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.
540 (T-H3)
models only
If you have any questions, please
call or write to:
500 Tennessee Waltz Parkway
Ashland City, TN 37015
Toll Free: 1-877-737-2840
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
 • Satisfiesthe2012SCAQMDRule
1146.2 for Ultra-Low NOx
Emissions
 • EASY-LINKSYSTEMAND
MULTI-UNIT SYSTEM
(540 (T-H3) models only)
Models
• 240 Outdoor (T-H3J-OS)
• 340 Outdoor (T-H3S-OS)
• 540 Outdoor (T-H3-OS)
• 240 Indoor (T-H3J-DV)
• 340 Indoor (T-H3S-DV)
• 540 Indoor (T-H3-DV)

2Page
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
Ventinginstructions...............................................................................................................13
Gas supply and gas pipe sizing...............................................................................................23
Water connections................................................................................................................25
Condensate drain..................................................................................................................26
Electrical connections............................................................................................................28
Temperature remote controller............................................................................................29
Easy-Link System....................................................................................................................32
Multi-Unit System.................................................................................................................36
APPLICATIONS............................................................................................................................37
INITIALOPERATION...................................................................................................................39
Owner's Guide
OPERATINGSAFETY .................................................................................................................. 41
NORMALOPERATION ............................................................................................................... 43
TemperaturecontrollerandRemotecontroller.....................................................................43
General...................................................................................................................................43
Temperaturesettings.............................................................................................................44
Temperature table of controller.............................................................................................44
Additionalfeatures.................................................................................................................45
Temperature settings on the PCB (Without remote controller)............................................46
Flow.......................................................................................................................................47
Freeze protection system.......................................................................................................47
Maintenance and service.......................................................................................................48
Unit draining and filter cleaning...........................................................................................48
TROUBLESHOOTING...................................................................................................................49
General...................................................................................................................................49
Error codes............................................................................................................................51
COMPONENTSDIAGRAM...........................................................................................................54
PARTSLIST.................................................................................................................................58
OUTPUTTEMPERATURECHART................................................................................................61
LIMITEDWARRANTY..................................................................................................................62
Contents

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
Specicaons
Installaon Manual
SPECIFICATIONS
*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ANSIZ21.10.3,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.
Model 240
Indoor
(T-H3J-DV)
240
Outdoor
(T-H3J-OS)
340
Indoor
(T-H3S-DV)
340
Outdoor
(T-H3S-OS)
540
Indoor
(T-H3-DV)
540
Outdoor
(T-H3-OS)
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* psi
(MPa) 15 - 150 (0.1 - 1)
Natural gas
Inlet Pressure
" W.C.
(kPa)
Min. 5.0 (1.24)
Max. 10.5 (2.61)
Propane
Inlet Pressure
" W.C.
(kPa)
Min. 8.0 (1.99)
Max. 14.0 (3.48)
Manifold
Pressure**
Natural
Gas
" W.C.
(Pa)
1.50
(373)
1.70
(423)
2.45
(610)
2.1
(523)
2.95
(734)
2.70
(672)
Propane " W.C.
(Pa)
2.10
(523)
1.90
(473)
2.7
(672)
2.55
(635)
3.3
(821)
3.15
(784)
Weight lbs. (kg) 58 (26.3) 58 (26.2) 58 (26.3) 58 (26.2) 59 (26.8) 59 (26.9)
Dimensions inch H 22.4 x W 17.7 x D 10.7
H 570 x W 450 x D 272
mm
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 240 Indoor (T-H3J-DV), 340 Indoor (T-H3S-DV) and 540 Indoor (T-H3-DV) models are
only to be installed indoors. The 240 Outdoor (T-H3J-OS), 340 Outdoor (T-H3S-OS) and 540
Outdoor (T-H3-OS) models are only to be installed outdoors.
• 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
Thermistor
Bypass valve
Primary
heat exchanger
Exhaust thermistor
Water control valve
Thermistor
Flow sensor
Burners

6Page
SAFETY GUIDELINES
SAFETY DEFINITION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the most recent edition of the National
Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or CAN/CSA B149.1 Natural Gas, Propane Installation
Code in Canada.
2. Properly ground the unit in accordance with all local codes or in the absence of local codes, with the
National Electrical Codes: ANSI/NFPA 70 in the USA or CSA standard C22.1 Canadian Electrical Code
Part 1 in Canada.
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 125 °F (52 °C) can cause severe burns instantly or
death from scalding. The water temperature is set at 120 °F (49 °C) 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. 25
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. 47 for more information.

