Takagi 110 Indoor User manual

On-Demand Water Heater
Installation Manual and Owner’s Guide
FEATURING
• ENDLESSHOTWATER
• ON-DEMANDUSAGE
• COMPACT,SPACESAVING
• ENERGYCONSERVATION
• COMPUTERIZEDSAFETY
• NOPILOTLIGHT
• EASY-LINKSYSTEM
510 model only
• ComplieswithnaturalgasLow
NOxemissionsof40ng/Jor
55ppm.
Gas Tankless Water HeaterTM
Suitable for combination potable water heating
and space heating. Please refer to local codes for
space-heating compliance.
Ifyouhaveanyquestions,
pleasecallorwriteto:
IntheUnitedStates
500TennesseeWaltzParkway
AshlandCity,TN37015
TollFree:1-877-737-2840
InCanada
599HillStreetWest
Fergus,ONN1M2X1
1-888-479-8324
- 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.
WARNING
If the information in these
instructions is not followed
exactly,afireorexplosionmay
resultcausingpropertydamage,
personalinjuryordeath.
ANSIZ21.10.3・CSA4.3 510
modelonly
R
DR
Keep this manual near the water heater for future reference whenever maintenance, adjustment, or
service is required.
Models
• 110Indoor
• 310Indoor
• 510Indoor
• 110Outdoor
(USAOnly)
• 310Outdoor
(USAOnly)
• 510Outdoor
(USAOnly)

2Page
Contents
CONTENTS
Installation Manual
SPECIFICATIONS .............................................4
INTRODUCTION ..........................................5
SAFETY GUIDELINES.....................................6
SAFETY DEFINITION....................................6
GENERAL......................................................6
INSTALLATION ................................................7
GENERAL......................................................7
CLEARANCES ...............................................9
INCLUDED ACCESSORIES............................9
OPTIONAL ITEMS........................................9
WARNING FOR INSTALLATIONS...............11
 .............12
VENTING INSTRUCTIONS.........................13
General .....................................................13
Combustion Air Supply .............................15
Exhaust venting ........................................19
Venting illustrations..................................20
Vent termination clearances ....................21
Clearances for sidewall terminations .......22
Clearances for rooftop terminations ........23
GAS SUPPLY AND GAS PIPE SIZING.........24
General .....................................................24
Gas connections .......................................24
Natural gas supply piping .........................25
Propane (LP) supply piping.......................25
WATER CONNECTIONS .............................26
Pressure relief valve .................................26
ELECTRICAL CONNECTIONS.....................27
TEMPERATURE REMOTE CONTROLLER .....27
Installation................................................27
PUMP CONTROL CONNECTIONS .................28
 .........................................29
General .....................................................29
Easy link connection procedures ..............29
APPLICATIONS..............................................31
SPACE HEATING APPLICATIONS...............31
RECIRCULATION ........................................31
......32
INITIAL OPERATION .....................................33
Owner's Guide
OPERATING SAFETY .....................................35
NORMAL OPERATION ..................................37
GENERAL....................................................37
TEMPERATURE SETTINGS ........................37
OTHER FEATURES OF THE REMOTE
CONTROLLERS...........................................39
TEMPERATURE SETTINGS ON THE PCB ........41
FLOW .......................................................... 41
FREEZE PROTECTION SYSTEM ................. 42
MAINTENANCE AND SERVICE ................. 42
Measuring inlet gas pressure ...................43
UNIT DRAINING AND FILTER CLEANING ....... 43
TROUBLESHOOTING...................................44
GENERAL....................................................44
ERROR CODES ...........................................46
General .....................................................46
Single unit installations.............................46
Easy-Link System for 510 model only .......46
Fault analysis of error codes.....................47
COMPONENTS DIAGRAM ............................49
PARTS LIST....................................................53
OUTPUT TEMPERATURE CHART ..................56

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 installation

If you need an additional manual, contact the manufacturer or your
local distributor. When you call, please tell us the product name and
the serial number of your unit written on the rating plate of the water
heater.

