A.O. Smith 910 User manual

Gas Tankless Water HeaterTM
Suitable for combination potable water heating
and space-heating
Please refer to local codes
for space-heating compliance.
FEATURING
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On-Demand Water Heater
Installation Manual and Owner’s Guide
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WARNING
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ŝŶƐƚƌƵĐƚŝŽŶƐ ŝƐ ŶŽƚ ĨŽůůŽǁĞĚ
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ƉĞƌƐŽŶĂůŝŶũƵƌLJŽƌĚĞĂƚŚ
<ĞĞƉ ƚŚŝƐ ŵĂŶƵĂů ŶĞĂƌ ƚŚĞ ǁĂƚĞƌ ŚĞĂƚĞƌ ĨŽƌ ĨƵƚƵƌĞ ƌĞĨĞƌĞŶĐĞ ǁŚĞŶĞǀĞƌ ŵĂŝŶƚĞŶĂŶĐĞ ĂĚũƵƐƚŵĞŶƚ Žƌ
ƐĞƌǀŝĐĞŝƐƌĞƋƵŝƌĞĚ
ANSI Z21.10.3・CSA 4.3
For supplying potable
hot water
ASME model ONLY
HLW
Models
910/910 ASME
R
DR

2Page
CONTENTS
Installation Manual
SPECIFICATIONS ......................................................................2
INTRODUCTION.....................................................................4
SAFETY GUIDELINES..............................................................6
SAFETY DEFINITION ............................................................6
GENERAL ..............................................................................6
INSTALLATION .........................................................................7
GENERAL ..............................................................................7
CLEARANCES........................................................................9
INCLUDED ACCESSORIES ....................................................9
OPTIONAL ITEMS ................................................................9
WARNING FOR INSTALLATIONS .......................................11
OUTDOOR INSTALLATIONS...............................................12
Clearances ........................................................................12
INDOOR INSTALLATIONS ..................................................13
Clearances ........................................................................13
Combustion air supply .....................................................13
Direct intake vent system.................................................14
VENTING INSTRUCTIONS .................................................15
General.............................................................................15
Vent length and No. of Elbows.........................................17
Indoor installation diagrams ............................................17
Clearances for sidewall terminations...............................18
Clearances for rooftop terminations................................19
Vent termination clearances ............................................20
GAS SUPPLY AND GAS PIPE SIZING .................................21
General.............................................................................21
Gas connections ...............................................................21
Natural gas supply piping .................................................22
Propane (LP) supply piping...............................................22
WATER CONNECTIONS .....................................................23
Pressure relief valve .........................................................23
ELECTRICAL CONNECTIONS .............................................24
REMOTE CONTROLLER CONNECTION .............................24
EXTERNAL FAN MOTOR CONNECTION............................25
PUMP CONTROL CONNECTIONS .....................................25
Pump control mode .........................................................25
TWO UNIT PRIORITY .........................................................26
^zͳ>/E<^z^dD.................................................................... 27
Easy link connection procedures......................................27
Dh>d/ͳhE/d^z^dD ................................................................ 29
APPLICATIONS.......................................................................30
SPACE HEATING APPLICATIONS .......................................30
RECIRCULATION ................................................................30
h>ͳWhZWK^,KdtdZ,d/E' ..............................31
INITIAL OPERATION ..............................................................32
Owner's Guide
OPERATING SAFETY ..............................................................34
NORMAL OPERATION ...........................................................36
GENERAL ............................................................................36
WITH REMOTE CONTROLLER...........................................36
Set temperature ...............................................................37
Temperature tables of controller .....................................37
Other functions ................................................................37
TEMPERATURE SETTINGS ON THE COMPUTER BOARD ........38
FLOW...................................................................................39
FREEZE PROTECTION SYSTEM..........................................39
MAINTENANCE AND SERVICE ..........................................39
Measuring inlet gas pressure ...........................................40
UNIT DRAINING AND FILTER CLEANING................................40
TROUBLESHOOTING..............................................................41
GENERAL ............................................................................41
ERROR CODES....................................................................43
General.............................................................................43
Error code display.............................................................43
Easy-Link System ..............................................................43
Fault analysis of error code..............................................44
COMPONENTS DIAGRAM .....................................................46
PARTS LIST .............................................................................50
OUTPUT TEMPERATURE CHART ...........................................52
SPECIFICATION
Natural Gas Input
(Operating Range) BTU/H Min: 15,000 BTU/h
Max: 380,000 BTU/h
Propane Input
(Operating Range) BTU/H Min: 15,000 BTU/h
Max: 380,000 BTU/h
Gas Connection 1” NPT
Water Connections 1” NPT
Water Presure* psi
(Mpa)
15 - 150 psi*
(0.1 - 1.0 Mpa)
Natural Gas
Inlet pressure
" W.C.
(kPa)
Min.: 4” W.C.(1.00 kPa)
Max.: 10.5” W.C.(2.61 kPa)
Propane Gas
Inlet pressure
" W.C.
(kPa)
Min.: 8” W.C.(1.99 kPa)
Max:. 14” W.C.(3.48 kPa)
Weight lbs.
(kg)
ϭϬϮůďƐ;ϰϲϯ<ŐͿ
Dimensions Inch
(mm)
H 25.3 in. (643mm) ×
W 24.8 in. (630mm) ×
D 11.8 in. (300mm)
Ignition Electric Ignition
Electric
Supply VAC/Hz 120 VAC/60 Hz
Consumption
Operation W/A 178 W (1.48 A)
Stanby W/A 16 W (0.13 A)
Freeze-
Protection W/A 271 W (2.26 A)
Category Category III
*40 psi (0.28 Mpa) 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 pro-
duction 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 posi-
tive vent static pressure and with a vent gas tempera-
ture that avoids excessive condensate production in
the vent.
Category IV - a water heater that operates with a posi-
tive vent static pressure and with a vent gas tempera-
ture that may cause excessive condensate produc-
tion in the vent.
***These are equivalent lengths that include head loss
for elbows, tees, unions, etc.
NOTE:
ͻ ŚĞĐŬƚŚĞƌĂƚŝŶŐƉůĂƚĞƚŽĞŶƐƵƌĞƚŚĂƚƚŚŝƐƉƌŽĚ-
uct matches your specifications.
ͻ The manufacturer reserves the right to discon-
tinue, or change at any time, specifications or
designs without notice and without incurring
obligation.
Contents