7Page
INSTALLATION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the most recent edition of the National
Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or CAN/CSA B149.1 Natural Gas, Propane Installation
Code in Canada.
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.20.)
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. The240Indoor(T-H3J-DV),340Indoor(T-H3S-DV),and540Indoor(T-H3-DV)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ABS,PVC,CPVC,orpolypropylene(Plastic)ventingifABS,PVC,CPVC,orpolypropylene
is used. If the exhaust gas temperature exceeds 140 °F, these components will enable the unit to
safely stop operations. (For the Outdoor model, these components are not available since there’s
no exhaust venting required.)
•TheIndoormodelrequiresa3"or4”make-upintakeairsupplypipe.Theintakepipemustbe
sealed airtight.
•AirsupplypipecanbemadeofABS,PVC,CPVC,polypropylene,corrugatedstainlesssteel,or
Categorylll/IVstainlesssteel.
•SidewallventingisrecommendedfortheIndoormodel.Verticalventing(rooftermination)is
acceptable.
•The manufacturer recommends running the exhaust vent and the intake pipe as parallel as possible.
10. The 240 Outdoor (T-H3J-OS), 340 Outdoor (T-H3S-OS), and 540 Outdoor (T-H3-OS) models only to be
installed outdoors and only in the area with mild, temperate climates.
The Outdoor model shall be wall-mounted or mounted on a stand. Locate the Outdoor model in an
open, unroofed area and maintain the following minimum clearances:
Thereisa3”clearancefromtheleftandrightsidesoftheunittocombustibleandnon-combustible
surfaces.
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
Installaon
Installaon Manual

9Page
Maintain all clearances around
the water heater.
CLEARANCES
Installaon
Installaon Manual
INCLUDED ACCESSORIES
Model Top Bottom Front Back Sides
240Indoor(T-H3J-DV)
340Indoor(T-H3S-DV)
540Indoor(T-H3-DV)
12 in.
(305 mm)
12 in.
(305 mm)
4 in.*
(102 mm)
0.5 in.
(13 mm)
2 in.
(51 mm)
240 Outdoor (T-H3J-OS)
340 Outdoor (T-H3S-OS)
540 Outdoor (T-H3-OS)
36 in.
(914 mm)
12 in.
(305 mm)
24 in.
(610 mm)
0.5 in.
(13 mm)
2 in.
(51 mm)
*24 inches recommended for maintenance.
OPTIONAL ITEMS
Back
Side
Front
Side
Top
Boom
Check that these items below are included with the water heater.
Installation manual
and owner’s guide
Temperature remote controller kit*
Outdoor models only
Bird screen
Indoor models only
Communication cable
540 (T-H3) models only
Qty:1 Qty:1
Qty:1
*Refertop.29.
Qty:2
#Model
240
Indoor
(T-H3J-DV)
240
Outdoor
(T-H3J-OS)
340
Indoor
(T-H3S-DV)
340
Outdoor
(T-H3S-OS)
540
Indoor
(T-H3-DV)
540
Outdoor
(T-H3-OS)
1. Temperature remote
controller ✓✓✓✓✓✓
2. 4" Backflow preventer
and F-F adaptor ✓✓✓
3. Pipe cover ✓✓✓✓✓✓
4. Neutralizer kit ✓✓✓✓✓✓
5.
Sidewall vent
terminator (Hood)
and Wall thimble ✓✓✓
6. 3"PVCconcentric
termination ✓✓✓

10 Page
Installaon
Installaon Manual
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.
The temperature remote controller has two
functions. It allows the output temperature
from the water heater to be adjusted within the
range of 100 °F to 185 °F, 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 100 °F, 105 °F, 110 °F,
115 °F, 120 °F, 125 °F, 130 °F, 135 °F, 140 °F, 145
°F, 150 °F, 155 °F, 160 °F 165 °F, 175 °F and 185 °F.
See the Troubleshooting Section for information
on possible error codes.
1. Temperature remote controller:
9008172005 (TM-RE40)
3. Pipe cover: 9008331005 (TH-PC03) 4. Neutralizer kit: 9007607005 (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.27
for the details.
6. 3" PVC concentric termination: 9007611005 (TH-CVPVC33)
Used when terminating direct-vent (sealed combustion)
systems, with Indoor models that require a 3 in. (76 mm)
intake and a 3 in. (76 mm) 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.
2. 4” Backflow preventer and F-F adaptor:
9007996005
There are two functions available for this
adaptor, which can be connected with the water
heater and NovaVent venting line and 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 adaptor in accordance with the
installation instructions that are packaged with
the adaptor and any applicable codes.
5. Sidewall vent terminator (Hood) and Wall thimble:
They are used when venting out through the wall. These terminations are special stainless steel
ventsforgasappliancesandareULlistedasCategoryII,IIIandIV.Fordifferentwallthicknesses,
therearetworangesoflengthsavailable.(RefertotheNovaVentbrochurefordetails.)Installthese
vent terminations in accordance with their installation instructions and any applicable local codes.
Covering wall thicknesses Part#
Terminator Hood 9007999005
Wall Thimble 4 - 7 in. 9008345005
Wall Thimble 5 - 10 in. 9008346005
Termination + Thimble 4 - 7 in. 9008004005
Termination + Thimble 5 - 10 in. 9008005005
Wall Thimble
Terminator Hood