4Page
Model 110
Indoor
110
Outdoor
310
Indoor
310
Outdoor
510
Indoor
510
Outdoor
Natural Gas Input
(Operating Range) BTU/h Min.: 19,500 Max.: 140,000
Min.: 11,000
Max.: 190,000
Min.: 11,000
Max.: 199,000
Propane Gas Input
(Operating Range) BTU/h Min.: 19,500 Max.: 140,000
Min.: 11,000
Max.: 190,000
Min.: 11,000
Max.: 199,000
Gas Connection 3/4" NPT
Water Connections 3/4" NPT
Water Pressure* psi
(Mpa) 15 - 150* (0.1 - 1.0)
Natural gas
Inlet Pressure
" W.C.
(kPa)
Min. 4.0 (1.00)
Max. 10.5 (2.61)
Propane gas
Inlet Pressure
" W.C.
(kPa)
Min. 8.0 (1.99)
Max. 14.0 (3.48)
Weight lbs. (kg) 33 (15.0) 38 (17.2) 39 (17.7)
Dimensions inch H 20.5 x W 13.8 x D 6.7 H 20.5 x W 13.8 x D 8.5
mm 520 (H) x 351 (W) x 170 (D) 520 (H) x 351 (W) x 216 (D)
Ignition Electric Ignition
Electric
Supply VAC / Hz 120 / 60
Consumption
Operation W / A 73.1 / 0.61 87.6 / 0.73 89.8 / 0.75
Standby W / A 6.2 / 0.05 6.2 / 0.05 6.2 / 0.05
Freeze-
Protection W / A 111 / 0.93 111 / 0.93 111 / 0.93
Water heater category** Category
III N/A Category III N/A Category III N/A
SPECIFICATIONS
Specicaons
Installaon Manual
*40 psi or above is recommended for maximum flow.
**Water heater Category — water heaters of other than direct vent type, for outdoor installation, are divided into four
categories based on static pressure produced in the vent and flue loss.
Category I - a water heater that operates with a non-positive vent static pressure and with a vent gas temperature
that avoids excessive condensate production in the vent.
Category II - a water heater that operates with a non-positive vent static pressure and with a vent gas temperature
that may cause excessive condensate production in the vent.
Category III - a water heater that operates with a positive vent static pressure and with a vent gas temperature that
avoids excessive condensate production in the vent.
Category IV - a water heater that operates with a positive vent static pressure and with a vent gas temperature that
may cause excessive condensate production in the vent.
NOTE:
 
 The manufacturer reserves the right to discontinue, or change at any time, specifications or designs
without notice and without incurring obligation.

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/front 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.
 The 110 Indoor, 310 Indoor, and 510 Indoor models are only to be installed indoors (direct-
vent convertible). The 110 Outdoor, 310 Outdoor, and 510 Outdoor models are only to be
installed outdoors.
 The principle behind tankless water heaters is simple:
Burners

Exhaust vent
Heat exchanger
Gas valves
Fan motor
Flow adjustment valve
Computer board
Thermistor
Cold water inlet
Hot water outlet Gas inlet
Thermistor
Burners
Flow sensor
Igniter
1
2
3
4
54
6
7
7
7
8
Intake vent
*This diagram illustrates tankless water heater design concepts only and does not accurately represent
the water heater’s physical description.
1. A hot water fixture is turned on.
2. Water flows through the heater.
3. The water flow sensor detects the water flow.
4. The computer initiates the fan motor and gas valve to let gas flow through the heater 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 is heated as it flows through the heat exchanger.
7. Using thermistors to measure temperatures throughout the water heater, the computer modulates
the gas and water valves to ensure proper output water temperature and hot water outflows.
8. When the fixture is turned off, the unit shuts down.
Introducon
Installaon Manual

