Noritz NRC661-DV User manual

Potential dangers from accidents during installation and use are divided into the following three
categories. Closely observe these warnings, they are critical to your safety.
Prohibited Disconnect
Power Ground Be sure to do
WARNING: If the information in this manual is not followed exactly, a re or explosion may result
causing property damage, personal injury or death.
NORITZ AMERICA
CORPORATION
Installation Manual
CONDENSING TANKLESS GAS WATER HEATER
NRC661-DV (Indoor Installation)
DANGER indicates an imminently hazardous situation which,
if not avoided, will result in death or serious injury.
WARNING indicates a potentially hazardous situation which,
if not avoided, could result in death or serious injury.
CAUTION indicates a potentially hazardous situation which,
if not avoided, may result in minor or moderate injury.
DANGER
WARNING
CAUTION
SBB801K
Rev. 01/13
Requests to Installers
• In order to use the water heater safely, read this installation manual carefully, and follow the in-
stallation instructions.
• Failures and damage caused by erroneous work or work not as instructed in this manual are not
covered by the warranty.
• Check that the installation was done properly in accordance with this Installation Manual upon completion.
• After completing installation, please either place this Installation Manual in a plastic pouch and
attach it to the side of the water heater (or the inside of the pipe cover or recess box if applicable),
or hand it to the customer to retain for future reference. Also, be sure to ll in all of the required
items on the warranty and to hand the warranty to the customer along with the Owner's Guide.
CAUTION
FOR USE IN RESIDENTIALAPPLICATIONS.
Installation must conform with local codes, or in the absence of
local codes, the National Fuel Gas Code, ANSI Z223.1/NFPA
54- latest edition and/or CSA B149.1, Natural Gas and Pro-
pane Installation Code (NSCNGPIC).
Noritz America reserves the right to discontinue, or change at
any time, the designs and/or specications of its products with-
out notice.
CERTIFIED
R
Low NOx
Approved by
SCAQMD
14 ng/J or 20 ppm
(Natural Gas Only)
*SBB801K*

2
1.
Included Accessories
The following accessories are included with the unit.
Check for any missing items before starting installation.
Q’ty
ShapePart
Tapping Screw 1
each
Part Shape Q’ty
5
1
Remote Controller
(See p. 30) Remote Controller
Cord (10ft (3m))
1
2.
Optional Accessories
The accessories listed below are not
included with the units, but may be necessary
for installation.
Q’ty
ShapePartPart Shape Q’ty
Remote Controller
Cord (26ft (8m)) 1
1
each
IsolationValves
(includes pressure
reliefvalve)
Owner's Guide, Warranty,
Installation Manual
(this document)
Bird Screen for
3" (75mm) PVC
VT3-PVCS 2
3" (75mm)
PVC Terminal
VK3-H-PVC 1
1
Pipe Cover
(PC-1S)
Note: Additional vent pieces are available; consult the latest product catalogue for details.
3" (75mm)
Horizontal Hood
Termination PVT-HL 2
1
each
SVConversionKit
(#SV-CK-3)
•90 Elbow
(WithInletScreen)
• Installation Manual
(CheckList)
1
Neutralizer
(NC-1)