3Page
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů
Installation Manual
CONGRATULATIONS
Congratulations and thank you for choosing our tankless water heater.
Before use, we recommend that you read through this installation
ŵĂŶƵĂůĐĂƌĞĨƵůůLJ<ĞĞƉƚŚŝƐŵĂŶƵĂůĨŽƌĨƵƚƵƌĞƌĞĨĞƌĞŶĐĞ
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
INTRODUCTION
ͻ This manual provides information necessary for the installation, operation, and maintenance of the
water heater.
ͻ The model description is listed on the rating plate which is attached to the side panel.
ͻ Please read all installation instructions completely before installing this product.
ͻ If you have any problems or questions regarding this equipment, consult the manufacturer or its local
representative.
ͻ This appliance is an on-demand, tankless water heater. It is designed to efficiently supply endless hot
water for your needs.
ͻ The 910 has two heat exchangers. The primary and secondary heat exchangers alternate roles, extend-
ing the life of the 910. (See p. 5.)
ͻ The principle behind tankless water heaters is simple:
Heat
exchanger
Exhaust
Burner
Fan Fan
Burner
Heat
exchanger
Gas inlet
Cold water inlet
Hot water inlet
Igniter
Gas valve
Water control valve
Flow sensor
Thermistor Thermistor
Flow
sensor
Thermistor
Computer board
1
8
2
3
3
4
4
5
6
6
7
7
7
7
5
4
4
*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.
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5Page
/ŶƚƌŽĚƵĐƟŽŶ
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů
ŽŵďƵƐƟŽŶƐĞĐƟŽŶƐ
ZŝŐŚƚĐŽŵďƵƐƟŽŶ
ƐĞĐƟŽŶ
>ĞŌĐŽŵďƵƐƟŽŶ
ƐĞĐƟŽŶ
The 910 has two combustion sections. The combustion section that turns on first is the primary section.
The secondary section will activate when the flow rate through the primary section meets the flow listed
in the table below.
Set temperature °F (°C )
Flow rate at which the
secondary section activates
GPM (L/min)
100-120 (38-49) 3.2 (12)
125,130 (52,54) 2.9 (11)
140 (60) 2.6 (9.8)
145,150 (63,65.5) 2.4 (9)
155-185 (68-85) 2.1 (8)
Example:
If the set temperature is 120 °F (49 °C ):
The section(s) in operation is indicated by the black square(s).*
ĞƉĞŶĚŝŶŐŽŶǁŚŝĐŚƐŝĚĞŝƐƚŚĞƉƌŝŵĂƌLJƐĞĐƟŽŶ
910
OR
Total Flow < 0.5 GPM (1.9 L/min.)
(standby) 0.5 GPM (1.9 L/min) < Total Flow < 3.2 GPM (12 L/min.)
;ŽŶůLJƉƌŝŵĂƌLJƐĞĐƟŽŶĮƌĞƐͿ
Total Flow > 3.2 GPM (12 L/min)
;ďŽƚŚƐĞĐƟŽŶƐĮƌĞͿ
910910
910
*The primary and secondary combustion sections will alternate every 100 firing cycles or every 12 hours of opera-
tion.