6Page
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the current edition of the National Fuel
Gas Code: ANSI Z223.1/NFPA 54 in the USA or B149.1, Natural Gas and 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 current edition of the National Electrical Code: 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 combustion 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 fixtures and turn off the gas. Then call a trained
technician, the gas company, or the manufacturer.
SAFETY GUIDELINES
SAFETY DEFINITION
WARNING
 Water temperatures over 125 °F (52 °C) can cause severe burns instantly or death
from scalding. The water temperature is set at 122 °F (50 °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 qualified installer or service agency to replace a flooded
water heater. Do not attempt to repair the unit. It must be replaced.
 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 "Freeze Protection System" on p. 42 for more information.
 Failure to observe these warnings could result in severe personal injury or death.
Safety Guidelines
Installaon Manual
WARNING
Indicates an imminently hazardous situation which, if not avoided, could result in death or seri-
ous injury.
CAUTION
Indicates an imminently hazardous situation which, if not avoided, could result in minor or
moderate injury.
Indicates an imminently hazardous situation which, if not avoided, will result in death or serious
injury.
DANGER
Indicates information considered important but not hazard related.
NOTICE

7Page
INSTALLATION
GENERAL
1. Follow all local codes, or in the absence of local codes, follow the current edition of the National
Fuel Gas Code: ANSI Z223.1/NFPA 54 in the USA or 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. Electrical service to the water heater requires a means of disconnection. This will allow power to
the water heater to be shut off 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
from any doorway or opening to prevent exhaust from entering a building. (Refer to pp. 21 and 22.)
Check local code requirements to prior to installation.
8. Carefully plan the installation location of the heater and vent terminations. Contaminants such as
aerosols, lint, and fine powders (including flour) can clog the air intake and reduce the operation
of the fan. This, in turn, can cause improper combustion and reduce the life of the water heater.
Regularly ensure that the area around the water heater, vent termination, and air intake is free of
dust, debris, and other contaminants. In environments with a high level of contaminants (laundry
facilities, hair salons, pet salons, chemical plants, commercial kitchens, etc.), direct venting is
required.
9. If you will be installing the water heater in a contaminated area with a high level of dust, sand, flour,
aerosols or other contaminants/chemicals, they can become airborne and enter and build up within
the fan and burner causing damage to the water heater.
10. 110 Indoor, 310 Indoor, and 510 Indoor models:
 These units may be converted to a direct-vent (sealed combustion) appliance by installing a
 
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 3 in. (76 mm)
combustible air supply pipe. The intake pipe must be sealed airtight. Air supply pipe can be
made of ABS, PVC (solid core), CPVC (solid core), Polypropylene, corrugated stainless steel, or
Category lll / IV stainless steel.
 Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in
non-metallic venting systems is prohibited. Covering non-metallic vent pipe and fittings with
thermal insulation is prohibited.
 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.
11. 110 Outdoor, 310 Outdoor, and 510 Outdoor models are only to be installed outdoors and only in
areas with mild, temperate climates.
Installaon
Installaon Manual

8Page
Installaon
Installaon Manual
 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.
 The manufacturer recommends direct venting using the direct-vent kit 100112184
(TK-TV-10) when the water heater is installed in beauty salons, dry cleaners or any
other locations in which such chemicals are present in the air. Some chemicals used
in beauty salons or dry cleaners may affect the flame sensor. In such cases, the 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.
NOTICE
 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.
 Do not install the unit where water, debris, or flammable vapors may get into the flue
terminal or the air intake line.
 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.
Failure to do so could lead to carbon monoxide poisoning or death.
 
sensor, the water heater will shut down on an error code.
 If the above conditions cannot be met, use the direct-vent conversion kit Part No.