3
Check the Gas
• Check that the rating plate indicates the
correct type of gas.
• Check that the gas supply line is sized for
120,000Btuh.
Check the Power
• The power supply required is 120VAC, at 60Hz.
Using the incorrect voltage may result in re or electric shock.
Use Extreme Caution if Using With a Solar Pre-Heater
• Using this unit with a solar pre-heater can lead to unpredictable output temperatures and
possibly scalding. If absolutely necessary, use mixing valves to ensure output temperatures do
not get to scalding levels.
120,000
111,000
1.3 / 2.2
2.4"2.4"
1.3 / 2.2
115,700
107,000
120,000 BTU
15,000 BTU 133 4.0
1.0 2.4"
10.5"
505
ANSI Z21.10.3-2011/CSA 4.3-2011
15 150
2
NRC661-DV (eco TOUGH)
3. Before Installation
Checkup
• Check the xing brackets and vent pipe yearly for damage or wear. Replace if necessary.
DANGER
Do Not Use Equipment for Purposes Other Than Those Specied
• Do not use for other than increasing the temperature of the water supply, as unexpected accidents
mayoccurasaresult.
Check Water Supply Quality
• If the water supply is in excess of 12 grains per gallon (200 mg/L) of hardness, acidic or otherwise
impure, treat the water with approved methods in order to ensure full warranty coverage.
WARNING
CAUTION
Precautions on Vent Pipe Replacement
• The vent system will almost certainly need to be replaced when this appliance is being installed.
Only use vent materials that are specied in this Installation Manual for use on this appliance. Refer
to the "Vent Pipe Installation" section for details. If PVC, CPVC, or Category IV listed pipe is already
installed, check for punctures, cracks, or blockages and consult with the vent pipe manufacturer
beforereusing.
Improper venting may result in res, property damage or exposure to Carbon Monoxide.
Snow Precaution
• If this product will be installed in an area where snow is known to accumulate, protect the vent
terminationfromblockagebysnowdriftsordamagefromsnowfallingoffof roofs.

4
4. Choosing Installation Site
* Locate the appliance in an area where leakage from the unit or connections will not result in damage
to the area adjacent to the appliance or to the lower oors of the structure. When such locations
cannot be avoided, it is recommended that a suitable drain pan, adequately drained, be installed
under the appliance. The pan must not restrict combustion air ow.
• Locate the vent terminal so that there are no obstacles around the termination and so that exhaust
can't accumulate. Do not enclose the termination with corrugated metal or other materials.
• Avoid places where res are common, such as those where gasoline,
benzene and adhesives are handled, or places in which corrosive gases
(ammonia, chlorine, sulfur, ethylene compounds, acids) are present.
Using the incorrect voltage may result in re or cracking.
• Avoid installation in places where dust or debris will accumulate.
Dust may block the air-supply opening, causing the performance of the
device fan to drop and incomplete combustion to occur as a result.
• Avoid installation in places where special chemical agents
(e.g., hair spray or spray detergent) are used.
Ignition failures and malfunction may occur as a result.
• Carbon Monoxide Poisoning Hazard. Do not install this water heater in a
mobile home, recreational vehicle or on a boat.
• The water heater is designed for indoor installation only. Never install it
outdoors or in a bathroom, it may be damaged or a re may be caused.
• Consult with the customer concerning the location of installation.
• Install the water heater in an area that allows for the proper clearances
to combustible and noncombustible construction. Consult the rating
plate on the appliance for proper clearances.
• Do not install the water heater in a place where it may be threatened by
falling objects, such as under shelves.
• The water heater must be installed in a place where supply and exhaust
pipes can be installed as directed.
• Do not install the water heater where the exhaust will blow on outer walls
or material not resistant to heat. Also consider the surrounding trees and
animals.
Theheatandmoisturefromthewaterheatermaycausediscolorationof
wallsandresinousmaterials,orcorrosionofaluminummaterials.
DANGER
WARNING
CAUTION
Prohibited
Prohibited

5
• Avoid installation above gas ranges or stoves.
• Avoid installation between the kitchen fan and stove. If oily
fumes or a large amount of steam are present in the installation
location, take measures to prevent the fumes and steam from
entering in the equipment.
• Install in a location where the exhaust gas ow will not be affected
by fans or range hoods.
• Take care that noise and exhaust gas will not affect neighbors.
Avoid installation on common walls as the unit will make some
operational noises while it is running.
• Before installing, make sure that the exhaust ue termination will
have the proper clearances according to the National Fuel Gas
Code(ANSIZ223.1).
State of California: The water heater must be braced, anchored or strapped to avoid moving during an
earthquake. Contact local utilities for code requirements in your area or call: 1-866-766-7489 and
request instructions.
Be sure to do
Prohibited
Prohibited
CAUTION
The Commonwealth of Massachusetts: The water heater can be used for hot water only and not in a
combination of domestic and space heating.
For Venting Manufacturers Requirements, see websites listed below:
Noritz N-Vent www.noritz.com