6Page
SAFETY GUIDELINES
^&dz&/E/d/KE
'EZ>
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:
ͻ Your water heater will have enough combustion air and proper ventilation.
ͻ 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.
^ĂĨĞƚLJ'ƵŝĚĞůŝŶĞƐ
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů
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.
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.
WARNING
ͻ Water temperatures over 125 °F (52 °C) can cause severe burns instantly or death from
scalding. The water temperature is set at 120 °F (50 °C) from the factory to minimize any
scalding risk. Before bathing or showering, always check the water temperature.
ͻ Do not store or use gasoline or other flammables, vapors, or liquids in the vicinity of this appliance.
ͻ 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. 23 when installing your water heater.
ͻ Do not use this appliance if any part has been under water. Immediately contact a
qualified installer or service agency to replace a flooded water heater. Do not attempt
to repair the unit! It must be replaced!
ͻ 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. For more
information, refer to Freeze Protection System on p. 39.
ͻ Failure to observe these warnings can result in serious personal injury or death.
NOTICE

7Page
INSTALLATION
'EZ>
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. 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. Ensure that the vent termination meets
the minimum distance requirements, including minimum clearances from doorways or
openings. (Refer to pp. 18 to 20.) Check local code requirements 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. Refer to "Direct Vent Intake" section
on pp. 14.
9. If the water heater is used as a direct-vent appliance, the unit requires a 5 in. (127 mm)
combustible air supply pipe. The intake pipe must be sealed airtight. Refer to "Venting
instructions" on pp.15 to 20 for more detail.
10. Terminating the venting through a sidewall is recommended for the direct-vent system.
11. Running the exhaust vent and the intake pipe parallel is recommended.
12. 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.
13. Only install the water heater in a heated area where below freezing temperatures cannot
occur. The warranty does not cover damage caused by freezing.
14. The water heater must be securely mounted to a wall or other suitable structure.
/ŶƐƚĂůůĂƟŽŶ
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů

8Page
ͻ The 910 model weighs 102 lbs. (46.3 kg). Ensure that any and all support structures
(whether it is installed on a wall, on a support stand, etc.) have enough strength to
support and hold the water heater.
ͻ When handling the 910, do not place your hands inside the flue collar. Injury may
result.
ͻ Installation and service must be performed by a qualified installer (for example, a
licensed plumber or gas fitter). Otherwise, the warranty will be void.
ͻ 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.
ͻ The manufacturer does not recommend installing the water heater in a pit or location
where gas and water can accumulate.
ͻ Do not have the vent terminal pointing toward any operating window, door, or opening
into a building.
ͻ Do not install the unit where water, debris, or flammable vapors may get into the flue
terminal.
ͻ 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.
ͻ The manufacturer does not suggest installing the water heater in an attic due to
safety issues. If you install the water heater in an attic:
ͻ Make sure the unit will have enough combustion air and proper ventilation.
ͻ <ĞĞƉƚŚĞĂƌĞĂĂƌŽƵŶĚƚŚĞǁĂƚĞƌŚĞĂƚĞƌĂŶĚŝƚƐƚĞƌŵŝŶĂƚŝŽŶĐůĞĂŶtŚĞŶĚƵƐƚ
collects on the flame sensor, the water heater will shut down and produce an
error code.
ͻ If the above conditions cannot be met, use the direct-vent conversion kit
100112186 (TM-DV50).
ͻ Place the unit for easy access for service and maintenance.
ͻ 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 manufacturer is not
responsible for damage due to water leaks.
ͻ Failure to observe these warnings could result in severe personal injury, death, and/or
property damage.
WARNING
ͻ The warranty will not cover damage caused by water quality.
ͻ 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.
ͻ 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.
ͻ Water pH levels must be between 6.5 and 8.5.
ͻ Well water must be treated.
ͻ The manufacturer recommends direct venting 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.
ͻ 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.
ͻ 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.
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NOTICE

9Page
>ZE^
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#Model Indoor Installation Outdoor Installation
1. Remote controller: 100112155 (TM-RE30) ✓
✓
(Remote should be installed
indoors.)
2 Multi-unit Controller: 100112691 (TM-MC02) ✓✓
3.
5" (127 mm) Backflow preventer and F-F adaptor
100112598 ✓
5" (127 mm) Universal Appliance Adaptor, F-F adaptor,
backflow preventer, condensate drain trap
2SVBFDPA05
✓
4. Vent cap: 100112194 (TM-VC50) ✓
5. Direct-vent conversion kit: 100112186 (TM-DV50) ✓
6. Pipe cover: 100112190 (TM-PC50) ✓✓
7.
5" Sidewall vent termination (Hood)
100112594/2NVTH5 ✓
5" Wall thimble
(Refer to the next page.) ✓
8. Direct-vent concentric termination
(Refer to the next page.) ✓
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Installation manual
and Owner’s guide
Communication cable
100076417
Qty: 1
Qty: 1
Installation Top Bottom Front Back Sides
Indoor installation 12 in.
(305 mm)
12 in.
(305 mm)
4 in.**
(102 mm)
1.0 in.
(25 mm)
3 in.
(76 mm)
Outdoor installation 36 in.
(914 mm)
12 in.
(305 mm)
24 in.
(610 mm)
1.0 in.
(25 mm)
3 in.
(76 mm)
*Standard indoor installations and direct-vent indoor installations have the same clearances.
**24 inches recommended for maintenance.
***For the multiple installation of outdoor models, refer to the above clearances.
Maintain all clearances around the water heater.
Failure to do so could create a fire hazard, potentially leading to death, seri-
ous injury, and/or property damage.
WARNING