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 this water heater under an
overhang less than 3 ft. (914 mm) from its top
or eaves. The area under an overhang must be
open to three sides (Outdoor models only).
Do not install the water heater vent terminator
within 1 ft. (305 mm) in the USA of any air intake
or building opening, and within 3 ft. (914 mm)
in Canada of any air intake or building opening
(Outdoor models only, refer to p. 20).
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)
1 ft. (305 mm) USA
3 ft. (914 mm) Canada
1 ft. (305 mm) USA
3 ft. (914 mm) Canada 1 ft. (305 mm) USA
3 ft. (914 mm) Canada
Installaon
Installaon Manual

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 540 (T-H3)
models.
Installaon
Installaon Manual
NOTE: The dark squares indicate the direction the DIPswitches should be set to.
540 (T-H3) models
Computer board
Lower bank of DIPswitches
Outdoor models
0 (DEFAULT) Up to 2,000 ft Up to 4,000 ft Up to 6,000 ft Over 6,000 ft
240 (T-H3J) and
340 (T-H3S) models 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 : ON
No. 4 : OFF
No. 5 : ON
Consult our
Technical
Services
at 1-877-
737-2840
540 (T-H3) models
(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 : ON
No. 3 : OFF
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
1 2 3 4 5 6 7 8 9 10
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
Altitude
DIPswitches
Bank of DIPswitches
240 (T-H3J) and 340 (T-H3S) models
Computer board
Indoor models
0 (DEFAULT) Up to 2,500 ft Up to 5,000 ft Up to 7,500 ft Up to 10,100 ft
240 (T-H3J) and
340 (T-H3S) models 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
540 (T-H3) models
(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
Altitude
DIPswitches
OFF
ON
12345678910
OFF
ON
1 2 3 4 5 6

13 Page
VENTING INSTRUCTIONS
For the 240 Indoor (T-H3J-DV), 340 Indoor (T-H3S-DV) and 540 Indoor (T-H3-DV) models
-General-
TheIndoormodelsmustbeventedinaccordancewiththesection“VentingofEquipment"ofthelatest
edition of the National Fuel Gas Code: ANSI Z223.1/NFPA 54 in the United States and/or Section 7 of the
CAN/CSA B149.1 Natural Gas and Propane Installation Code in Canada, as well as applicable local building
codes.
TheuseofventingmaterialsapprovedforCategoryIII/IVappliancesisrecommendedwheneverpossible.
However,theIndoormodelsmayalsobeventedwithplasticpipematerialssuchasABS,PVC,CPVC,or
polypropylene.  For details, please refer to the Exhaust Vent (ABS, PVC, CPVC, or polypropylene Vent)
Sectionfromp.15.VentinstallationsinCanadawhichutilizeplasticventsystemsmustuseventingthat
complies with ULC S636.
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 terminate vent into a chimney. If the vent must go through the chimney, the vent must
run all the way through the chimney with approved vent pipe.
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 12 in. (305 mm) above grade, but the installer may
determine if it should be higher depending on the job site condition and applicable 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.
20-22.
• 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
Installaon
Installaon Manual

