Takagi T-H3J-DV User manual

Gas Tankless Water HeaterTM
Suitable for potable water heating and space-heating
Please refer to local codes for space-heating compliance.
T-H3-DV model /
540H only
If you have any questions, please
call 1-888-479-8324
WARNING
- 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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.
- Installation and service must be performed
by a qualified installer, service agency or the
gas supplier.
On-Demand Water Heater
Installation Manual and Owner’s Guide
ANSI Z21.10.3 and CSA 4.3
If the information in these
instructions is not followed
exactly, a fire or explosion may
result causing property damage,
personal injury or death.
FEATURING
 • ENDLESSHOTWATER
 • ON-DEMANDUSAGE
 • COMPACT,SPACESAVING
 • ENERGYCONSERVATION
 • COMPUTERIZEDSAFETY
 • NOPILOTLIGHT
 • EASY-LINKSYSTEMAND
MULTI-UNIT SYSTEM
T-H3-DV model / 540H only
Models
T-H3J-DV / 240H
T-H3S-DV / 340H
T-H3-DV / 540H

2Page
Contents
CONTENTS
Installation Manual
SPECIFICATIONS.......................................................................................................................... 4
INTRODUCTION .......................................................................................................................... 5
SAFETY GUIDELINES.................................................................................................................... 6
INSTALLATION............................................................................................................................. 7
General.....................................................................................................................................7
Clearances................................................................................................................................9
Included Accessories...............................................................................................................9
Optional Items........................................................................................................................9
Warning for Installations........................................................................................................11
High-altitudeInstallations......................................................................................................12
VentingInstructions...............................................................................................................13
Gas supply and gas pipe sizing...............................................................................................20
Water Connections................................................................................................................22
Condensate drain..................................................................................................................23
ElectricalConnections............................................................................................................25
Easy-linkSystem.....................................................................................................................26
Multi-unitSystem...................................................................................................................30
APPLICATIONS............................................................................................................................31
INITIALOPERATION...................................................................................................................32
Owner's Guide
OPERATINGSAFETY .................................................................................................................. 34
NORMALOPERATION ............................................................................................................... 36
TemperaturecontrollerandRemotecontroller.....................................................................36
General...................................................................................................................................36
Temperaturesettings.............................................................................................................37
Temperature table of controller.............................................................................................37
Additionalfeatures.................................................................................................................38
TemperaturesettingsonthePCB(Withoutremotecontroller)............................................39
Flow.......................................................................................................................................40
Freeze protection system.......................................................................................................40
Maintenance and service.......................................................................................................41
Unit Draining and Filter Cleaning...........................................................................................41
TROUBLESHOOTING...................................................................................................................42
General...................................................................................................................................42
Error Codes...........................................................................................................................44
COMPONENTSDIAGRAM...........................................................................................................47
PARTSLIST.................................................................................................................................51
OUTPUTTEMPERATURECHART................................................................................................54
LIMITEDWARRANTY..................................................................................................................55

3Page
Installaon Manual
Installation Manual
CONGRATULATIONS
Congratulationsandthankyouforchoosingourtanklesswaterheater.
Beforeuse,werecommendthatyoureadthroughthissafetymanual
carefully.Pleaserefertothebackofthemanualfordetailsaboutthe
warranty.Keepthismanualforfuturereference.
If you lose the manual, contact the manufacturer or your local
distributor. When you call, please tell us the model number and the
serial number of your unit written on the rating plate of the water
heater.

4Page
SPECIFICATIONS
*275790pa(40psi)oraboveisrecommendedformaximumflow.
**TheManifoldPressureisthefactorysettingandgenerallyshould not need adjustment.
NOTE:
• Checktheratingplatetoensurethisproductmatchesyourspecifications.
• InaccordancewithCSA4.3,COemissiondoesnotexceed400ppmfornormalinput.
• The manufacturer reserves the right to discontinue, or change at any time, specifications or designs
without notice and without incurring obligation.
Specicaons
Installaon Manual
Model T-H3J-DV / 240H T-H3S-DV / 340H T-H3-DV / 540H
Natural Gas Input
(OperatingRange) BTU/h Min.: 15,000
Max.: 160,000
Min.: 15,000
Max.: 180,000
Min.: 15,000
Max.: 199,000
Propane Input
(OperatingRange) BTU/h Min.: 13,000
Max.: 160,000
Min.: 13,000
Max.: 180,000
Min.: 13,000
Max.: 199,000
Gas Connection 3/4"NPT
Water Connections 3/4"NPT
Water Pressure* MPa
(psi) 0.1-1(15-150)
Natural gas
Inlet Pressure
kPa
("W.C.)
Min.1.24(5.0)
Max.2.61(10.5)
Propane
Inlet Pressure
MPa
("W.C.)
Min.1.99(8.0)
Max.3.48(14.0)
Manifold
Pressure**
Natural
Gas
Pa
("W.C.)
373
(1.50)
610
(2.45)
734
(2.95)
Propane Pa
("W.C.)
523
(2.10)
672
(2.7)
821
(3.3)
Weight kg(lbs.) 26.3(58) 26.3(58) 26.8(59)
Dimensions mm H 570 x W 450 x D 272
H 22.4 x W 17.7 x D 10.7
inch
Ignition Electric Ignition
Electric
Supply VAC / Hz 120 / 60
Consumption
Operation W / A 72.7 / 0.61 78.2 / 0.65 89.0 / 0.74
Standby W / A 3.1 / 0.03 3.1 / 0.03 4.2 / 0.04
Freeze-
Protection W / A 174 / 1.5 174 / 1.5 175 / 1.5