10 Page
1. Temperature remote controller
100112155 (TM-RE30)
The remote controller has the
following functions:
 adjusts the output tempera-
ture of hot water.
 provides informations of the
flow rate, output tempera-
ture, and so on.
 provides error code when
the water heater has some
trouble.
2. Multi-unit controller
100112691(TM-MC02)
The multi-unit controller can control
a maximum of 10 water heaters,
from 15,000 BTU to 3,800,000 BTU.
It also works as a diagnostic tool that
will give an error code whenever
there is a problem with the water
heater system.
Each multi-unit controller comes
with a remote controller.
3. 5” Backflow preventer
They prevent air
backflow from a
vent system of Nova
Vent line. Install
in accordance with
the installation
instructions that
are packed with the
preventer.
100112598 2SVBFDPA05
4. Vent cap:100112194(TM-VC50)
The cap installed on the top of the water heater for
outdoor installation. It will prevent any debris from
entering the unit and causing damage or a fire haz-
ard, as well as rain.
5. Direct-vent conversion kit: 100112186
(TM-DV50)
The kit can be used to con-
vert to a direct venting system
or sealed combustion system.
Install in accordance with the
manufacturer's installation
instructions and any applicable
codes.
6. Pipe cover: 100112190(TM-PC50)
The pipe cover protects the
plumbing pipes from unex-
pected adjustments. It is
fixed to the bottom of the
water heater and hides the
plumbing and improves the
visial aspects of the whole
installation of the heater.
7. Sidewall vent termination (Hood) and Wall thimble:
They are used when venting out through the wall. These terminations are special stainless steel vents for gas
appliances and are UL listed as Category II, III and IV. For different wall thicknesses, there are two ranges of lengths
available. (Refer to the NovaVent brochure for details.) Install these vent terminations in accordance with their
installation instructions and any applicable local codes.
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8. Concentric Vent Kit:
Covering wall thicknesses Part# Part#
5" Termination Hood 100112594 2NVTH5
5" Wall Thimble 4 - 7 in. (102 - 178 mm) 100112734 2NVWT5
5" Wall Thimble 5 - 10 in. (127 - 254 mm) 100112735 2NVWT5L
Used when terminating direct-vent (sealed combustion) systems, with
indoor models that require a 5 in. (125 mm) intake and a 5 in. (125 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. Threre are two kits for the 5 in. (125 mm)
where the difference is the wall thickness adjustment:
5.0" - 10.0" (127 - 254 mm): 100112606
12.0" - 18.0" (305 - 457 mm): 100112601
(Refer to the Flexmaster brochure for details.)
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11 Page
tZE/E'&KZ/E^d>>d/KE^
FOR YOUR SAFETY, READ BEFORE INSTALLATION:
Do not install the heater where water, debris or
flammable vapors may get into the flue terminal.
This may cause damage to the heater and void the
warranty.
Do not have the vent terminal pointing toward
any opening into a building. Do not locate your
water heater in a pit or location where gas and
water can accumulate.
Do not install this water heater under an
overhang less than 3 ft (914 mm) from its top
or eaves. The area under an overhang must be
open to three sides (Outdoor models only).
Do not install next to a dryer or any source
of airborne debris that can be trapped inside
the combustion chamber, unless the system
is direct-vented. The air intake must maintain
a safe distance from the dryer's exhaust vent.
This will help to prevent lint from being drawn
into the water heater's air intake.
Prohibited Prohibited
3 ft
(914 mm)
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Water heater vent terminator must be at least 2
ft (610 mm) away from an inside corner for both
outdoor installation, indoor single vent, or direct-
vent installation.
Inside
Corner
2 ft
(610 mm)
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h^ϭŌ;ϯϬĐŵͿŵŝŶ
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h^ϭϮŝŶ;ϯϬĐŵͿĂďŽǀĞŐƌĂĚĞĂŶĚ
ĂďŽǀĞĂŶƟĐŝƉĂƚĞĚƐŶŽǁůĞǀĞů
ĂŶĂĚĂϭϮŝŶ;ϯϬĐŵͿĂďŽǀĞŐƌĂĚĞ
ŶƟĐŝƉĂƚĞĚƐŶŽǁůĞǀĞů
Ensure that you meet the minimum clearances
shown below for a direct vent termination:

12 Page
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KhdKKZ/E^d>>d/KE
 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.
 Install outdoors only in areas with mild, temperate climates.
 Change the DIP switch for outdoor installation. Locate the lower banks of DIP switches on the right of
the 7-Seg. LED on the center computer board. (See the graphic below.) The No. 6 ("OUT") DIP switch
on that bank must be switched to its ON position and the No. 5 ("DIRE") DIP switch must be in the
OFF positon. (Do not adjust the upper bank of DIP switches).
 The outdoor vent cap must be used when unit is installed outdoor. The manufacturer requires the use
of its part No. 100112194 (TM-VC50).
 When installed outdoors, the water heater shall be wall-mounted or mounted on a stand. Locate the
water heater in an open, unroofed area and maintain the minimum clearances that are listed at the
bottom of this page.
WARNING
ͻ To change the DIP switch settings for outdoor installation, locate the lower bank of
DIP switches at the bottom of the center computer board as shown below.
ͻ Only adjust the appropriate DIP switches as shwon below.
ͻ Turn off the power supply to the water heater before changing the DIP switch settings.
ͻ Failure to observe this warning could result in carbon monoxide poisoning or death.
ͻ Maintain all clearances around the
water heater. Failure to do so could
create a fire hazard, potentially lead-
ing to death, serious injury, and/or
property damage.
ͻ There is a 3 inch (76 mm) clearance
from the left and right sides of the
unit to combustible and non-com-
bustible surfaces. However, if any
portion or area of the surface is
exposed to the exhaust fumes (i.e.
directly to the sides of the vent cap),
that surface must be at least 24 inch
(610 mm) away.
WARNING
Top
36 in.(914 mm)
Side
24 in.(610 mm)
Side
24 in.(610 mm)
Front
24 in.(610 mm)
Front
24 in.(610 mm)
ŽƩŽŵ
12 in.(305 mm)
Side
3 in.
(76 mm) Side
3 in.
(76 mm)
Back
0.5 in.
(13 mm)
-Clearances-
ON
MST P-ALARM OUT DIRE MODE TMP3 TMP2 TMP1
87654321
The dark squares indicate the correct
positions of DIP switches.
The lower bank of DIP switches
ON
OFF

