Takagi T-KJr2-IN / 110 User manual

65Q012-6
REV. 06(04-15)
Gas Tankless Water HeaterTM
Suitable for potable water heating and space-heating*
* Please refer to local codes for space-heating compliance.
FEATURING
 • ENDLESSHOTWATER
 • ON-DEMANDUSAGE
 • COMPACT,SPACESAVING
 • ENERGYCONSERVATION
 • COMPUTERIZEDSAFETY
 • NOPILOTLIGHT
 • EASY-LINKSYSTEM*
 • COMMERCIALGRADECOPPER*
  *(T-D2-IN/510modelonly)
Ifyouhaveanyquestions,
pleasecall1-888-479-8324
WARNING
Iftheinformationinthese
instructionsisnotfollowed
exactly,afireorexplosionmay
resultcausingpropertydamage,
personalinjuryordeath.
- 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
Models
T-KJr2-IN / 110
T-K4-IN / 310
T-D2-IN / 510
T-D2-IN/510
modelonly
ANSIZ21.10.3andCSA4.3

2
INSTALLATION MANUAL
SPECIFICATIONS ...............................3
INTRODUCTION ................................4
SAFETY GUIDELINES............................4
Safety Definitions ..............................4
General ......................................4
INSTALLATION .................................5
General ......................................5
Clearances ...................................7
Included Accessories ...........................7
Optional Items .................................7
High-altitude Installations .......................10
Venting Instructions............................10
General
Exhaust venting
Venting Illustrations
Vent Termination Clearances
Gas supply and gas pipe sizing ..................15
General
Gas Connections
Measuring Inlet Gas Pressure
Water Connections ............................15
Pressure Relief Valve
Electrical Connections..........................16
Remote Controller Connections ..................17
Pump Control Mode ...........................18
Easy-Link System .............................18
General
Easy-Link Connection Procedures
APPLICATIONS ................................20
Space-Heating Applications .....................20
Recirculation .................................21
Dual-purpose Hot Water Heating .................21
With T-D2-IN (510) Model Only
INITIAL OPERATION ............................22
OWNER'S GUIDE
OPERATING SAFETY ...........................23
NORMAL OPERATION ..........................25
General .....................................25
Temperature Settings ..........................25
Without Remote Controller
DIP switch Settings for Temperature
Flow........................................26
Freeze protection system .......................26
Maintenance and Service .......................27
Unit Draining and Filter Cleaning
Descaling the Unit
TROUBLESHOOTING ...........................29
General .....................................29
Error Codes..................................31
Single Unit Installations
Easy-Link System
Fault Analysis of Error Codes ....................32
COMPONENTS DIAGRAM .......................35
Case Assembly ...............................35
T-KJr2-IN / 110
T-K4-IN / 310 & T-D2-IN / 510
Burner Assembly ..............................36
T-KJr2-IN / 110
T-K4-IN / 310 & T-D2-IN / 510
Computer Board Assembly ......................38
T-KJr2-IN / 110 & T-K4-IN / 310
Water Way Assembly ..........................38
T-KJr2-IN / 110
Computer Board Assembly ......................38
T-D2-IN / 510
Water Way Assembly ..........................38
T-K4-IN / 310
Water Way Assembly ..........................39
T-D2-IN / 510
Water outlet section ...........................39
Water inlet section.............................39
PARTS LIST ...................................40
OUTPUT TEMPERATURE CHART .................42
T-KJr2-IN Models / 110
T-K4-IN Models / 310
T-D2-IN Models / 510
LIMITED WARRANTY ...........................43
Table of Contents