5Page
INTRODUCTION
• This manual provides information necessary for the installation, operation, and maintenance
ofthewaterheater.
• Themodeldescriptionislistedontheratingplatewhichisattachedtothesidepanelofthe
waterheater.
• Pleasereadallinstallationinstructionscompletelybeforeinstallingthisproduct.
• If you have any problems or questions regarding this equipment, consult the manufacturer or
its local representative.
• Thisequipmentisanon-demand,tanklesswaterheaterdesignedtoefficientlysupplyendless
hotwaterforyourneeds.
• These high-efficiency models have a built-in secondary heat exchanger that absorbs latent
heat from the exhaust gas.
• The T-H3J-DV / 240H, T-H3S-DV / 340H and T-H3-DV / 540H models are only to be installed
indoors.
• Theprinciplebehindtanklesswaterheatersissimple:
 *Thisdiagramillustratestanklesswaterheaterdesignconceptsonlyanddoesnotaccurately
representthewaterheater’sphysicaldescription.
1. Ahotwatertapisturnedon.
2. Water enters the heater.
3. Thewaterflowsensordetectsthewaterflow.
4. The computer initiates the fan motor and sends a signal to the igniter to create an ignition spark.
5. Thegasignitesandflamesappearwithintheburnerchamber.
6. Water circulates through the heat exchanger and then gets hot.
7. Usingthermistorstomeasuretemperaturesthroughoutthewaterheater,thecomputermodulates
thegasandwatervalvestoensureproperoutputwatertemperature.
8. Whenthetapisturnedoff,theunitshutsdown.
Introducon
Installaon Manual
Exhaust
Secondary
heat exchanger
Intake port
Condensate
drain port
Coldwaterinlet
Gas
Hotwateroutlet
Computer board Fan motor
Gas valves
Thermistor
Burners
Thermistor
Bypassvalve
Primary
heat exchanger
Exhaust thermistor
Water control valve
Thermistor
Flowsensor

6Page
SAFETY GUIDELINES
SAFETY DEFINITION
GENERAL
1. Followalllocalcodes,orintheabsenceoflocalcodes,followthemostrecenteditionofCSAB149.1
NaturalGas,PropaneInstallationCode.
2. Properlygroundtheunitinaccordancewithalllocalcodesorintheabsenceoflocalcodes,withCSA
standardC22.1CanadaElectricalCodePart1.
3. Carefullyplanwhereyouintendtoinstallthewaterheater.Pleaseensure:
•Yourwaterheaterwillhaveenoughcombustibleairandproperventilation.
•Locateyourheaterwherewaterleakagewillnotdamagesurroundingareas.(pleasereferto
p.8.)
4. Check the rating plate for the correct GAS TYPE, GAS PRESSURE, WATER PRESSURE and ELECTRIC
RATING.
*If this unit does not match your requirements, do not install and consult with the manufacturer.
5. Ifanyproblemshouldoccur,turnoffallhotwatertapsandturnoffthegas.Thencallatrained
technician or the Gas Company or the manufacturer.
WARNING
Indicatesanimminentlyhazardoussituationwhich,ifnotavoided,couldresult
in death or serious injury.
CAUTION
Indicatesanimminentlyhazardoussituationwhich,ifnotavoided,couldresult
in minor or moderate injury.
Safety Guidelines
Installaon Manual
Indicatesanimminentlyhazardoussituationwhich,ifnotavoided,willresultin
death or serious injury.
DANGER
WARNING
• Watertemperaturesover52°C(125°F)cancausesevereburnsinstantlyor
deathfromscalding.Thewatertemperatureissetat49°C(120°F)fromthe
factory to minimize any scalding risk. Before bathing or showering always
checkthewatertemperature.
• Do not store or use gasoline or other flammables, vapors, or liquids in the
vicinity of this appliance.
• Donotreversethewaterand/orgasconnectionsasthiswilldamagethegas
valves and can cause severe injury or death.  Follow the diagram on p. 22
wheninstallingyourwaterheater.
• Do not use this appliance if any part has been in contact with or been
immersed in water.  Immediately call a licensed plumber, a licensed gas
fitter, or a professional service technician to inspect and/or service the unit if
necessary.
• Donotdisconnecttheelectricalsupplyiftheambienttemperaturewilldrop
below freezing.  The Freeze Protection System only works if the unit has
electrical power.  The warranty will not be covered if the heat exchanger
is damaged due to freezing.  Refer to the section on the Freeze Protection
System on p. 40 for more information.