14 Page
-DIPswitch settings for Vent length-
4" venting
Vent length 240 Indoor (T-H3J-DV)
340 Indoor (T-H3S-DV)
540 Indoor (T-H3-DV)
(Upper bank of DIPswitches)
5 to 50 ft
(DEFAULT) No. 6 : ON
No. 7 : OFF
No. 3 : ON
No. 4 : OFF
51 to 100 ft
No. 6 : OFF
No. 7 : OFF
No. 3 : OFF
No. 4 : OFF
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
3" venting
Vent length 240 Indoor (T-H3J-DV)
340 Indoor (T-H3S-DV)
540 Indoor (T-H3-DV)
(Upper bank of DIPswitches)
5 to 20 ft
(DEFAULT) No. 6 : ON
No. 7 : OFF
No. 3 : ON
No. 4 : OFF
21 to 40 ft
No. 6 : OFF
No. 7 : OFF
No. 3 : OFF
No. 4 : OFF
41 to 70 ft
No. 6 : ON
No. 7 : ON
No. 3 : ON
No. 4 : ON
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 tables below depending on the vent length.
3" venting
Vent length 240 Indoor (T-H3J-DV)
340 Indoor (T-H3S-DV)
540 Indoor (T-H3-DV)
(Upper bank of DIPswitches)
5 to 45 ft
(DEFAULT) No. 6 : ON
No. 7 : OFF
No. 3 : ON
No. 4 : OFF
46 to 70 ft
No. 6 : OFF
No. 7 : OFF
No. 3 : OFF
No. 4 : OFF
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
Set DIPswitches shown in the table below depending on the vent length.
<Singlepipewithroom-airintakeinstallaon>
<Two-pipe,direct-ventinstallaon>
Installaon
Installaon Manual
Refertop.16fordetails.
Refertop.17fordetails.

15 Page
-Exhaust vent (ABS, PVC, CPVC, or polypropylene vent)-
TheIndoormodelscanbeventedwithABS,PVC,CPVC,orpolypropylene(temperaturerateduptoat
least149°F).VentmaterialcertifiedtoULCS636standardsisrecommendedintheUSA.InCanada,
plastic venting must be certified to ULC S636 standards.
• Themaximumlengthofexhaustventpipingmustnotexceed70ft.(21.3m)for3”venting,which
dependsontheelevationwherethewaterheaterisinstalled,and100ft.(30.5m)for4”venting
(deducting 5 ft. (1.5 m) 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 5 ft. (1.5 m), support the vent run at 3 ft. (0.9 m) intervals
with overhead hangers.
Installaon
Installaon Manual
Item Material United States Canada
Exhaust pipe and
Fittings
Schedule40PVC ANSI/ASTM D1785
ULC S636 Certified
Materials Only
PVC-DWV ANSI/ASTM D2665
Schedule40CPVC ANSI/ASTM F441
Schedule40ABS-DWV ANSI/ASTM D2661
Polypropylene UL-1738
Pipe Cement/Primer
PVC ANSI/ASTM D2564
CPVC ANSI/ASTM F493
ABS ANSI/ASTM D2235
NOTE: Do NOT Use Cellular Foam Core Pipe
Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
3 in. (76 mm) 570 ft. (21.3 m)
4 in. (102 mm) 5100 ft. (30.5 m)
*For each elbow added, deduct 5 ft. (1.5 m) from max. vent length.
No. of Elbows
Max. Vertical or Horizontal (Total) Vent Length
3" venting 4" venting
Up to 3,000 ft Up to 6,000 ft Up to 10,100 ft Up to 10,100 ft
070 ft. (21.3 m) 40 ft. (12.2 m) 25 ft. (7.6 m) 100 ft. (30.5 m)
165 ft. (19.8 m) 35 ft. (10.7 m) 20 ft. (6.1 m) 95 ft. (29.0 m)
260 ft. (18.3 m) 30 ft. (19.1 m) 15 ft. (4.6 m) 90 ft. (27.4 m)
545 ft. (13.7 m) N/A N/A 75 ft. (22.9 m)
Excludes vent terminators, termination elbows, or rain caps.
For details on the vent connection, refer to p. 16 and p. 17.

16 Page
-Two-pipe, direct-vent illustraons-
For details of the optional items, refer to the Installation manual for each optional item.
<Howtoinstallintakeandexhaustventing(two-pipe,direct-vent)withtheindoormodels>
3"ventconnecon
From3"to4"ventconnecon
Installaon
Installaon Manual
3”coupling
Exhaust vent collar
(Female)
3”straightpipe
3”coupling
Intake vent collar
(Female)
3”straightpipe
1. Connect3"couplingsdirectlyonthe
exhaust and intake vent collar
of the water heater.
2. Connect3”straightpipestothe
couplings.
1. Connect3"x4"increasers
directly on the exhaust and intake
vent collar of the water heater.
2. Connect4”straightpipesto
the increasers.
4”straightpipe
3"x4" increaser
Exhaust vent collar
(Female)
Intake vent collar
(Female)
4”straightpipe
3"x4" increaser
HorizontalInstallaon VercalInstallaon
Roof
ashing
Roof
Fire stop
Wall
Connect between exhaust vent collar and piping.
Seetheinstruconsbelow.
Typicalinstallaonsusing PVC, ABS, or polypropylene vent