3
SPECIFICATIONS
Model T-KJr2-IN / 110 T-K4-IN / 310 T-D2-IN / 510
Natural Gas Input
(Operating Range)
Min.: 19,500 BTU/h
Max.: 140,000 BTU/h
Min.: 11,000 BTU/h
Max.: 190,000 BTU/h
Min.: 11,000 BTU/h
Max.: 199,000 BTU/h
Propane Input
(Operating Range)
Min.: 19,500 BTU/h
Max.: 140,000 BTU/h
Min.: 11,000 BTU/h
Max.: 190,000 BTU/h
Min.: 11,000 BTU/h
Max.: 199,000 BTU/h
Gas Connection 3/4” NPT
Water Connections 3/4” NPT
Water Pressure 15 - 150 psi*
Inlet
Pressure
Natural Gas Min. 5.0” W.C. Max. 10.5” W.C.
Propane Min. 8.0” W.C. Max. 14.0” W.C.
Manifold
Pressure**
Natural Gas 2.0” W.C. 2.0” W.C. 2.0” W.C.
Propane 2.5” W.C. 3.7” W.C. 3.7” W.C.
Weight 13 kg (28.7 lbs.) 18 kg (39.6 lbs.) 18 kg (39.6 lbs.)
Dimensions 520 mm (H) x 351 mm (W) x 170mm (D)
H 20 1/2" x W 13 3/4" x D 6 3/4"
520 mm (H) x 351 mm (W) x 216mm (D)
H 20 1/2” x W 13 3/4” x D 8 1/2”
Ignition Electric Ignition
Electric
Supply 120 VAC, 60 Hz
Consumption
Operation 73.1 W / 0.61 A 87.6 W / 0.73 A 89.8 W / 0.75 A
Standby 6.2 W / 0.05 A 6.2 W / 0.05 A 6.2 W / 0.05 A
Freeze-Protection 111 W / 0.93 A 111 W / 0.93 A 111 W / 0.93 A
* 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beforeinstallation.
• Themanufacturerreservestherighttodiscontinue,orchangeatanytime,specificationsordesignswithoutnoticeand
without incurring obligations.

4
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 or call an HVAC technician in your area.
• This equipment is an on-demand, tankless water heater
designed to efficiently supply endless hot water for your
needs.
• The T-KJr2-IN / 110, T-K4-IN / 310, & T-D2-IN / 510
models are to be installed indoors only (direct-vent
convertible).
• The principle behind tankless water heaters is simple:
Exhaust vent
collar
Burners
Cold Water
Inlet
Fan motor
Thermistor
Hot Water
Outlet
Heat
exchanger
Thermistor
Flow sensor
Computer
board
Gas Valves
Gas
Inlet
Flow adjustment
valve
* 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 igniter starts and the gas valve opens 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.
SAFETY GUIDELINES
Safety Denitions
DANGER
Indicates an imminently hazardous situation
which, if not avoided, will result in death or
serious injury.
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.
General
1. Follow all local codes, or in the absence of local codes,
follow the most recent edition of CSA B149.1 Natural
Gas and propane Installation Code.
2. Properly ground the unit in accordance with all local
codes or in the absence of local codes, with CSA C22.1
Canadian 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 pg. 6,7.)
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. 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.

5
DANGER
WARNING
• Water temperatures over 52 °C (125 °F)
can cause severe burns instantly or death
from scalding. The water temperature
is set at 50 °C (122 °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 pg. 16
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 heat exchanger will not be covered
under warranty if it is damaged due to
freezing. Refer to the section on the
Freeze Protection System on pg. 26 for
more information.
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 and 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 pg. 7 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 pg. 13, CSA B149.1.)
8. Particles from flour, aerosols, clothes dryers and other
airborne 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 environments. Sealed
combustion is recommended too.
9. For the T-KJr2-IN / 110, T-K4-IN / 310, & T-D2-IN / 510
models:
• These units may be converted to a direct-vent
(sealed combustion) appliance by installing a direct-
vent conversion kit (Part No. TK-TV10) which will
bring in all required combustible air from outside the
building. When installing the direct-vent conversion
kit, please follow all instructions included with the kit.
• If the water heater is used as a direct-vent appliance,
the unit requires a 76mm (3 in.) combustible air
supply pipe. The intake pipe must be sealed airtight.
Air supply pipe can be made of PVC, CPVC, ABS,
Polypropylene, corrugated stainless steel, Category
III / IV stainless steel or aluminum flex tube.
• Terminating the venting through a sidewall is
recommended for the direct-vent system.
• Running the exhaust vent and the intake pipe
parallel is recommended.
• Terminating the exhaust and intake on the same
wall/surface is recommended. Terminating in the
same pressure zone allows for pressure balancing,
which prevents nuisance shutdowns.

6
WARNING
• 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.
• If the above conditions cannot be
met, use the direct-vent conversion kit
TK-TV10.
• 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.
CAUTION
• The warranty will not cover damage
caused by water quality.
• Only potable water 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.
• The manufacturer recommends using
the direct-vent conversion kit when
the water heater is installed in a beauty
salon or anywhere there are airborne
contaminants. Some chemicals used
in a beauty salon may affect the flame
sensor. Water heater may not work
properly.
• 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.