7Page
INSTALLATION
GENERAL
1. Followalllocalcodes,orintheabsenceoflocalcodes,followthemostrecenteditionofCSAB149.1
NaturalGas,PropaneInstallationCode.
2. Allgaswaterheaters requirecareful andcorrectinstallationtoensuresafeand efficient operation.
Thismanualmustbefollowedexactly.Readthe“SafetyGuidelines”section.
3. The manifold gas pressure is preset at the factory. It is computer controlled and should not need
adjustment.
4. Maintain proper space for servicing. Install the unit so that it can be connected or removed easily.
Refertothe"Clearances"sectiononp.9forproperclearances.
5. Thewaterheatermustbeinstalledinalocationwheretheproperamountofcombustibleairwillbe
availabletoitatalltimeswithoutobstructions.
6. Theelectricalconnectionrequiresameansofdisconnection,toterminatepowertothewaterheater
for servicing and safety purposes.
7. Donotinstalltheunitwheretheexhaustventispointingintoanyopeninginabuildingorwherethe
noise may disturb your neighbors. Make sure the vent termination meets the required distance by
localcodefromanydoorwayoropeningtopreventexhaustfromenteringabuilding.(refertop.18.)
8. Particles from flour, aerosols, and other contaminants may clog the air vent, build up and reduce
thefunctionsoftherotatingfan,causeimproperburningofthegas,orcausedamagetothewater
heater.Regularlyensurethattheareaaroundtheunitisdust-ordebris-free.Regularmaintenanceis
recommended for these types of environment.
9. T-H3J-DV / 240H, T-H3S-DV / 340H, and T-H3-DV / 540H models are to be installed indoors only.
Theseunitsareequippedwithathermistorandhi-limitswitchfortheexhaustgas,detectingexcess
temperatures within the flue and enabling the unit to safely stop operations if needed.  These
componentsarealwaysmonitoringexhaustgasconditionsinordertopreventheatdamagetoPVC,
CPVCorPolypropylene(Plastic)ventingifPVC,CPVCorPolypropyleneis used.
 Iftheexhaustgastemperatureexceeds60°C(140°F),thesecomponentswillenabletheunittosafely
stop operations.
•Thesemodelsrequirea3"or4”make-upintakeairsupplypipe.Theintakepipemustbesealed
airtight.
•AirsupplypipecanbemadeofPVC,CPVCorPolypropylene,corrugatedstainlesssteel,or
Category lll / IV stainless steel.
•Sidewallventingisrecommendedforthesemodels.Verticalventing(rooftermination)is
acceptable.
•The manufacturer recommends running the exhaust vent and the intake pipe as parallel as
possible.
Installaon
Installaon Manual

8Page
INCLUDED ACCESSORIES
OPTIONAL ITEMS
• Installation and service must be performed by a qualified installer (for
example, a licensed plumber or gas fitter), otherwise the warranty will be
void.
• The installer (licensed professional) is responsible for the correct installation
of the water heater and for compliance with all national, state/provincial,
and local codes.
• The manufacturer does not recommend installing the water heater in a pit or
location where gas and water can accumulate.
• Donothavetheventterminalpointingtowardanyoperatingwindow,door,or
opening into a building.
• Do not install next to any source of airborne debris, such as a clothes dryer,
that can cause debris to be trapped inside the combustion chamber, unless the
system is direct-vented.
• The manufacturer does not recommend installing the water heater in an attic
due to safety issues.Ifyouinstallthewaterheaterinanattic:
• Makesuretheunitwillhaveenoughcombustionairandproper
ventilation.
• Keeptheareaaroundthewaterheaterclean.Whendustcollectsonthe
flamesensor,thewaterheaterwillshutdownonanerrorcode.
• Placetheunitforeasyaccessforserviceandmaintenance.
• Adrainpan,orothermeansofprotectionagainstwaterdamage,is
requiredtobeinstalledunderthewaterheaterincaseofleaks.
WARNING
• The warranty will not cover damage caused by water quality.
• Onlypotablewaterorpotablewater/glycolmixturescanbeusedwith
thiswaterheater.Donotintroducepoolorspawater,oranychemically
treatedwaterintothewaterheater.
• Waterhardnesslevelsmustnotexceed7grainspergallon(120ppm)for
singlefamilydomesticapplicationsormorethan4grainspergallon(70
ppm)forallothertypesofapplications.Waterhardnessleadstoscale
formationandmayaffect/damagethewaterheater.Hardwaterscaling
mustbeavoidedorcontrolledbyproperwatertreatment.
• WaterpHlevelsmustbebetween6.5and8.5
• Wellwatermustbetreated.
• Donotinstalltheunitwherewater,debris,orflammablevaporsmaygetinto
the flue terminal.
• Although the water heater is designed to operate with minimal sound, the
manufacturer does not recommend installing the unit on a wall adjacent to a
bedroom, or a room that is intended for quiet study or meditation, etc.
• Locateyourheaterclosetoadrainwherewaterleakagewillnotdodamage
tosurroundingareas.Aswithanywaterheatingappliance,thepotentialfor
leakage at some time in the life of the product does exist. The manufacturer
willnotberesponsibleforanywaterdamagethatmayoccur.Ifyouinstalla
drainpanundertheunit,ensurethatitwillnotrestrictthecombustionairflow.
CAUTION
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9Page
Maintain all clearances around
thewaterheater.
CLEARANCES
Installaon
Installaon Manual
INCLUDED ACCESSORIES
Checkthattheseitemsbelowareincludedwiththewaterheater.
Installation Manual
and Owner’s Guide
Communication Cable
T-H3-DV / 540H only
Qty: 1 Qty: 1
Model Top Bottom Front Back Sides
T-H3J-DV / 240H
T-H3S-DV / 340H
T-H3-DV / 540H
305 mm
(12in.)
305 mm
(12in.)
102 mm*
(4in.)
13 mm
(0.5in.)
51 mm
(2in.)
*610mm(24inches)recommendedformaintenance.
OPTIONAL ITEMS
#Model T-H3J-DV / 240H T-H3S-DV / 340H T-H3-DV / 540H
1. Temperature remote controller ✓✓✓
2. BackflowPreventer ✓✓✓
3. Pipecovers ✓✓✓
4. NeutralizerKit ✓✓✓
5. 3"ULCS636PVCConcentricTermination ✓✓✓
Back
Side
Front
Side
Top
Boom