13 Page
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-Clearances-
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
Top
12 in.(305 mm)
Front 4 in.(102 mm)
24 in. (610 mm)
Recommended
for maintenance
ŽƩŽŵ
12 in.(305 mm)
Side
3 in.
(76 mm) Side
3 in.
(76 mm)
Back
0.5 in.
(13 mm)
-Combustion air supply-
The water heater location must provide enough air for proper combustion and ventilation of the surrounding
area. See the current edition of ANSI Standard Z223.1 or any applicable local codes. In general, these require-
ments specify that if the unit is installed in a confined space, there must be a permanent air supply opening.
Minimum recommended air supply opening size for water heater:
Water heater size When drawing make-up air from out-
side the building
When drawing make-up air from inside the
building (from other rooms within)
Max.
380,000 BTU/h
25.3 in2 (163.2 cm2) 380 in2 (2451.6 cm2)
When combustion air is supplied
from outside the building, an open-
ing communicating directly with the
outside should have a minimum free
area of one square inch per 15,000
BTUH input of the total input rating
of water heater in the enclosed area.
When combustion air is supplied from inside
the building, an opening communicating with
the rest of the dwelling should have a minimum
free area of one square inch per 1,000 BTUH
input of the total input rating of water heater in
the enclosed area. This opening should never be
less than 199 in2 (1283.9 cm2).
ON
MST P-ALARM OUT DIRE MODE TMP3 TMP2 TMP1
87654321
The dark squares indicate the cor-
rect positions of DIP switches.
Lower bank of DIP switches
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 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.
 Do not change the DIP switch settings for indoor installations. The DIP switch settings were already
set at the factory. Make sure the No. 5 ("DIRE") and No. 6 ("OUT") DIP switches are in the OFF posi-
tion. (These switches are located on the lower bank of DIP switches as shown below.)
 For venting instructions for indoor installations, refer to pp. 15 to 20.

14 Page
Combustible air supplied by mechanical fan or make up air device
The water heater is equipped with a combustible air sensor that will shut off the unit when inadequate com-
bustible air supply to unit is detected.
 If a mechanical fan or make up air device is used to supply air to the water heater or utility room, the
installer should make sure it does not create drafts which could cause nuisance shutdowns.
 If a blower is necessary to provide adequate combustion air to the water heater, the blower and water
heater must be set up so that the water heater cannot fire unless the blower is operating. Possible
methods include the use of the water heater internal fan control port or the use of external flow sensors/
transmitters and relays.
-Direct intake vent system-
This water heater may be converted to a direct-vent (sealed combustion) appliance by installing an adapt-
er 100112186 (TM-DV50) which will bring all required combustible air from outside the building. When
installing the direct-vent conversion kit, please follow all instructions included with the kit.
 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.
 If used as a direct-vent appliance, the water heater
requires a 5” (127 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), galvanized steel, corrugated aluminum,
corrugated stainless steel or Category III 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.
 Change the DIP switch settings to the direct-vent system.
(See diagram below.)
 Sidewall venting is recommended for the direct-vent
system.
 The manufacturer recommends running the exhaust vent
and the intake pipe parallel.
 For the venting instructions for direct intake vent installa-
tions, refer to pp. 15 to 20.
5”Intake air port Exhaust
Louver cover plates
Direct vent
conversion kit
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WARNING
ͻ To change the DIP switch settings for direct vent installation, locate the lower bank of
DIP switches at the bottom of the center computer board as shown below.
ͻ Only adjust the appropriate DIP switches as shwon below.
ͻ Turn off the power supply to the water heater before changing the DIP switch settings.
ͻ Failure to observe this warning could result in carbon monoxide poisoning or death.
ON
MST P-ALARM OUT DIRE MODE TMP3 TMP2 TMP1
87654321
The dark squares indicate the correct
positions of the DIP switches.
The lower bank of DIP switches
ON
OFF