 Place the unit where it will allow easy access for service and maintenance.
 A drain pan, or other means of protection against water damage, is
recommended to be installed under the water heater in case of leaks.
 The water heater must be securely mounted to a wall or other suitable structure.
 Failure to observe these warnings could result in severe personal injury, death,
and/or property damage.
WARNING

9Page
Top
Back

Side
Side
Front
CLEARANCES
Model Top Bottom Front Back Sides
110 Indoor
310 Indoor
510 Indoor
12 in.
(305 mm)
12 in.
(305 mm)
4 in.*
(102 mm)
1 in.
(25 mm)
3 in.
(76 mm)
110 Outdoor
310 Outdoor
510 Outdoor
36 in.
(914 mm)
12 in.
(305 mm)
24 in.
(610 mm)
1 in.
(25 mm)
3 in.
(76 mm)
OPTIONAL ITEMS
No. Model 110
Indoor
110
Outdoor
310
Indoor
310
Outdoor
510
Indoor
510
Outdoor
1100112416
(4” Backflow preventer and F-F adaptor) ✓ ✓ ✓
2100112184
(Direct-vent conversion kit) ✓ ✓ ✓
3
100112187(Pipe cover) ✓✓✓✓
100112188 (Pipe cover) ✓ ✓
4
100266729 (Recess box) ✓✓✓
100266730 (Recess box) ✓✓✓
5100112424/100112425
(Termination & Wall thimble kit) ✓ ✓ ✓
6100112550/100112551
(Direct-vent concentric Termination) ✓ ✓ ✓
Installaon
Installaon Manual
Model 110 Indoor 110 Outdoor 310 Indoor 310 Outdoor 510 Indoor 510 Outdoor
100112183
 ✓ ✓ ✓ ✓
100112155
(TM-RE30) ✓ ✓
*24 inches (610 mm) recommended for maintenance
Maintain all clearances around the water
heater. Failure to do so could create a fire
hazard, potentially leading to death, serious
injury, and/or property damage.
WARNING
INCLUDED ACCESSORIES
1. Installation manual
and Owner’s guide
2. Temperature
remote controller
3. Communication cable
510 model only
Qty: 1
or
100112183

100112155
(TM-RE30)
Check that these items below are included with the water heater.
Qty: 1
Qty: 1
100076516

10 Page
2. Direct-vent conversion kit: 100112184
(TK-TV10)
This kit can be used
to convert the water
heater from a single
vent system to a
direct-vent (double vent) (or sealed combustion)
system with a 3 in. (76 mm) intake. Install this
conversion kit in accordance with the installation
instructions and any applicable codes.
Thepipecoverprotects
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.
4. Recess box: 100266729 (No flange/retrofit application)
100266730 (With flange/new construction
application)
1. 4” Backflow preventer and F-F adaptor:
100112416
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 kit: 100112424/100112425
Installaon
Installaon Manual
Covering wall thicknesses Part#
Terminator Hood 100112419
Wall Thimble 4 - 7 in. 100112732
Wall Thimble 5 - 10 in. 100112733
Termination + Thimble 4 - 7 in. 100112424
Termination + Thimble 5 - 10 in. 100112425
3. Pipe cover: 100112187 (TK-PC01)
100112188 (TK-PCJr2)
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.
Wall Thimble
Terminator Hood
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.
(Refer to the venting manufacturer's specifications for details.)
Covering wall thicknesses Part#
5.0 – 10.0 in. (127 - 254 mm) 100112550
12.0 – 18.0 in. (305 - 457 mm) 100112551
6. Direct-vent concentric termination:
It allows for “clean” installations. The water heater fits inside the
recess box, which hides and protects the whole water heater and
plumbing. The recess box will fit between most wall studs.
100266729
Outdoor recess box
for retrofic applications-
no flange
100266730
Outdoor recess box
for new construction
applications-with flange