7
WARNING FOR INSTALLATION
LOCATIONS
• 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 point-
ing toward any opening into a build-
ing. Do not locate your heater in a
pit or location where gas and water
can accumulate.
• Do not install this water heater vent
terminator within 914 mm (3 ft.) of
any air intake or building opening.
(Refer to p.13.)
• Do not install next to a dryer or
any source of airborne debris that
can be trapped inside the combus-
tion chamber, unless the system is
direct-vented.
Clearances
Model Top Bottom Front Back Sides
T-KJr2-IN /
110
305mm
(12 in.)
305mm
(12 in.)
102mm*
(4 in.)
25mm
(1 in.)
76mm
(3 in.)
T-K4-IN /
310
305mm
(12 in.)
305mm
(12 in.)
102mm*
(4 in.)
25mm
(1 in.)
76mm
(3 in.)
T-D2-IN /
510
305mm
(12 in.)
305mm
(12 in.)
102mm*
(4 in.)
25mm
(1 in.)
76mm
(3 in.)
*610 mm (24 inches) recommended for maintenance.
Maintain all clearances around the water
heater.
The diagram of clearance
Included Accessories
Check that these items below are included with the water
heater.
Items
Installation Manual & Owner’s
Guide Qty: 1
Communication Cable
(T-D2-IN / 510 models only) Qty: 1
Temperature
remote
controller
T-KJr2-IN /110
&T-K4-IN /310 TK-RE02 Qty: 1
T-D2-IN /510 TM-RE30 Qty: 1
Optional Items
Model T-KJr2-IN /
110
T-K4-IN /
310
T-D2-IN /
510
Universal
Appliance Adapter
(9008146005)
(2SVBFDPA04)
x x x
TK-TV10 x x x
TK-PC01 x x
TK-PCJr2 x
Sidewall vent
terminator(Hood)
/ Termination Box
& Wall thimble
x x x
Direct-vent concentric
termination kit
(2SVSHTCKIT43S
or
2SVSHTCKIT43)
x x x
TK-IV01-AB
(Isolation valve kit) x x x
914 mm
(3 ft.)
914 mm
(3 ft.)
914 mm
(3 ft.)
Vent
Terminal
V
WARNING
Prohibited
Top
Back
Side
Side
Front
Bottom

8
1. Temperature remote controller: TK-RE02 Please refer to the remote controller manual supplied with the remote.
The temperature remote controller has two functions. It allows the output
temperature from the water heater to be adjusted within the range of 37.5
°C to 75 °C (99 °F to 167 °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 37.5 °C (99 °F), 38 °C (100 °F), 39 °C (102 °F), 40 °C
(104 °F), 41 °C (106 °F), 42 °C (108 °F), 43 °C (110 °F), 44 °C (111 °F), 45 °C
(113 °F), 46 °C (115 °F), 47 °C (117 °F), 50 °C (122 °F), 55 °C (131 °F), 60 °C
(140 °F), 70 °C (158 °F), and 75 °C (167 °F). See the troubleshooting section
for information on possible error codes.
*The remote only provides the temperature display in Fahrenheit.
2. Temperature remote controller: TM-RE30 Please refer to the remote controller manual supplied with the remote.
The temperature remote controller has two functions. It allows the output
temperature from the water heater to be adjusted within the range of 37 °C
to 85 °C (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 37 °C (100 °F), 38 °C (100 °F), 39 °C (102 °F), 40 °C
(104 °F), 41 °C (106 °F), 42 °C (108 °F), 43 °C (110 °F), 44 °C (111 °F), 45 °C
(113 °F), 46 °C (115 °F), 47 °C (117 °F), 50 °C (122 °F), 55 °C (131 °F), 60 °C
(140 °F), 65 °C (149 °F), 70 °C (158 °F), 75 °C (167 °F), 80 °C (176 °F). See
the troubleshooting section for information on possible error codes.
3. 4 inches universal appliance adapter with back flow preventer and condensation drain: 9008146005 / 2SVBFDPA04
There are three functions available for this adaptor, which can be connected
with the water heater and Flex master 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.
Furthermore condensation drain from the combustion is discharged. Install
this adaptor in accordance with the installation instructions that are packaged
with the adaptor and any applicable codes.
4. Direct-vent conversion kit: TK-TV10
This kit can be used to convert the water heater from a standard vent system
to a direct-vent (or sealed combustion) system. Install this conversion kit in
accordance with the installation instructions and any applicable codes.
5 . Pipe Covers: TK-PC01 and TK-PCJr2
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.