15 Page
sEd/E'/E^dZhd/KE^
For indoor installations
-General-
ͻ Improper venting of this appliance can result in excessive levels of carbon monoxide
which can result in severe personal injury or death.
ͻ Improper installation can cause nausea or asphyxiation, severe injury or death from
carbon monoxide and flue gases poisoning. Improper installation will void product
warranty.
ͻ 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.
WARNING
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, and Section 8 of B149.1 Natural Gas in Canada, 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. 16.
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.
ͻ The air intake can use 5" PVC (solid core), CPVC (solid core), ABS, or category III vent.
ͻ 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.
ͻ Ensure that the installation location has sufficient, clean combustion air. If unsure, direct vent the
heater with the direct vent conversion kit 100112186 (TM-DV50).
Direct venting installation:
ͻ 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. 17.
ͻ When the horizontal air intake exceeds more then 5 ft, support the pipe every 3 ft with pipe hangers.
ͻ Vertical air intake pipe must be supported with pipe hangers. Ensure that the weight of the pipe
is not carried by the water heater.
General rules for venting water heaters are:
ͻ Place the water heater as close as possible to the vent termination.
ͻ The vent collar of the water heater must be fastened directly to an unobstructed vent pipe.
ͻ Do not weld the vent pipe to the water heater’s vent collar.
ͻ Do not cut or alter the shape of the vent collar of the unit.
ͻ The vent must be easily removable from the top of the water heater for normal service and
inspection of the unit and vent system.
ͻ The water heater vent must not be connected to any other gas appliance or vent stack.
ͻ Avoid using an oversized vent pipe or using extremely long runs of pipe.
ͻ For rooftop venting, a rain cap or other form of termination that prevents rain water from
entering into the water heater must be installed.
ͻ Do not common vent or connect any vent from other appliances to the water heater vent.
ͻ The manufacturer will not be responsible for any damage to the water heater caused by
condensation from the vent. For horizontal runs, slope the vent run downwards toward the
vent terminal at a rate of ¼” per foot (6.4mm per 305mm). For horizontal runs that do not slope
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16 Page
downward and for vertical runs, installing a condensate drain is recommended. Please refer to
pp. 17 and 18 for the diagrams.
ͻ A backflow preventor should be installed in the exhaust when the heater is installed in climates
subject to freezing temperatures.
General rules for vent terminations:
ͻ 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.
ͻ 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
level, but the installer may determine if it should be higher depending on the job site condition
and applicable codes.
ͻ A proper sidewall termination is required when the water heater is vented through a sidewall.
ͻ Refer to the following pages for exhaust termination and air inlet clearances.
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™
5" Air intake hood 100112579 2FAIGAL05
5" Gear clamp N/A 7HS84X
5" Straight pipe - 6" length 100112580 2NVP5.5
5" Straight pipe - 1' length 100112581 2NVP51
5" Straight pipe - 2' length 100112582 2NVP52
5" Straight pipe - 3' length 100112583 2NVP53
5" Straight pipe - 4' length 100112584 2NVP54
5" Adjustable straight - 10"-18" length 100112585 2NVALS5
5" 45 degree elbow 100112586 2NVE545
5" 90 degree elbow 100112587 2NVE590
5" Wall thimble (4"-7") 100112734 2NVWT5
5" Wall thimble (5"-10") 100112735 2NVWT5L
5" Horizontal drain pipe 100112588 2NVHD5
5" Vertical drain pipe 100112589 2NVVD5
5" Storm collar 100112590 2NVSC5
5" Firestop 100112591 2NVFS5
5" Flat roof flashing 100112592 2NVFF5
5" Angled roof flashing 100112593 2NVAF5
5" Termination hood 100112594 2NVTH5
5" Termination tee 100112595 2NVTT5
5" Extreme weather rain cap 100112596 2NVWC5
5" Universal appliance adaptor - 3-in-1 (F-F adaptor, condensate drain, &
back-flow preventer 100112597 2NVBFA5
5" Back-flow preventor & F-F adaptor 100112598 2NVBFU5
5" F-F adaptor 100112599 2NVAFF5
5" Support strap 100112600 2NVSS51
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17 Page
-Vent length and No. of Elbows-
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 350 °F (177 °C). For best results, a vent system should be as short
and straight as possible.
ͻ This water heater is a Category III appliance and must be vented accordingly with any 5 in. (127 mm) vent
approved for use with Category III or Special BH type gas vent.
ͻ Follow the vent pipe manufacturer’s instructions when installing the vent pipe.
ͻ 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.)
ͻ 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.
ͻ The maximum length of exhaust vent piping must not exceed 50 ft (15.2 m).* Deduct 5 ft (1.5 m) for each
90° elbow used in the venting system. Do not use more than 5 elbows. A 45° elbow is equivalent to 2.5
ft. of vent length.
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Vent type Diameter Max. No. of Elbows Max. Vertical and Horizontal (Total) Vent Length
Intake 5 in. (127 mm) 5 50 ft (15.2 m )*
Exhaust 5 in. (127 mm) 5 50 ft (15.2 m )*
*For each 90° elbow added, deduct 5 ft. (1.5m) from max. vent length.
No. of Elbows Max. Vertical or Horizontal
Vent Length No. of Elbows Max. Vertical or Horizontal Vent Length
0 50 ft (15.2 m) 3 35 ft (10.7 m)
1 45 ft (13.7 m) 4 30 ft (9.1 m)
2 40 ft (12.2 m) 5 25 ft (7.6 m)
Excludes elbow termination, rain caps, or the 5 in. (127 mm) Concentric termination.
Standard Vent Terminations
-Indoor installation diagrams-
Single Pipe with Room-Air Intake
*Backflow preventer (Recommended for freezing weather conditions:
36 °F (2 °C) and below).
**Vertical condensation drain must be installed in accordance with
local codes.
sĞƌƟĐĂů/ŶƐƚĂůůĂƟŽŶ
Roof
ŇĂƐŚŝŶŐ
Roof
Fire stop
Hanger
Vertical
condensation
drain**
Backflow
preventer*
Rain cap
,ŽƌŝnjŽŶƚĂů/ŶƐƚĂůůĂƟŽŶ
Wall
Sidewall vent
ƚĞƌŵŝŶĂƟŽŶ
Vertical
condensation
drain**
Backflow
preventer*
Hanger