17 Page
-Single pipe with room-air intake illustraons-
For details of the optional items, refer to the Installation manual for each Optional item.
<Howtoinstallsingleventwiththeindoormodels>
3"ventconnecon
From3"to4"ventconnecon
Installaon
Installaon Manual
1. Connecta3"elbowdirectly
on the intake vent collar of the
water heater.
2. Connecta3"coupling directly
on the exhaust vent collar of the
water heater.
3. Connecta3”straightpipeto
the coupling.
TypicalinstallaonsusingPVC,ABS,orpolypropylenevent
1. Connecta3"elbowdirectly
on the intake vent collar of the
water heater.
2. Connecta3"x4"increaser directly
on the exhaust vent collar of the
water heater.
3. Connecta4”straightpipetothe
increaser.
3”coupling
3”straightpipe
Exhaust vent collar
(Female)
3” elbow with
bird screen
Intake vent collar
(Female)
4”straightpipe
3"x4" increaser
Exhaust vent collar
(Female)
3” elbow with
bird screen
Intake vent collar
(Female)
HorizontalInstallaon VercalInstallaon
Roof
Fire stop
Connect between exhaust vent collar and piping.
Seetheinstruconsbelow.
Roof
ashing
Elbow
Elbow
Wall

18 Page
-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 160 °F. For best results, a vent system
should be as short and straight as possible.
• TheIndoor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 NovaVent line. However, the following are also UL listed
manufacturers:ProTechSystemsInc.(FasNSeal),Metal-FabInc.,andHeat-FabInc.(Saf-TVent).
• Follow the vent pipe manufacturer’s instructions when installing the vent pipe.
• The maximum length of exhaust vent piping must not exceed 100 ft. (30.5 m) (deducting 5 ft. (1.5
m) for each elbow used in the venting system). Do not use more than 5 elbows.
• When the horizontal vent run exceeds 5 ft. (1.5 m), support the vent run at 3 ft. (0.9 m) intervals
with overhead hangers.
Diameter Max. No. ofElbows Max. Vertical and Horizontal (Total) Vent Length
4 in. (102 mm) 5100 ft. (30.5 m )
*For each elbow added, deduct 5 ft. (1.5 m) from max. vent length.
No. of Elbows Max. Vertical or Horizontal Vent Length
0100 ft. (30.5 m)
195 ft. (29.0 m)
290 ft. (27.4 m)
575 ft. (22.9 m)
Excludes vent terminators, termination elbows, or rain caps.
Installaon
Installaon Manual

19 Page
-Direct-vent and single vent Illustraons-
<Howtoinstallstainlesssteelventwiththeindoormodels>
• 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.
• Use4”CategoryIII/IVapprovedorSpecialBH,singleordoublewallstainlesssteelventpipe.
HorizontalInstallaon
Wall
Sidewall vent
terminaon
VercalInstallaon
Roof
Roofashing
Fire stop
Raincap
4"ventconneconfordirect-ventinstallaon
4”stainlesssteel
vent straight pipe
Exhaust vent collar
of the Indoor models
(Female)
Intake vent collar
(Female)
4”stainless
steel vent
straight pipe
Installaon
Installaon Manual
Typicalinstallaonsusingstainlesssteelvents
Exhaust vent collar
of the Indoor models
(Female)
4”stainlesssteel
vent straight pipe
Intake vent collar
(Female)
4” elbow with
bird screen
1. Connecta4"stainlesssteelvent
straight pipes directly on the
exhaust vent collar of the
water heater.
2. Connecta4"elbowdirectly
on the intake vent collar of the
water heater.
1. Connect4"stainlesssteelvent
straight pipes directly on the
exhaust/intake vent collar of the
water heater.
4"ventconneconforsingleventinstallaon
• The diagram above shows direct-vent installations. For single vent installation, connect a 4" elbow
directly on the intake vent collar instead of a straight pipe. See the instructions below for the detail.
• For details of the optional items, refer to the Installation manual for each Optional item.

20 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 ANSI Z223.1 / NFPA 54 or CAN/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