6
5. Installation Clearances
Before installing, check for the following:
Install in accordance with relevant building and mechanical codes, as well as any local, state or
national regulations, or in the absence of local and state codes, to the National Fuel Gas Code
ANSI Z223.1/NFPA 54 – latest edition. In Canada, see NSCNGPIC for detailed requirements.
WARNING
Item
Distance from combustibles
• Maintain the following clearances
from both combustible and
non-combustible materials.
Check Illustration
• If possible, leave 8" (200mm) or more
on either side of the unit to facilitate
inspection.
• If possible, leave 24" (600mm) or more in
front of the unit to facilitate maintenance
and service if necessary.
• If possible, leave 3" (75mm) or more
above and below the vent pipe to facilitate
inspection and repair if necessary.
Securing of space for
repair/inspection
24" (600mm)
or more
Distance from the side
12" (300mm) or more
2" (50mm) or more
4" (100mm) or more
3" (75mm) or more
3" (75mm) or more
8" (200mm)
or more
8" (200mm)
or more
<When the indoor air supply>
• If the unit will be installed in the vicinity of
a permanent kitchen range or stove that
has the possibility of generating steam
that contains fats or oils, use a dividing
plate or other measure to ensure that the
unit is not exposed to air containing such
impurities.
* The dividing plate should be of noncombustible
material of a width greater than the water
heater.
Exhaust hood
Range
Dividing plate Water
heater
Cooking Equipment
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.

7
Clearance Requirements from Vent Terminations to Building Openings
<When supplying combustion air from the indoors>
* All clearance requirements are in accordance with ANSI Z21.10.3 and the National Fuel Gas Code,
ANSI Z223.1 and in Canada, in accordance with NSCNGPIC.
Item
• There must be a clearance of 24" (600mm)
or more in front of the Flue terminal.
• This restriction will not be applied to an
area where an effective shield makes a
clearance of 24" (600mm) or more in
front of the exhaust outlet.
Check Illustration
Outdoor Clearances to Opening
into Any Building
12" (300mm)
or more
12" (300mm)
or more
There must be no
building opening
within this area.
Flue terminal
12" (300mm)
or more
12" (300mm)
or more
Vent Clearances When Heater is In-
stalled Indoors
For installations in the USA,
• 4' below, 4' horizontally from, or 1'above any
door, operable window, or gravity air inlet into
any building.
3' above any forced air inlet within 10'.
For installations in the Canada,
• 36" (900mm) below, horizontally from, or
above any door, operable window, or gravity
air inlet into any building.
6' (1.8m) from any forced air inlet.
Maintain the following clearances to any
opening in any building: Illustration
4' *
4' *
3' *
1' *
* Clearances for USA only.
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.
Clearance Requirements from Vent Terminations to Building Openings
<When supplying combustion air from the outdoors>
* All clearance requirements are in accordance with ANSI Z21.10.3 and the National Fuel Gas Code,
ANSI Z223.1 and in Canada, in accordance with NSCNGPIC.