18 Page
ŝƌĞĐƚǀĞŶƚŝŶƐƚĂůůĂƟŽŶƐ
sĞƌƟĐĂů/ŶƐƚĂůůĂƟŽŶ
Roof
ŇĂƐŚŝŶŐ
Roof
Fire stop
Hanger
Vertical condensation
drain**
Backflow preventer*
Rain cap
,ŽƌŝnjŽŶƚĂů/ŶƐƚĂůůĂƟŽŶ
Wall
Sidewall vent
ƚĞƌŵŝŶĂƟŽŶ
Vertical condensation drain**
Back flow preventer*
Hanger
/ŶƐƚĂůůĂƟŽŶ
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů
-Clearances forƐŝĚĞǁĂůůƚĞƌŵŝŶĂƟŽŶƐͲ
NOTE: Refer to page 14 for the correct DIP switch settings.
Exhaust and/
or direct
vent sidewall
terminations
should be at least
2 ft (610 mm) away
from an opposite
surface/wall. Do
not place the
termination directly
in front of an opening
into a building.
ŶƟĐŝƉĂƚĞĚ^ŶŽǁůĞǀĞů
džŚĂƵƐƚ
dĞƌŵ ŝŶĂƟŽŶ
ϮŌ
;ϲϭϬŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
/ŶƐŝĚĞ
ĐŽƌŶĞƌ
Exhaust
termination
2 ft(610 mm) min.
Inside
corner
ŶƟĐŝƉĂƚĞĚ^ŶŽǁůĞǀĞů
ϮŌ
(610 mm)
min.
ϭŌ
(305 mm)
min.
ϭŌ
(305 mm)
min.
Combined
ŝŶƚĂŬĞĂŶĚ
ĞdžŚĂƵƐƚ
ƚĞƌŵŝŶĂƟŽŶ
Multiple Sidewall Terminations
An exhaust termination must be
at least 1 ft (305mm) away from
another exhaust termination. An
exhaust termination must also be
at least 2 ft (610 mm) away from
an inside corner. (If the adjacent
wall is less than 2 ft (610 mm) of
length, the minimum required
distance away from the inside
corner will be equal to the length
of that adjacent wall.)
Multiple DV Sidewall
Terminations
A direct vent (DV) termination
must be at least 1 ft (305 mm)
away from other direct vent
terminations.
A direct vent termination must
also be at least 2 ft (610 mm)
away from an inside corner. (If
the adjacent wall is less than
2 ft (610 mm) of length, the
minimum required distance
away from the inside corner will
be equal to the length of that
adjacent wall.)
*Backflow preventer (Recommended for freezing weather conditions:
36 °F (2 °C) and below).
**Vertical condensation drain must be installed in accordance with
local codes.
Improper installation can result in carbon monoxide poisoning or death. Follow all local
and national codes in regards to proper termination clearances. In the absence of such
codes, the clearances below must be met. Local codes supersede these clearances.
Failure to observe this warning may result in severe personal injury or death.
WARNING
Direct vent sidewall
terminations
that use two separate
penetrations for
the intake and
exhaust, distance the
intake and exhaust
terminations at
least 3 ft (915 mm)
away from each
other, no matter the
orientation.
ŶƟĐŝƉĂƚĞĚ^ŶŽǁůĞǀĞů
ϯŌ
;ϵϭϱŵŵͿ
ŵŝŶ
ϯŌ
;ϵϭϱŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ŝƌƐƵƉƉůLJ
ŝŶůĞƚ
ŝƌƐƵƉƉůLJ
ŝŶůĞƚ
ŝƌƐƵƉƉůLJ
ŝŶůĞƚ
džŚĂƵƐƚ
ƚĞƌŵŝŶĂƟŽŶ