11 Page
WARNING FOR INSTALLATIONS
FOR YOUR SAFETY, READ BEFORE INSTALLATION:
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 (915 mm) from its top
or eaves. The area under an overhang must be
open to three sides. (Outdoor models only)
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.
Prohibited
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.
Prohibited
3 ft
(915 mm)
Installaon
Installaon Manual
Water heater vent terminator must be at least 2
ft (610 mm) away from an inside corner for both
outdoor installation and direct-vent installation.
Inside
Corner
2 ft
(610 mm)
USA: 1  (30 cm) min.
Canada: 3  (91 cm) min.
USA: 1  (30 cm) min.
Canada: 3  (91 cm) min.
USA: 1  (30 cm) min.
Canada: 3  (91 cm) min.
USA: 12 in. (30 cm) above grade and
above ancipated snow level
Canada: 12 in. (30 cm) above grade
Ancipated snow level
Ensure that you meet the minimum clearances
shown below for a direct vent termination:

12 Page
Installaon
Installaon Manual
NOTE: The dark squares indicate the correct DIP switch positions.
110 and 310 models
Altitude
0 to 2,000 ft
(0 to 610 m)
DEFAULT
2,000 to 4,000 ft
(611 to 1,219 m)
4,000 to 6,000 ft
(1,220 to 1,829 m)
Switch No. 3 OFF ON OFF
Switch No. 4 OFF OFF ON
ON
87654321
ON
87654321
ON
87654321
510 model (Left bank of DIP switches)
Altitude
0 to 2,000 ft
(0 to 610 m)
DEFAULT
2,000 to 4,000 ft
(611 to 1,219 m)
4,000 to 6,000 ft
(1,220 to 1,829 m)
Switch No. 4 OFF ON OFF
Switch No. 5 OFF OFF ON
ON
654321
ON
654321
ON
654321
Installation altitude
The maximum certified or allowable installed altitude is 6,000 ft (1,829 m) for indoor and out-
door models.
HIGH-ALTITUDE INSTALLATIONS
Check the altitude where your water heater is installed. Set DIP switches shown in the table below. The
DIP switch settings depend on the altitude.
WARNING
• Adjust the appropriate DIP switches according to model and elevation as
shown below. DO NOT adjust the other DIP switches.
• Turn off the power supply to the water heater before changing the DIP
switch settings.
• Failure to observe these warnings could lead to carbon monoxide poisoning
or death.
110 and 310 models
Computer board
DIP switches
510 model
Computer board


13 Page
Installaon
Installaon Manual
VENTING INSTRUCTIONS
Indoor models
-General-
WARNING
 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.
 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 “Venting of Equipment" in the current edition of the
National Fuel Gas Code: ANSI Z223.1/NFPA 54 in the United States and/or Section 8 of the current B149.1
Natural Gas, propane installation code in Canada, as well as applicable local building codes.
The manufacturer recommends NovaVENT™ or Z-Vent® category III, single wall, stainless steel venting.
See "Approved Category III, Single Wall, Stainless Steel Venting Suppliers and Part Numbers" on p. 14.
General rules for air intake:
The water heater can obtain its combustion air from the space that it is installed in or it can be direct
vented using the direct vent conversion kit 100112184(TK-TV10).
 Ensure that the installation location has sufficient, clean combustion air. If unsure, direct vent the
heater or refer to the Combustion Air Supply section below.
Direct venting installation:
 The air intake can use 3" PVC (solid core), CPVC (solid core), ABS, or category III vent.
 Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in non-
metallic venting systems is prohibited. Covering non-metallic vent pipe and fittings with thermal
insulation is prohibited.
 The maximum length of intake air piping must not exceed 50 ft (15.2 m). Deduct 5 ft (1.5 m) for
each 90° elbow or 2.5 ft (0.76 m) for each 45° elbow used in the venting system. Two 45° elbows
when connected together are equivalent to one 90° elbow. Refer to the tables on p. 19.
 When the horizontal air intake exceeds more then 5 ft (1.5 m), support the pipe every 3 ft (0.9 m)
with pipe hangers.
 Vertical air intake pipe must be supported with pipe hangers. Ensure that the weight of the pipe
is not carried by the water heater.
Combustion air from the room:
 Indoor models can obtain its combustion air from the space through an inner intake vent.
General rules for venting water heaters:
 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 and vent system.
 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.