9
6. Wall thimble and Sidewall vent terminations
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 Flexmaster brochure for details.) Install these
vent terminations in accordance with their installation instructions and any
applicable local code.
7. Direct-vent concentric termination kit
Used when terminating direct-vent (sealed combustion) systems, with indoor
models that require a 3 in. (76 mm) intake and a 4 in. (102 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.
This sidewall termination is available in two different sizes, to cover a wide
range of wall thicknesses. For different wall thicknesses, there are two ranges
of lengths available. (Refer to the Flexmaster brochure for details.)
8. Isolation valve kit: TK-IV01-AB
The kit uses Isolation Valves to isolate a unit for service. The Pressure Relief
Valve is to help protect the unit and release if the pressure in the tankless
water heater or hot water system exceeds 150 psi.
Covering wall thicknesses Part#
6.75 – 13.0 in. 2SVSHTCKIT43S
12.25 – 19.25 in. 2SVSHTCKIT43
Covering wall thicknesses Part#
Wall Thimble 4 - 7 in. 2SVSWTF04
Wall Thimble 5 - 10 in. 2SVSWTEF04
Termination Hood 2SVSHTX04
Termination Box 2SVSRTF04
Wall thimble Termination Hood
Termination Box

10
High-altitude Installations
Check the elevation where your water heater is installed.
Set DIP switches shown in the table below depending on
the altitude.
T-KJr2-IN / 110 & T-K4-IN / 310 Models
Altitude 0 to 2,000 ft
(DEFAULT)
2,001 to
4,000 ft
4,001 to
6,000 ft
Switch
No. 3 OFF ON OFF
Switch
No. 4 OFF OFF ON
ON
87654321
ON
87654321
ON
87654321
T-D2-IN / 510 Model (Left bank of DIP switches)
Altitude 0 to 2,000 ft
(DEFAULT)
2,001 to
4,000 ft
4,001 to
6,000 ft
Switch
No. 4 OFF ON OFF
Switch
No. 5 OFF OFF ON
ON
654321
ON
654321
ON
654321
• The dark squares indicate the direction the DIP switches
should be set to.
• The maximum certified or allowable installed altitude
is 6,000 ft.
T-KJr2-IN / 110 & T-K4-IN
/ 310 Computer board
DIP switches
T-D2-IN / 510
Computer board
DIP switches (Left bank)
WARNING
DO NOT adjust any DIP switches on the right
bank for the T-D2-IN / 510 model.
Venting Instructions
General
DANGER
• 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.
CAUTION
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.
The water heater 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 manufacturer recommends the Flexmaster line.
However, the following are also UL listed manufacturers:
ProTech Systems Inc. (FasNSeal), Metal-Fab Inc., and
Heat-Fab Inc. (Saf-T Vent).
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 water heater.
• The vent must be easily removable from the top of the
water heater for normal service and inspection of the
unit.
• 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, we
recommend that it be at least 305 mm (12 in.) above the
anticipated snow line, 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 the next few pages.

11
Exhaust venting
This is a Category III 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 177
°C (350 °F). For best results, a vent system should be as
short and straight as possible.
• This water heater is a Category III appliance and must
be vented accordingly with any 102 mm (4 in.) vent
approved for use with Category III or Special BH type
gas 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 approved
or Special BH vent pipe.)
• 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.
• The maximum length of exhaust vent piping must not
exceed 15.24 m (50 ft.) (deducting 1.5 m (5 ft.) for each
elbow used in the venting system). Do not use more
than 5 elbows.
Diameter Max. No. of
Elbows
Max. Vertical & Horizontal
(Total) Vent Length
102 mm (4 in.) 515.24 m (50 ft.)
* For each elbow added, deduct 1.5 m (5 ft.) from max.
vent length.
No. of
Elbows Max. Vertical or Horizontal Length
015.24 m (50 ft.)
113.7 m (45 ft.)
212.2 m (40 ft.)
310.7 m (35 ft.)
49.1 m (30 ft.)
57.6 m (25 ft.)
Excludes elbow termination, rain caps, or the 102 mm
(4 in.) Concentric Termination, Termination Hood and
Termination Box.
Venting Illustrations
For details of the optional items, refer to the Installation
manual for each Optional item.
Horizontal Installation Diagram:
Hanger
Wall
Sidewall vent
termination
Backow
preventer*
Vertical
condensation
drain**
Vertical Installation Diagram:
Rain cap
Storm collar
Fire stop
Vertical
condensation
drain**
Backflow
Preventer*
Roof
Hanger
Roof flashing