10 Page
The pipe cover protects the plumbing pipes to
the water heater from unexpected adjustments.
Thispipecoverisfixedtothebottomofthewater
heater, which hides the plumbing and improves
thevisualaspectsofthewholeinstallationforthe
waterheater.
5. 3" ULC S636 PVC Concentric Termination: TH-CVPVC33
Used when terminating direct-vent (sealed-combustion)
systems,withdirect-ventmodelsthatrequirea76mm(3
in.)intakeanda76mm(3in.)exhaust.Thisconcentric
termination provides the convenience of only having to
makeonepenetrationthroughasidewallinsteadoftwo
separate penetrations for the intake and exhaust piping.
The termination includes a bird screen, restricting small
animals, pests, and foreign objects from entering into the
vent system.
NOTE: Concentric (single penetration) terminations are
only permitted for sidewall (horizontal) terminations.
Roof (vertical) terminations must use two separate
penetrations.
Installaon
Installaon Manual
The temperature remote controller has two
functions.Itallowstheoutputtemperaturefrom
thewaterheatertobeadjustedwithintherange
of 38 °C to 85 °C,anditalsoworksasadiagnostic
toolthatwillgiveaconciseerrorcodewhenever
thereisaproblemwiththeunit.Thetemperature
options are 38 °C (100 °F), 40 °C (105 °F), 43 °C
(110°F), 45 °C(115°F), 50 °C(120°F), 52 °C(125
°F), 55 °C(130°F), 57 °C(135°F), 60 °C(140°F), 63
°C(145°F), 65 °C(150°F), 68 °C(155°F), 70 °C(160
°F), 75 °C(165°F), 80 °C(175°F) and 85 °C(185°F).
See the troubleshooting section for information
on possible error codes.
1. Temperature remote controller:
TM-RE40
2. Backflow Preventer: TK-BF01
Thebackflowpreventerpreventsthebackflow
of air through the exhaust vent. This helps
prevent harmful exhaust gases from entering
the home, as well as helping to prevent the
unit from freezing in areas where cold air can
be blown or drawn into the exhaust system.
Install this vent damper in accordance with
the installation instructions and any applicable
codes.
3. Pipe covers: TH-PC03 4. Neutralizer kit: TH-NT01
The neutralizer assembly
neutralizes the condensate
(acidicwater)thatformsinthe
secondary heat exchanger of
thewaterheater.
It connects to the condensate
drain port of the water heater
by using connectors included
with the neutralizer kit.  Refer
to p. 24 for the details.

