control should be wired to and control the pump between the water heater(s) and the storage tank(s).

5. The water heater’s operating thermostat should be set 5 degrees F higher than the Tank Temperature Control.

SINGLE FLUE - (1 UNIT) WITH MIXING VALVE TWO TEMPERATURE

October 2009 | Printed in U.S.A. | © A. O. Smith For Technical Information and Automated Fax Service, call 800-527-1953 or visit ww w.hotwater.com. AOSCG61170 | PAGE 1 of 1

A. O. Smith Corporation reserves the right to make product changes or improvements without prior notice.

NOTES:

1. Preferred piping diagram.

2. The temperature and pressure relief valve setting shall not exceed pressure rating of any component in the system.

3. Service valves are shown for servicing unit. However, local codes shall govern their usage.

4. The Tank Temperature Control should be wired to and control the pump between the water heater(s) and the storage tank(s).

5. The water heater ’s operating thermostat should be set 5 degrees F higher than the Tank Temperature Control.

SINGLE FLUE - (2 UNITS)

LEGEND

TEMPERATURE & PRESSURE

RELIEF VALVE

PRESSURE RELIEF VALVE

CIRCULATING PUMP

TANK TEMPERATURE CONTROL

DRAIN

FULL PORT BALL VALV

TEMPERATURE GAGE

WATER FLOW SWITCH

CHECK VALVE

WARNING: THIS DRAWING SHOWS SUGGESTED

PIPING CONFIGURATION AND OTHER DEVICES;

CHECK WITH LOCAL CODES AND ORDINANCES

FOR ADDITIONAL REQUIREMENTS.

SINGLE FLUE

TEMPERATURE & PRESSURE

RELIEF VALVE

PRESSURE RELIEF VALVE

CIRCULATING PUMP

TANK TEMPERATURE CONTROL

DRAIN

FULL PORT BALL VALV

TEMPERATURE GAGE

WATER FLOW SWITCH

CHECK VALVE

WARNING: THIS DRAWING SHOWS SUGGESTED

PIPING CONFIGURATION AND OTHER DEVICES;

CHECK WITH LOCAL CODES AND ORDINANCES

FOR ADDITIONAL REQUIREMENTS.

NOTES

LIMITED WARRANTY

EFFECTIVE

For 3 Years, in t he event of a tank leak, we will repair or, at our

discret ion, replace t he defe cti ve wat er heat er.

For 1 Year, in t he e vent o f part f ailure, we will repair or, at our

discret ion, replac e t he def ecti ve part .

We warrant this product against def ects in materials or

workmans hip as described in t his document i f installed wit hin

the United Sta tes or Canada and prov ided t he product remains

at its original plac e o f installat ion.

Warranty co v erage begins the date of installation O R the dat e of

500 Tennessee Waltz Pkwy., Ashland City, TN 37015

TechnicalSupport:800-527-1953•Parts:800-433-2545

AO Smith BL-80 100 Conservationist 74-Gallon Ultra-Low NOx High Recovery Commercial Gas Water Heater

Product's Documents

Manual - CONSERVATIONIST® ULTRA-LOW NOX Manual (100228342)

Specifications

AO Smith BL-80 100 Questions and Answers