12
Horizontal Installation Diagram (with direct-venting)
Wall
Sidewall vent
terminations
Backow
preventer*
Vertical
condensation
drain**
See the picture below for
detailed connection instructions
to the Direct-vent conversion kit.
Vertical Installation Diagram (with direct-venting)
Fire Stop
Hanger
See the picture below for
detailed connection instructions
to the direct-vent conversion kit.
Roof
Rain cap
Backow
preventer*
Vertical
condensation
drain**
Roofashing
Roofashing
* Backflow preventer (Recommended for freezing weather
conditions: 2 °C (36 °F) and below).
** Vertical condensation drain must be installed in
accordance with local codes.
Horizontal Installation Diagram with Direct-Vent
Concentric Termination
Wall
Direct-vent concentric
termination
Installation Diagram of Direct-Vent Conversion Kit (TK-
TV10) with a water heater
Remove the air intake
cover plate to attach
the air intake port from
the Direct-vent
conversion kit. (TK-TV10)
Cover the louver of the water heater with the plate
provided in the Direct-vent conversion kit to complete the
conversion to sealed combustion.
Air intake cover plate
Storm collar

13
Vent Termination 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 * *
JClearance 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 Natural Gas and propane Installation Code, please use clearances in
accordance with local installation codes and the requirement of the gas supplier.

14
CAUTION
Please follow all local and national codes in
regards to proper termination clearances.
In the absence of such codes, the following
clearances can be used as guidelines. Local
codes supersede these guidelines.
For sidewall terminations
Inside
corner
Exhaust
terminations
610 mm
(2 ft.)
305 mm
(1 ft.)
305 mm
(1 ft.)
Inside
corner
610 mm
(2ft.)
915 mm
(3 ft.)
915 mm
(3 ft.)
Direct-vent
terminations
For multiple sidewall exhaust
terminations (e.g. Multi-
Unit systems), an exhaust
termination must be at least
305 mm (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 915 mm (3 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.)
3 ft.
3 ft.
3 ft.
Air supply inlet
Exhaust
termination
2 ft.
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.
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.
For rooftop terminations
A
A
A
Air
intake
Exhaust
termination
B
610 mm
(2 ft.)
AA
Exhaust
termination
Air
intake
A: In accordance with local codes
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.
B:
An exhaust termination shall extend not less than 915 mm
(3 ft.) above the highest point where it passes through the
roof of a building AND NOT less than 610 mm (2 ft.) higher
than any portion of a building within a horizontal distance of
3048 mm (10 ft.). (CSA B149.1 §8.14.4)

15
Gas supply and gas pipe sizing
General
WARNING
• 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 vice 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.
• The minimum and maximum inlet gas pressures are:
Gas type Inlet gas pressure
Natural Gas Min. 5.0” W.C. – Max. 10.5” W.C.
Propane Gas Min. 8.0” W.C. – Max. 14.0” W.C.
• Inlet gas pressures that fall outside the range of values
listed above may adversely affect the performance of the
water heater. 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 Connections
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 (see below) 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 1/2 psi (3.5 kPa).
• 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 1/2 psi (3.5kPa).
3. Always purge the gas line of any debris, inert gas* and/
or water before connecting to the gas inlet.
* Inert gas may be left in the line from pressure testing.
Note: Size the gas pipe appropriately to supply the
necessary volume of gas required for the water heater using
CSA B149.1 Natural Gas and propane Installation Code
or local codes. Otherwise, flow capabilities and output
temperatures may be limited. The installation shall comply
with CSA B149.1 Natural Gas and propane Installation
Code.
Measuring Inlet Gas Pressure
1. Turn off all electric power to the water
heater if service is to be performed.
2. Turn the manual gas valve located on
the outside of the unit clockwise to the off
position.
The water heater cannot perform properly without sufficient
inlet gas pressure. Below are instructions on how to check
the inlet gas pressure. THIS IS ONLY TO BE DONE BY A
LICENSED PROFESSIONAL.
1. Shut off the manual gas valve on the supply gas line.
2. Remove the screw for the pressure port located on the
gas inlet of the water heater shown in the diagram below.
3. Connect the manometer to the pressure port.
4. Re-open the manual gas valve. Check to see that there
are no gas leaks. Take a reading of the gas pressure.
Open some of the fixtures that use the highest flow rate
to turn on the water heater.
5. Check the inlet gas pressure. Take another reading.
When the water heater is on maximum burn, the manom-
eter should read from 5.0” to 10.5” W.C. for Natural gas
or from 8.0” to 14.0” W.C. for Propane. Verify drop meets
code.
Pressure
port
Water Connections
CAUTION
• Do not use this water heater if any
part has been submersed under water.
Immediately call a licensed professional
to inspect the water heater to replace any
damaged parts.
• Do not reverse the hot outlet and cold
inlet connections to the water heater.
This will not properly activate the water
heater.
All pipes, pipe fittings, valves and other components,
including soldering materials, must be suitable for potable
water systems.
1. A manual shutoff valve must be installed on the cold
water inlet to the water heater between the main water
supply line and the water heater.