11 Page
WARNING FOR INSTALLATIONS
FOR YOUR SAFETY, READ BEFORE INSTALLATION:
Do not install the heater where water, debris or
flammable vapors may get into the flue terminal.
This may cause damage to the heater and void the
warranty.
Donothavetheventterminalpointingtoward
any opening into a building. Do not locate your
heaterinapitorlocationwheregasandwater
can accumulate.
Donotinstallthewaterheaterventterminator
within914 mm (3 ft.)of any air intake or building
opening.(Refertop.18.)
Do not install next to a dryer or any source
of airborne debris that can be trapped inside
the combustion chamber, unless the system is
direct vented.
ProhibitedProhibited
3ft.(914mm)
Canada
3ft.(914mm)
Canada
3ft.(914mm)
Canada
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12 Page
HIGH-ALTITUDE INSTALLATIONS
Check the elevation where your water heater is installed.  Set DIPswitches shown in the table below
depending on the altitude.
WARNING
DO NOT adjust any DIPswitches on the upper bank for the T-H3-DV / 540H.
Installaon
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NOTE: ThedarksquaresindicatethedirectiontheDIPswitchesshouldbesetto.
T-H3-DV / 540H
Computer board
LowerbankofDIPswitches
BankofDIPswitches
T-H3J-DV / 240H and T-H3S-DV / 340H
Computer board
0 (DEFAULT) Up to 2,500 ft Up to 5,000 ft Up to 7,500 ft Up to 10,100 ft
T-H3J-DV / 240H and
T-H3S-DV / 340H No. 3 : OFF
No. 4 : OFF
No. 5 : OFF
No. 3 : OFF
No. 4 : ON
No. 5 : OFF
No. 3 : OFF
No. 4 : OFF
No. 5 : ON
No. 3 : OFF
No. 4 : ON
No. 5 : ON
No. 3 : ON
No. 4 : ON
No. 5 : ON
T-H3-DV / 540H
(Lower bank of
DIPswitches) No. 2 : OFF
No. 3 : OFF
No. 4 : OFF
No. 2 : OFF
No. 3 : ON
No. 4 : OFF
No. 2 : OFF
No. 3 : OFF
No. 4 : ON
No. 2 : OFF
No. 3 : ON
No. 4 : ON
No. 2 : ON
No. 3 : ON
No. 4 : ON
OFF
ON
1 2 3 4 5 6 7 8 9 10
OFF
ON
1 2 3 4 5 6 7 8 9 10
OFF
ON
12345678910
OFF
ON
12345678910
OFF
ON
1 2 3 4 5 6
OFF
ON
1 2 3 4 5 6
OFF
ON
1 2 3 4 5 6
OFF
ON
1 2 3 4 5 6
OFF
ON
12345678910
OFF
ON
1 2 3 4 5 6
Altitude
DIPswitches