14 Page
 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 must be at least 12 in. (305 mm) above grade and anticipated snow
line, but the installer may determine if it should be higher depending on the job site condition
and applicable codes.
 A proper sidewall termination is required when the water heater is vented through a sidewall.
 Regarding the clearances from the exhaust termination to the air inlet or opening, refer to
pp. 21 to 23.
Approved Category III, Single Wall, Stainless Steel Venting Suppliers and Part Numbers
WARNING! Do not mix parts or fittings of different material types, and do not mix pipe, fittings, or
joining methods from different manufacturers. Combustion exhaust can contain carbon monoxide and
must be properly vented outside. Breathing abnormal amounts of carbon monoxide can result in seri-
ous injury or death.
Description Heater Vent Kits Z-FLEX®
NovaVENT™ Z-VENT™
4" Straight pipe - 6" length 100112407 2NVP4.5 2SVEPWCF0406
4" Straight pipe - 12" length 100112406 2NVP41 2SVEPWCF0401
4" Straight pipe - 24" length 100112404 2NVP42 2SVEPWCF0402
4" Straight pipe - 36" length 100112403 2NVP43 2SVEPWCF0403
4" Straight pipe - 48" length 100112402 2NVP44 2SVEPWCF0404
4" Adjustable straight pipe - 10"-18" adjustability 100112405 2NVAL4 2SVSPA04
4" 45 degree elbow 100112401 2NVE445 2SVEEWCF0445
4" 90 degree elbow 100112400 2NVE490 2SVEEWCF0490
4" Sidewall termination (4"Termination Hood) 100112419 2NVHTX4 2SVSHTX04
4" Vent termination tee 100112547 2NVTT4 2SVSTTF04
4" Rain Cap 100112415 2NVRC4 2SVSRCF04
4" Extreme weather rain cap 100112548 2NVWC4 2SVSHRC04
4" Horizontal drain tee 100112414 2NVHD4 2SVEDWCF04
4" Vertical drain tee 100112413 2NVVD4 2SVEVDP04
4" wall thimble length 4"-7" wall thickness 100112732 2NVWT4 2SVSWTF04
4" wall thimble length 5"-10" wall thickness 100112733 2NVWT4L 2SVSWTEF04
4" 3-in-1 adaptor (F-F adaptor, condensate
drain, & back-flow preventer) 100112585 2NVBFA4 2SVBFDPA04
4" F-F adaptor 100112399 2NVAFF4 2SVEEWCF0445
4" Backflow preventer w/ F-F adaptor 100112416 2NVBFU4 2ZVB04
4" exhaust / 3" intake DV concentric termina-
tion - 5"-10" adjustability 100112550 2NVHTC43S 2SVSHTC43S
4" exhaust / 3" intake DV concentric termina-
tion - 12"-18" adjustability 100112551 2NVHTC43 2SVSHTC43
4" Sidewall termination, adjustable pipe 100187853 2NVBV4 n/a
4" Wall Thimble, 3"-6" wall thickness 100187852 2NVBT4 n/a
Installaon
Installaon Manual

15 Page
-Combuson air supply-
• The guidelines in this section apply to installations within the United States. All
U.S. installations must conform to the National Fuel Gas Code, ANSI Z223.1/NFPA
54 (current edition) and local codes.
• Canadian requirements differ from the guidelines in this section. In Canada,
follow the requirements of B149.1 (Natural Gas and Propane Installation Code,
current edition) as well as local and provincial codes. Contact your local code
enforcement agency for direction.
NOTICE
This gas water heater requires an adequate source of clean air for combustion and
ventilation. Without sufficient air, your water heater may not operate properly and
may emit excessive and abnormal amounts of carbon monoxide which may result
in carbon monoxide poisoning or death.
WARNING
Before installing the water heater, you must determine the amount of air needed to supply this water
-

Check for Chemicals:


these corrosive chemicals is not covered by the warranty.
WARNING!
In all cases, ensure that corrosive chemicals are not present at the air intake. Presence of such chemicals

require outside air due to chemicals include:
 Beauty salons
 Photo processing labs
 Indoor pools
 
 Chemical storage areas
Products such as aerosol sprays, detergents, bleaches, cleaning solvents, gasoline, air fresheners, paint and
varnish removers, and refrigerants should not be stored or used near the water heater.
Does your installation space have sufficient combustion air?