16
2. In addition, a manual shutoff valve is also recommended
on the hot water outlet of the unit. If the water heater
is installed within, or subjected to, a closed loop water
system, a thermal expansion tank must be installed on
the return side. We recommend isolation valve sets
with hose bibs for serviceability such as flushing. See
maintenance section.
3. Before installing the water heater, flush the water line
to remove all debris, and after installation is complete,
purge the air from the line. Failure to do so may cause
damage to the heater.
4. There is a wire mesh filter within the cold inlet to trap
debris from entering your heater. This will need to be
cleaned periodically to maintain optimum flow.
Hot outlet Cold inlet Gas inlet
As close as
possible
Pressure
Relief Valve
Pressure Relief Valve
The water heater has a high-temperature shutoff switch built
in as a standard safety feature (called a Hi-Limit switch)
therefore a “pressure only” relief valve is required.
• This unit does not come with an approved pressure relief
valve.
• An approved pressure relief valve must be installed on
the hot water outlet.
• The pressure relief valve must conform to CAN 1-4.4 and
installation must follow local codes.
• The discharge capacity must be at least 140,000 BTU/h
for the T-KJr2-IN / 110, 190,000 BTU/h for the T-K4-IN /
310, and 199,000 BTU/h for the T-D2-IN / 510.
• The pressure relief valve needs to be rated for a
maximum of 150 psi.
• The discharge piping for the pressure relief valve must be
directed so that the hot water cannot splash on anyone or
on nearby equipment. Follow local codes.
• Attach the discharge tube to the pressure relief valve and
run the end of the tube to within 152 mm (6 in.) from the
floor. This discharge tube must allow free and complete
drainage without any restrictions.
• If the pressure relief valve installed on the water heater
discharges periodically, this may be due to a defective
thermal expansion tank or defective pressure relief valve
or it could be signs of internal scale build up.
• The pressure relief valve must be manually operated
periodically to check for correct operation.
• No valve may be placed between the relief valve and the
water heater.
Electrical Connections
WARNING
Follow the electrical code requirements of
the local authority having jurisdiction. In
the absence of such requirements, follow
the latest edition of CSA C22.1 Canadian
Electrical Code, Part 1.
CAUTION
When servicing or replacing parts within
the water heater, label all wires prior to
disconnection to facilitate an easy and error-
free re-connection. Wiring errors can cause
improper and dangerous operation. Verify
proper operation after servicing.
1. The water heater requires 120 VAC, 60 Hz electrical
power supply that is properly grounded.
2. The use of a surge protector is recommended in order to
protect the unit from power surges.