13 Page
VENTING INSTRUCTIONS
-General-
T-H3J-DV/240H,T-H3S-DV/340H,andT-H3-DV/540Hmodelsmustbeventedinaccordancewiththe
section“VentingofEquipment"ofthelatesteditionofCSAB149.1NaturalGasandPropaneInstallation
Code,aswellasapplicablelocalbuildingcodes.
The use of venting materials approved for Category III/IV appliances is recommended whenever
possible.  However, these models may also be vented with plastic pipe materials such as PVC, CPVC,
andPolypropylene.Fordetails,pleaserefertotheExhaustVent(Plasticvent)sectionfromp.14.Vent
installationsinCanadawhichutilizeplasticventsystemsmustuseventingthatisULCS636certified.
General rules for venting water heaters are:
• Placethewaterheaterascloseaspossibletotheventtermination.
• Theventcollarofthewaterheatermustbefasteneddirectlytoanunobstructedventpipe.
• Donotweldtheventpipetothewaterheater’sventcollar.
• Do not cut the vent collar of the unit.
• The vent must be easily removable from the top of the water heater for normal service and
inspection of the unit.
• Thewaterheaterventmustnotbeconnectedtoanyothergasapplianceorventstack.
• Avoid using an oversized vent pipe or using extremely long runs of the pipe.
• For rooftop venting, a rain cap or other form of termination that prevents rain water from
enteringintothewaterheatermustbeinstalled.
• Donotcommonventorconnectanyventfromotherappliancestothewaterheatervent.
General rules for vent terminations:
• Avoidlocatingthewaterheaterventterminationnearany air intake devices. These fans can
pickuptheexhaustflueproductsfromthewaterheaterandreturnthemtothebuilding.This
can create a health hazard.
• Locate the vent termination so that it cannot be blocked by any debris, at any time. Most codes
require that the termination be at least 305 mm (12 in.) above grade, but the installer may
determine that it should be higher, depending on the job site condition and applicable local
codes.
• A proper sidewall termination is recommended when the water heater is vented through a
sidewall.
• Regardingtheclearancesfromtheexhaustterminationtotheairinletoropening,refertop.18
and p. 19.
• Improper venting of this appliance can result in excessive levels of carbon
monoxidewhichcanresultinseverepersonalinjuryordeath.
• Improper installation can cause nausea or asphyxiation, severe injury or death
fromcarbonmonoxideandfluegasespoisoning.Improperinstallationwillvoid
productwarranty.
DANGER
When installing the vent system, all applicable national and local codes must be
followed.Ifyouinstallthimbles,firestopsorotherprotectivedevicesandthey
penetrateanycombustibleornoncombustibleconstruction,besuretofollowall
applicable national and local codes.
CAUTION
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14 Page
-DIPswitch settings for Vent length-
-Exhaust vent (Plasc vent)-
These models can be vented with a plastic vent which is made of PVC, CPVC, or polypropylene
(temperatureratedupto149°F).InCanada,plasticventingmustbecertifiedtoULCS636standards.
Item Material Canada
Exhaust pipe and
Fittings
Schedule40PVC
ULC S636 Certified
Materials Only
Schedule40CPVC
Polypropylene
PipeCement/Primer PVC
CPVC
NOTE:DoNOTUseCellularFoamCorePipe
102 mm (4") venting
T-H3J-DV / 240H
T-H3S-DV / 340H
T-H3-DV / 540H
(Upper bank of DIPswitches) Vent length
No. 6 : ON
No. 7 : OFF
No. 3 : ON
No. 4 : OFF
1.5 to 15.2 m
(5 to 50 ft)
(DEFAULT)
No. 6 : OFF
No. 7 : OFF
No. 3 : OFF
No. 4 : OFF
15.5 to 30.5 ft
(51 to 100 ft)
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8 9 10
OFF
ON
1 2 3 4 5 6 7 8 9 10
76 mm (3") venting
T-H3J-DV / 240H
T-H3S-DV / 340H
T-H3-DV / 540H
(Upper bank of DIPswitches) Vent length
No. 6 : ON
No. 7 : OFF
No. 3 : ON
No. 4 : OFF
1.5 to 6.1 m
(5 to 20 ft)
(DEFAULT)
No. 6 : OFF
No. 7 : OFF
No. 3 : OFF
No. 4 : OFF
6.4 to 12.2 m
(21 to 40 ft)
No. 6 : ON
No. 7 : ON
No. 3 : ON
No. 4 : ON
12.5 to 21.3 m
(41 to 70 ft)
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8 9 10
OFF
ON
1 2 3 4 5 6 7 8 9 10
OFF
ON
1 2 3 4 5 6 7 8
OFF
ON
1 2 3 4 5 6 7 8 9 10
SetDIPswitchesshowninthetablebelowdependingontheventlength.
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15 Page
• The maximum length of exhaust vent piping must not exceed 21.3 m (70 ft.) for 76 mm (3”)
venting,whichdependsontheelevationwherethewaterheaterisinstalled.30.5m(100ft.)
for102mm(4”)venting(deducting1.5m(5ft.)foreachelbowusedintheventingsystem).Do
notusemorethan5elbows.Seethetablebelow.
• Whenthehorizontalventrunexceeds1.5m(5ft.),supporttheventrunat0.9m(3ft.)intervals
withoverheadhangers.
-Plasc Venng Illustraons-
For details of the optional items, refer to the Installation manual for each Optional item.
Installaon
Installaon Manual
No. of Elbows
Max. Vertical or Horizontal (Total) Vent Length
76 mm (3") venting 102 mm (4") venting
Elevations up
to 3,000 ft
Elevations up
to 6,000 ft
Elevations up
to 10,100 ft
Elevations up
to 10,100 ft
021.3m(70ft.) 12.2m(40ft.) 7.6m(25ft.) 30.5m(100ft.)
119.8m(65ft.) 10.7m(35ft.) 6.1m(20ft.) 29.0m(95ft.)
218.3m(60ft.) 19.1m(30ft.) 4.6m(15ft.) 27.4m(90ft.)
513.7m(45ft.) N/A N/A 22.9m(75ft.)
Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
76mm(3in.) 521.3m(70ft.)
102mm(4in.) 530.5m(100ft.)
*For each elbow added, deduct 1.5 m (5 ft.) from max. vent length.
Excludesventterminators,terminationelbows,orraincaps
For details on the vent connection to these models, refer to p. 16.
Horizontal Installaon Diagram Vercal Installaon Diagram
Roof
Flashing
Roof
Fire stop
Wall
Connectbetweenexhaustventcollarandplascpiping.
Seethenextpageforinstrucons.