CalculatetotalBTU/hrangofallappliances.
-
ing appliances (e.g., water heaters, furnaces, clothes dryers) in the same area. Do not include appliances
that are direct vented. Refer to the following example.
Installaon
Installaon Manual

16 Page
Your water heater’s BTU/h rating is on the rating plate. The BTU/h ratings should be on the other
appliances’ rating plates. If you have trouble determining the BTU/h ratings, contact the manufacturer
or have a qualified person determine the ventilation requirements.
NOTICE:

Gas Burning Appliance BTU/hRang
Gas Water Heater 199,000
Furnace 75,000
Dryer 20,000
Total 294,000
Example: Gas Burning Appliance BTU/hRang
Gas Water Heater
Total
Your
appliances:
Calculate the air volume of the room
Air requirements depend on the size of the room.
32
If there are large objects in the room (e.g., refrigerator, furnace, car), subtract their volume from the vol-

Air Volume = Room Volume - Object Volume

Calculate required air volume
3
(1.42 m3) per 1,000 BTU/h of the total input for all gas burning appliances in the same area.
33/ 1000 (btu/h)
Example:
3
If the air volume of the room is less than the required air volume, you must direct vent the water heater
-

If the air volume of the room is greater than the required air volume, it may be possible to install the


as furnaces, whole house fans, and clothes dryers draw air out of your home. If they draw air out faster



-
”
Install with outside ventilation


Supplying outside air to the water heater typically requires two openings. One opening must be within 12 in

single opening is not preferred, you may use a single opening to outside air if the minimum free area is sized
according to Table 1


Installaon
Installaon Manual

17 Page
Determine type of ventilation


1. Direct to outdoors
2. 
3. Horizontal ducts
4. Single opening (not recommended; must be at least 100 in2(6.5 cm2
3(1.42 m3
5. From a larger room inside the house (not recommended – refer to "Calculate the air volume of the room"
above to determine if the combined volume of the rooms may be adequate).
Determine minimum free area required for each vent opening

from “Before beginning”) and the type of vent used. Table 1 provides the minimum free area for each vent opening

Calculate minimum size of vent openings and ducts

vents use louvers or grilles to protect the opening. The louver or grill itself blocks some of the free area, so the open-
ing may need to be larger to meet the minimum free area requirements.


2(645 cm2) of free area would need
134 in2(865 cm222).

 
 

 Each vent opening must be no smaller than 100 in2(645 cm2).
 
 Rectangular ducts must have a minimum dimension of no less than 3 in (76 mm).
 All screens must have mesh ¼” or larger.
 -

 
Check that air source is clean and free of chemicals
-


See graphics on next page.
Table 1

indoor spaces.

Opening Source Minimum Free Area
Direct to outdoors* 1 in2(6.5 cm2) per 4,000 BTU/hr (see Figure 1, 2)
 1 in2(6.5 cm2) per 4,000 BTU/hr (see Figure 3)
Horizontal ducts 1 in2(6.5 cm2) per 2,000 BTU/hr (see Figure 4)
Single Opening 1 in2(6.5 cm2) per 3,000 BTU/hr (see Figure 5)
Two permanent openings
to another room**
1 in2(6.5 cm2) per 1,000 Btu/hr (see Figure 6)
Opening: 100 in2 (645 cm2) MIn
Minimum dimension of air openings:
no less than 3 in (76 mm)