17
Remote Controller Connections
To connect the remote controller to the water heater:
1. Disconnect power supply from the water heater.
2. Take off the water heater’s front cover.
3. Wires used for the remote controller connection must be:
• Minimum 20 gauge wire (No polarity)
• T-KJr2-IN / 110 & T-K4-IN / 310 models (TK-RE02)
Maximum 45 m (150 ft.) long
T-D2-IN / 510 model (TM-RE30)
Maximum 122 m (400 ft.) long
* For detailed connection to the remote controller, refer
to the instructions that are packaged with the remote
controller.
4. Pick location of install for the remote controller.
5. Cut enough two pair wire.
6. Crimp on supplied fork connectors.
7. Locate the remote controller terminals, pictured below
(located around the lower right-hand side of the computer
board).
8. Open the plastic cover of the remote controller, and then
attach the two fork terminals to connector base of the
backside of the remote controller with two screws. Make
sure the terminals are firmly fixed.
9. Pull the remote’s wires through the hole at the bottom of
the water heater’s casing.
10.Properly attach the remote’s wires to the remote controller
terminals on the computer board. (No polarity)
* Do NOT jump or short-circuit the wires, or the
computer board will be damaged.
11.Replace the plastic computer board cover and then
replace the front cover securely.
NOTE*: If the T-D2-IN / 510 model is used in an Easy-Link
System, the remote MUST be connected to the Parent unit.
Only one remote controller is needed in an Easy-Link System.
Connect to
these terminals
TK-RE02
Front of
remote
controller
T-KJr2-IN / 110 & T-K4-IN / 310 models
Back of
remote
Connect to these
terminals
T-D2-IN /510 model TM-RE30
Front of
remote
controller
Back of
remote
Connect to these
terminals
Connect to
these terminals

18
Pump Control Mode
(Available on the T-D2-IN / 510 model only)
The T-D2-IN / 510 water heaters can be used to control a
recirculation pump. Proper pump control helps to preserve
the life of the system and saves energy as well.
The water heater pump control port is a “normally-open
dry contact”, and therefore needs additional components
to properly control a recirculation pump. To control a
recirculation pump, connect the pump to the “Pump
connector” in the water heater as shown in the diagram
below. (In an Easy-Link System, connect the pump ONLY
to the “PARENT” unit.) The pump is to be connected using
suitable relays shown in the diagram below.
Please make sure the relays are properly rated for the
recirculation pump.
Using the water heater’s internal thermistors as a
temperature control, the recirculation pump will only turn on
when recirculation is needed.
CAUTION
In an Easy-Link System, the pump must
be connected to the “Pump connector”
in the “PARENT” unit only. If the pump is
connected to any of the “CHILD” units, the
pump will not work.
Recirculation
pump
Connect to this
“Pump connector”
Power supply
for relay
Power supply
for pump
120 VAC
220 VAC etc
120 VAC
220 VAC etc
for relay
Thermal relay for
additional safety
These components
are NOT included
with the water
heater and are
external to the
unit. They must be
acquired separately.
Easy-Link System
(Available on the T-D2-IN / 510 model only)
General
The T-D2-IN / 510 water heaters can be connected with
other heaters of the same model with communication cables
to work as a multiple-unit manifold system.
• The Easy-Link System allows up to 4 units to manifold
together.
• A communication cable (gray color) comes with each
T-D2-IN / 510 model.
You can manifold from 2 to 4 units without the need for a
Multi-Unit Controller. A 4-unit system has full automatic
modulation between 11,000 BTU/h and 796,000 BTU/h.
Gas In
Cold In
Hot Out
CAUTION
• The Easy-Link System is limited up to 4
units. If you connect more than 4 units,
only the first 4 units will work as a part
of the Easy-Link System. The other
additional units will not work correctly and
fluctuating water temperatures or no hot
water may be a result.
• All units within an Easy-Link System
must be of the same exact model.
Easy -Link System is backward com-
patible with the T-K3 and T-K3 Pro,
no other models cannot be combined
together to form an Easy-Link System.
• Only change DIP switch settings with
power off.
Easy-Link Connection Procedures
1. Make sure the power to the water heaters are off.
2. Verify the set temperatures of all units within the
system. Every single water heater must be set to the
same set temperature. See *Note on the next page.
3. Select one unit to be the “PARENT” unit with power off.
4. “PARENT” unit:
Locate the two banks of DIP switches at the right of the
7-Seg LED on the computer board of the unit that you
select to be the “PARENT” unit. Change DIP switch
No. 1 on the right bank of DIP switches to the ON
position. See the computer board diagram as shown
in the next page. Do not change any DIP switches on
any of the “CHILD” units.
5. Between the “PARENT” and the “CHILD-1” units:
Connect the “PARENT” connector of the “PARENT”
unit to the “1” connector of the “CHILD-1” unit.
6. Between the “CHILD-1” and the “CHILD-2” units:
Connect the “2” connector of the “CHILD-1” unit to the
“1” connector of the “CHILD-2” unit.
7. Between the “CHILD-2” and the “CHILD-3” units:
Connect the “2” connector of the “CHILD-2” unit to the
“1” connector of the “CHILD-3” unit.