16 Page
<How to install plastic venting>
76 mm (3") vent connecon Diagram
From 76 mm (3") to 102 mm (4") vent connecon Diagram
-Exhaust vent (Stainless steel vent)-
This is a Category IV appliance and must be vented accordingly. The vent system must be sealed airtight.
All seams and joints without gasketsmustbesealedwithhighheatresistantsiliconesealantorULlisted
aluminum adhesive tape having a minimum temperature rating of 71 °C(160°F). For best results, a vent
system should be as short and straight as possible.
• These models are a Category IV appliance and must be vented accordingly with any 4” vent
approvedforusewithCategoryIII/IVorSpecialBHtypegasvent.
• The manufacturer recommends the “T-Vent” line manufactured by TAKAGI.(RefertoTakagi’s
“T-Vent”brochurefordetails.)However,thefollowingarealsoULlistedmanufacturers:ProTech
SystemsInc.(FasNSeal),Flex-LInc.,Z-FlexInc.(Z-VentIII),Metal-FabInc.,andHeat-FabInc.(Saf-T
Vent).
• Follow the vent pipe manufacturer’s instructions when installing the vent pipe.
• Do not common vent this appliance with any other vented appliance.(Donotterminatevent
intoachimney.Iftheventmustgothroughthechimney,theventmustrunallthewaythrough
thechimneywithCategoryIII/IVapprovedorSpecialBHventpipe.)
• The maximum length of exhaust vent piping must not exceed 30.5 m (100 ft.)(deducting1.5m
(5ft.)foreachelbowusedintheventingsystem).Donotusemorethan5elbows.
• Whenthehorizontalventrunexceeds1.5m(5ft.),supporttheventrunat0.9m(3ft.)intervals
withoverheadhangers.
Installaon
Installaon Manual
76mm(3”)
plascsocket
Exhaust vent collar
(Female)
76mm(3”)
plascstraightpipe
76mm(3”)
plascsocket
Intake vent collar
(Female)
76mm(3”)
plascstraightpipe
1. Connecta76mm(3")plasticsocket
directly on the exhaust and intake vent
collarofthewaterheater.
2. Connecta76mm(3”)plasticstraight
pipe to the plastic socket.
1. Connecta76mm(3")x102mm
(4")plasticreducerdirectlyonthe
exhaust and intake vent collar of
thewaterheater.
2. Connecta102mm(4”)plastic
straight pipe to the reducer.
102mm(4”)
plascstraightpipe
76mm(3")x102mm(4")
plascreducer
Exhaust vent collar
(Female)
Intake vent collar
(Female)
102mm(4”)
plascstraightpipe
76mm(3")x102mm(4")
plascreducer

17 Page
-Stainless steel Vent Illustraons-
<How to install stainless steel venting>
• Regardingtheclearancesfromtheexhaustterminaltotheairinletoropening,refertothe
nextfewpages.
• Followallventsystemmanufacturer’sinstructionsandalllocalcodes.
• Do not common vent or connect any vent from other appliances to these models vent.
• Use102mm(4”)CategoryIII/IVapprovedorSpecialBH,singleordoublewallstainlesssteel
vent pipe.
Horizontal Installaon Diagram
Wall
SidewallVent
Terminator
Vercal Installaon Diagram
Roof
Roof
Flashing
Fire stop
RainCap
102 mm (4") vent connecon Diagram
Connecta102mm(4")stainless
steel vent straight pipe directly on the
exhaust and intake vent collar of the
waterheater.
102mm(4”)stainless
steel vent straight pipe
Exhaust vent collar
(Female)
Intake vent collar
(Female)
102mm(4”)
stainless steel
vent straight
pipe
Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
102mm(4in.) 530.5m(100ft.)
*For each elbow added, deduct 1.5 m (5 ft.) from max. vent length.
No. of Elbows Max. Vertical or Horizontal Vent Length
030.5m(100ft.)
129.0m(95ft.)
227.4m(90ft.)
522.9m(75ft.)
Excludesventterminators,terminationelbows,orraincaps.
Installaon
Installaon Manual

18 Page
-Vent terminaon clearances-
Canada U.S.A
Direct vent and other
than Direct Vent
Direct
vent
Other than
Direct Vent
AClearance above grade, veranda, porch, deck, or
balcony 1 foot 1 foot 1 foot
B Clearancetowindowordoorthatmaybeopened 3 feet 1 foot
4feetfrombelowor
side opening. 1 foot
from above opening.
CClearancetopermanentlyclosedwindow * * *
D
Vertical clearance to ventilated soffit located above
theventterminatorwithinahorizontaldistance
of2feet(61cm)fromthecenterlineofthe
terminator
* * *
EClearance to unventilated soffit * * *
FClearance to outside corner * * *
GClearance to inside corner * * *
HClearance to each side of center line extended
above meter/regulator assembly 3 feet * *
IClearance to service regulator vent outlet 3 feet * *
J
Clearance to non-mechanical air supply inlet to
building or the combustion air inlet to any other
application
3 feet 1 foot
4feetfrombelowor
side opening. 1 foot
from above opening.
KClearance to mechanical air supply inlet 6 feet 3 feet 3 feet
LClearanceabovepavedsidewalkorpaveddriveway
located on public property 7 feet *7 feet
MClearance under veranda, porch deck, or balcony 1 foot * *
*ForclearancesnotspecifiedinCSA-B149.1,pleaseuseclearancesinaccordancewithlocalinstallationcodesand
the requirements of the gas supplier.
Installaon
Installaon Manual
INSIDECORNERDETAIL
V
Gas meter / regulator
V
V
V
V
V
V
V
V
V
X
X
X
Vent terminal
Air supply inlet
Areawhereisnotpermitted
G
A
E
D
B
L
C
F
B
B
B
BA
J
OPERABLE FIXED
CLOSED
B
H
M
K
OPERABLE
FIXED
CLOSED
I