an outside wall.
-


Installaon
Installaon Manual

18 Page
Combusonairsupplyopons
Gable vent
to outdoors
Install above
insulaon
Outlet air to
ac 1 in2 (6.5 cm2)
per 4,000 btu/h
Inlet air from
the crawl space
Open foundaon vent
Confined
Space
Alternate
Air Inlet
1 in2 (6.5 cm2)
per 4,000 btu/h
Figure 1 - Direct to outdoors openings
 duct openings
Outlet air to
ac 1 in2(6.5 cm2)
per 4,000 btu/h
Inlet air duct
1 in2 (6.5 cm2)
per 4,000 btu/h
Confined
Space
12” (305 mm)
maximum
Gable vent
to outdoors
Install above
insulaon
Figure 5 - SIngle opening
Confined
Space 1 in2 (6.5 cm2)
per 3,000 btu/h
Alternave
Opening
Locaon
Figure 6 - Two permanent openings
Two permanent
Openings
1 in2 per
1,000 btu/h
12” (305 mm)
maximum
12” (305 mm)
maximum
Confined
Space
Figure 4 - Horizontal duct openings
1 in2 (6.5 cm2)
per 2,000 btu/h
Confined
Space
Outlet
Inlet
Outdoor
Air Ducts
1 in2 (6.5 cm2)
per 2,000 btu/h
Figure 2 - Direct to outdoors openings
Two permanent openings
Two permanent
Openings
1 in
2 (6.5 cm2)
per 4,000 btu/h
12” (305 mm)
maximum
12” (305 mm)
maximum
Confined
Space
Installaon
Installaon Manual

19 Page
-Exhaust venng-
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 350 °F (177 °C). 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 4 in. (102
mm) 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 5 ft (1.5 m), support the vent run at 3 ft (0.9 m) intervals
with overhead hangers.
 When the vent run exceeds 5 ft (1.5 m), a condensate drain is recommended. It should be
installed as close to the heater as possible.
 The maximum length of exhaust vent piping must not exceed 50 ft (15.2 m) (deducting 5 ft (1.5
m) for each elbow used in the venting system). Do not use more than 5 elbows.
Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
4 in. (102 mm) 550 ft (15.2 m )
Each elbow added, deduct 5 ft. (1.5m) from max. vent length.
No. of Elbows Max. Vertical or Horizontal Vent Length
050 ft (15.2 m)
145 ft (13.7 m)
240 ft (12.2 m)
335 ft (10.7 m)
430 ft (9.1 m)
525 ft (7.6 m)
Excludes elbow termination, rain caps, or the 4 in. (102 mm) Concentric termination
Installaon
Installaon Manual

20 Page
-Venng illustraons-
110 Indoor, 310 Indoor, and 510 Indoor models
For details of the optional items, refer to the Installation manual for each Optional item.
HorizontalInstallaonwith
Direct-ventconcentricterminaon
Wall
Direct-vent
concentric

InstallaonofDirect-ventconversionkit
100112184(TK-TV10) with a water heater
Installaon
Installaon Manual
*Backflow preventer (Recommended for freezing weather conditions: 36 °F (2 °C) and below).
**Vertical condensation drain must be installed in accordance with local codes.


VercalInstallaon
(Withdirect-venng)
Roof


preventer* Fire stop

Rain cap
HorizontalInstallaon
(Withdirect-venng)
Sidewall vent


preventer*

drain**
Wall
Hanger
Hanger
HorizontalInstallaon
Hanger
Wall
Sidewall vent
termination
Vertical condensation drain**
Backflow
preventer*
VercalInstallaon
Backflow
preventer*
Rain cap
Roof
Vertical condensation drain**
Roof flashing
Fire stop
Air intake cover plate Remove the air intake
cover plate to attach
the air intake port from
the Direct-vent
conversion kit into there.
Cover the louver of the
water heater with the plate
provided in the Direct-vent
conversion kit to complete
the conversion to sealed
combustion.