19
8. Make sure the 7-Seg LED of all the units’ computer boards
display the unit #. The numbering system automatically
allocates the unit # to each water heater in the Easy-Link
System, in accordance with the table below.
Parent unit Unit #: 1
Child units Unit #: 2, 3 or 4
(A) T-D2-IN / 510 Computer board
Easy-Link System
“Online” LED
Left bank of
DIP switches
7-Seg. LED
Right bank of
DIP switches
Easy-Link connectors
are next to the
computer board.
To change the DIP switch settings for the Easy-Link System,
locate the bank of DIP switches at the right of the 7-Seg
LED. Do not adjust the left bank of DIP switches.
(B) Basic diagram of connections between the Easy-Link
System units.
Communication
cable
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
PARENT
unit
CHILD-1
unit
CHILD-2
unit
CHILD-3
unit
CAUTION
The dark squares indicate the direction the
DIP switches should be set to.
*Note:
• A remote controller is not required for the Easy-Link
System.
• If running the Easy-Link System without a remote
controller, please make sure the temperature settings on
ALL the units are set to the same settings. Otherwise,
the units will not operate properly.
• If a remote controller is used, the temperature on all the
units in the system will automatically be set to the same
temperature that is set on the remote.
(C) Examples of incorrect settings and/or connections
CASE 1:
• Unless you change DIP switch No. 1 of the “PARENT”
unit to the “ON” position, the system will not work as an
Easy-Link System. The units will operate as individual
units.
Communication
cable
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
PARENT
unit
CHILD-1
unit
Wrong
setting
Prohibited
Wrong DIP switch setting on the “PARENT”
unit
CASE 2:
• If you connect the “1" (or "2") connector of the “PARENT”
unit to the “PARENT" (or "1") connector of the “CHILD-1”
unit, the system will not work as an Easy-Link System.
The units will operate as individual units.
Communication
cable
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
PARENT
unit
CHILD-1
unit
Wrong
connection
Wrong
connection
OR
Communication
cable
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
PARENT
unit
CHILD-1
unit
Wrong
connection
Wrong
connection
Prohibited
Wrong connections between the “PARENT”
unit and the “CHILD-1” unit

20
CASE 3:
• If you connect the “PARENT” connector of the “CHILD-
1” unit to the “1” connector of the “CHILD-2” unit, the
“CHILD-2” unit will operate as an individual unit, and will
not be part of the Easy-Link System.
Communication
cable
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
PARENT
unit
CHILD-1
unit
Wrong
connection
CHILD-2
unit
Prohibited
Wrong connections between the “CHILD-1”
unit and the “CHILD-2” unit
WARNING
Connecting two “PARENT” connectors
together from two separate units may
damage the computer board. The
communication cable has a female end
and a male end so it’s impossible to have
a PARENT-to-PARENT connection with the
communication cable. Do not splice or
modify connectors.
CASE 4:
• If a remote controller is used, it has to be connected to
the “PARENT” unit. If the remote controller is connected
to a “CHILD” unit, it will only control that particular
individual “CHILD” unit and will not control the Easy-Link
System as a whole.
Communication
cable
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
Connectors
Right bank of
Dipswitches
OFF
ON
1
23456
PARENT
1
2
PARENT
unit
CHILD-1
unit
Wrong
connection
Remote
controller
Prohibited
Remote controller connected to incorrect unit
APPLICATIONS
Space-Heating Applications
WARNING
• In order to purge air in water pipes
within a closed-loop system, an air vent
and air separator should be installed
in the system. Required circulation
flow rates are labeled next to each
application diagram. These flow rate
requirements must be followed.
• Toxic chemicals used in boiler treatments
such as alcohol, glycerol and glycol
groups must not be introduced into the
system if the system incorporates an
open-loop potable water system.
• The water heater can be used to supply
potable water and space heating and shall
not be connected to any heating system or
component(s) previously used with non-
potable water where any chemicals were
added to the water heating appliances.
• Water heaters for combination water/
space heating cannot be used in space
heating applications only.
• When the system requires water for
space heating at temperatures higher
than required for other uses, a means
such as a mixing valve shall be installed
to temper the water for those other uses
in order to reduce scald hazard potential.
• Water temperature over 52 °C (125 °F)
can cause severe burns instantly or death
from scalding.