19 Page
-For sidewall terminaons-
-For rooop terminaons-
Formultiplesidewallexhaustterminations(e.g.multi-unit
systems),anexhaustterminationmustbeatleast305mm
(1ft.)awayfromanotherexhausttermination.Anexhaust
termination must also be at least 610 mm (2 ft.) away
fromaninsidecorner.(iftheadjacentwallislessthan610
mm(2ft.)oflength,theminimumrequireddistanceaway
fromtheinsidecornerwillbeequaltothelengthofthat
adjacentwall.)
For multiple-unit, direct-vent sidewall terminations that
combine the intake and exhaust into a single penetration,
spaceeachdirect-ventterminationatleast305mm(1ft.)
awayfromeachother,nomattertheorientation.Adirect-
ventterminationmustalsobeatleast610mm(2ft.)away
fromaninsidecorner.(iftheadjacentwallislessthan610
mm(2ft.)oflength,theminimumrequireddistanceaway
fromtheinsidecornerwillbeequaltothelengthofthat
adjacentwall.)
For multiple-unit rooftop terminations (whether for standard or direct-vent installations) space all
exhaustandintaketerminationsinaccordancewithlocalcodes.Anexhaustterminationmustbespaced
fromawallorsurfaceinaccordancewithlocalcodesaswell.Intheabsenceofsuchacode,anexhaust
terminationmustbeahorizontaldistanceofatleast610mm(2ft.)awayfromawallorsurface.
Exhaust and/or
direct-vent sidewall
terminations should
be at least 610 mm
(2 ft.) away from an
opposite surface/
wall.Donotplacethe
termination directly
in front of an opening
into a building.
610 mm
(2ft.)
Exhaust
termination
Please follow all local and national codes in regards to proper termination
clearances. In the absence of such codes, the above clearances can be used as
guidelines. Local codes supersede these guidelines.
CAUTION
Installaon
Exhaust
termination
Inside
corner
305 mm
(1ft.)
610 mm
(2ft.)
305 mm
(1ft.)
Installaon Manual
A:Inaccordancewithlocalcodes
Air intake
A
Exhaustterminaon
A
A
A
A
Air intake
610 mm
(2)
Exhaust
terminaon
For direct-vent sidewall
terminationsthatusetwo
separate penetrations for
the intake and exhaust,
distance the intake and
exhaust terminations at
least915mm(3ft.)away
from each other, no
matter the orientation.
915
mm
(3ft.)
Air supply inlet
915 mm
(3ft.)
915 mm
(3ft.)
Exhaust
termination
Combined
intake and
exhaust
termination
Inside
corner
305 mm
(1ft.)
610 mm
(2ft.)
305 mm
(1ft.)

20 Page
GAS SUPPLY AND GAS PIPE SIZING
-General-
• The minimum and maximum inlet gas pressures are:
• Inlet gas pressure except the ranges in the table above will adversely affect performance.  These
pressuresaremeasuredwhenthewaterheaterisinfulloperation.
• Inlet gas pressure must not exceed the above maximum values; gas pressure above the specified range
willcausedangerousoperatingconditionsanddamagetotheunit.
• Untiltestingofthemaingaslinesupplypressureiscompleted,ensurethegaslinetothewaterheater
isdisconnectedtoavoidanydamagetothewaterheater.
-Gas connecons-
1. Installamanualgasshutoffvalvebetweenthewaterheaterandthegassupplyline.
2. When the gas connections are completed, it is necessary to perform a gas leak test either by applying
soapywatertoallgasfittingsandobservingforbubblesorbyusingagasleakdetectiondevice.
• Thewaterheateranditsindividualshutoffvalvemustbedisconnectedfromthegassupply
pipingsystemduringanypressuretestingofthatsystemattestpressuresinexcessof3.5kPa
(1/2psi).
• Thewaterheatermustbeisolatedfromthegassupplypipingsystembyclosingitsindividual
manual shutoff valve during any pressure testing of the gas supply piping system at test
pressuresequaltoorlessthan3.5kPa(1/2psi).
3. Alwayspurgethegaslineofanydebrisand/orwaterbeforeconnectingtothegasinlet.
Size the gas pipe appropriately to supply the necessary volume of gas required for
thewaterheaterusingCSAB149.1orlocalcodes.Otherwise,flowcapabilitiesand
outputtemperatureswillbelimited.
NOTICE
Gas type Inlet gas pressure
Natural Gas Min.1.24kPa(5.0”W.C.)–Max.2.61kPa(10.5”W.C.)
Propane Min.1.99kPa(8.0”W.C.)–Max.3.48kPa(14.0”W.C.)
• Check that the type of gas matches the rating plate first.
• Ensure that any and all gas regulators used are operating properly and
providing gas pressures within the specified range shown below. Excess gas
inlet pressure may cause serious accidents.
• Conversion of this unit from natural gas to propane or vise versa will void
all warranty.  Contact your local distributor to get the correct unit for your
gas type. The manufacturer is not liable for any property and/or personal
damage resulting from gas conversions.
CAUTION
Installaon
Installaon Manual