19 Page
/ŶƐƚĂůůĂƟŽŶ
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů
ͲůĞĂƌĂŶĐĞƐĨŽƌƌŽŽŌŽƉƚĞƌŵŝŶĂƟŽŶƐͲ
ͻ Exhaust terminations must be at least 1 ft (305 mm) away from any obstructions.
ͻ Minimum spacing between multiple terminals:
ͻ intake terminals: 1 ft (305 mm) spacing between each
ͻ exhaust terminals: 1 ft (305 mm) spacing between each
ͻ The exhaust termination must be a horizontal distance of at least 2 ft (610 mm) from a
wall or surface unless specified differently by local code.
ͻ Failure to observe this warning may result in severe personal injury or death.
WARNING
Flat roof terminationAngled roof termination
sĞƌƟĐĂůǁĂůů
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ϮŌ
;ϲϭϬŵŵͿ
ŵŝŶ
ϮŌ
;ϲϭϬŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
ϯŌ;ϵϭϰŵŵͿŵŝŶ
Exhaust gas
Exhaust gas
Intake air
Intake air
ŶƟĐŝƉĂƚĞĚƐŶŽǁůĞǀĞů
ϭŌ
;ϯϬϱŵŵͿ
ŵŝŶ
Multiple flat roof terminations
Exhaust
gas
Exhaust
gas
Intake air
Intake air
ϭŌ
(305 mm)
min.
ϭŌ
(305 mm)
min.
ϭŌ
(305 mm)
min.
ϭŌ
(305 mm)
min.
ŶƟĐŝƉĂƚĞĚƐŶŽǁůĞǀĞů
ϭŌ
(305 mm)
min.
ϮŌ;ϲϭϬŵŵͿŵŝŶ
Multiple angled roof terminations
ͻ In lieu of using roof caps, a 90 degree elbow and 45 degree elbow can be used for the exhaust, and
two 90 degree elbows can be used for the air intake.
3 ft (914 mm) min.
1 ft
(305 mm) min.
1 ft
(305 mm) min.
Intake air
Exhaust
gas
Anticipated
snow level
2 ft (610 mm) min.
1 ft
(305 mm) min.
1 ft
(305 mm) min.
Intake air
Exhaust
gas
Anticipated
snow level
Improper installation can result in carbon monoxide poisoning or death. Follow all local
and national codes in regards to proper termination clearances. In the absence of such
codes, the clearances below must be met. Local codes supersede these clearances.
Failure to observe this warning may result in severe personal injury or death.
WARNING
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

20 Page
/ŶƐƚĂůůĂƟŽŶ
/ŶƐƚĂůůĂƟŽŶDĂŶƵĂů
ͲsĞŶƚƚĞƌŵŝŶĂƟŽŶĐůĞĂƌĂŶĐĞƐͲ
H
D
E
L
B
V
V
V
V
B
F
CB
B
B
V
V
V
V
V
X
X
AJ
M
Operable
Fixed
closed
Fixed
closed
Operable
B
Inside corner
detail
G
A
K
V
X
= Vent terminal
= Air supply inlet
= Area where the terminal
ŝƐŶŽƚƉĞƌŵŝƩĞĚ
Regulator/Gas meter
vent outlet
I
Canada Installations1US Installations2
Direct vent and other than
direct vent
Direct
vent
Other than
directdvent
A Clearance above grade, veranda, porch, deck, or balcony 1 ft (30 cm) 1 ft (30 cm)
B Clearance to window or door that may be opened 3 ft (91 cm) 1 ft
(30 cm)
4 ft (1.2 m) below or to
side of opening; 1 ft (30
cm) above opening
C Clearance to permanently closed window 0 0 0
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
3 ft (91 cm) 3 ft
(91 cm) 3 ft (91 cm)
E Clearance to unventilated soffit 3 ft (91 cm) 3 ft
(91 cm) 3 ft (91 cm)
F Clearance to outside corner 2 ft (61 cm) 2 ft
(61 cm) 2 ft (61 cm)
G Clearance to inside corner 2 ft (61 cm) 2 ft
(61 cm) 2 ft (61 cm)
HClearance to each side of center line extended above
meter/regulator assembly 3 ft (91 cm) * *
I Clearance to service regulator vent outlet
Above a regulator within 3
ft (91 cm) horizontally of the
vertical center line of the
regulator vent outlet to a
maximum vertical distance of
15 ft (4.5 m)
**
JClearance to non-mechanical air supply inlet to build-
ing or the combustion air inlet to any other appliance. 3 ft (91 cm) 1 ft (30 cm)
4 ft (1.2 m) below or to
side of opening; 1 ft (30
cm) above opening
<Clearance to mechanical air supply inlet 6 ft (183 cm) 3 ft (91 cm) above if within
10 ft (3 m) horizontally.
LClearance above paved sidewalk or paved driveway
located on public property 7 ft (213 cm)** 7 ft (213 cm) 7 ft (213 cm)
M Clearance under veranda, porch deck, or balcony 1 ft (30 cm)*** 1 ft (30
cm)*** 1 ft (30 cm)***
*Clearances in accordance with local installation codes and the requirements of the gas supplier.
**A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings
and serves both dwellings.
***Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
Notes:
1) /ŶĂĐĐŽƌĚĂŶĐĞǁŝƚŚƚŚĞĐƵƌƌĞŶƚ^ϭϰϵϭ Natural Gas and Propane Installation Code
2) /ŶĂĐĐŽƌĚĂŶĐĞǁŝƚŚƚŚĞĐƵƌƌĞŶƚE^/ϮϮϯϭE&Wϱϰ, National Fuel Gas Code