8
Vent Terminal
Clearance
A= Above grade, veranda, porch, deck,
or balcony
B= Window or door that may be opened
C= Permanently closed window
D=
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet from the
center of the terminal *
E= Unventilated soffit *
F= Outside corner *
G= Inside corner *
H= Each side of center line extended
above meter/regulator assembly
3' (0.9m) within a height 15' (4.5m)
above meter/regulator assembly
I= Service regulator vent outlet 3' (0.9m)
J= Nonmechanical air supply inlet or
combustion air inlet to any other
appliance
K= Mechanical air supply inlet 3' above if within
10' [6' (1.8m)]
L= Above paved sidewalk or paved
driveway located on public property
Under veranda, porch, deck, or
balcony
* [7' (2.1m***)]
M=
[ ] = indicates clearances required in Canada
*Maintain 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.
* [12" (300mm)****]
*
12" [12" (300mm)]
4’ (1.2m) below or to the side of
opening, or 1’ (0.3m)above opening
[36" (900mm)]
Air Supply Inlet
Area Where Terminal
is Not Permitted
Indoor Combustion Air
*
*
*
*
3' (0.9m) within a height 15' (4.5m)
above meter/regulator assembly
3' (0.9m)
3' above if within
10' [6' (1.8m)]
* [7' (2.1m***)]
* [12" (300mm)****]
*
12" [12" (300mm)]
12" [36" (900mm)]
4’ below or to the side of
opening, or 1’ above opening
[36" (900mm)] 12" [36" (900mm)]
Outdoor Combustion Air
(Direct Vent)
Clearance Requirements from Vent Terminations to Building Openings
* All clearance requirements are in accordance with ANSI Z21.10.3 and the National Fuel Gas Code,
ANSI Z223.1 and in Canada, in accordance with NSCNGPIC.

9
6. Installation
Securing to the wall
IllustrationCheck
4. Drill holes for the remaining four screws.
5. Hang the unit again by the rst screw, and then
insert and tighten the remaining four screws.
6. Take waterproong measures so that water does
not enter the building from screws mounting the
device.
• Make sure the unit is installed securely so that it will
not fall or move due to vibrations or earthquakes.
1. Drill a single screw hole, making sure to hit a stud.
2. Insert and tighten the screw and hang the unit by
the upper wall mounting bracket.
3. Determine the positions for the remaining four screws
(two for the top bracket and two for the bottom), and
remove the unit.
• The weight of the device will be applied to the wall. If the strength of the wall is not sufcient,
reinforcement must be done to prevent the transfer of vibration.
• Do not drop or apply unnecessary force to the device when installing. Internal parts may
be damaged and may become highly dangerous.
• Install the unit on a vertical wall and ensure that it is level.
Locating Screw Holes
Mounting
Structure
• When installing with bare hands, take caution to
not inict injury.
• Be careful not to hit electrical wiring, gas, or water
piping while drilling holes.
Item
CAUTION
Be sure to do
Mounting Bracket
(upper)
Location of Screw Hole
Locating Screw Holes
Installations at Elevations
Above 2,000 ft.
• Adjust the DIP switches as illustrated in the table to
the right if this water heater is installed at an altitude
of 2000 ft. (610m) or higher.
• Disconnect power to the water heater before changing
the DIP switches. Failure to perform this step will result
in a "733" code displayed on the Display Window and
a cease in operation. If this occurs, disconnect, then
reconnect power to the water heater to reset the system.
Tapping Screw
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.
* Do not change any other DIP switches.
* High elevation adjustment.65
2,001 - 4,000 ft (611 - 1,220m)
0 - 2,000 ft (0 - 610m)
ON= OFF=
4,001 - 6,000 ft (1,221 - 1,830m)
6,001 - 8,000 ft (1,831 - 2,440m)

10
Filling the condensate trap with water
DANGER
When initial start up, make sure that you perform the following procedures.
This is to prevent dangerous exhaust gases from entering the building.
Failure to following procedure could result in severe personal injury or death.
After installing the drain pipe, make sure that the area around the unit is well ventilated; open a window or a
door if necessary. Then, operate the unit and verify that condensate is coming out of the drain pipe. (During
normal use of the unit, condensate will begin to discharge from the drain pipe within 15 minutes of use.
However, depending on the season and/or installation site conditions, it may take longer.)

11
Maximum Vent Lengths
• This appliance has been designed to be vented
with either 3" (75mm) PVC or CPVC pipe.
Do not exceed the following maximum vent lengths:
* Not including the termination
• Maintain the same vent pipe diameter from the
heater ue to the vent termination. The exhaust
and intake pipes must be the same vent pipe
diameter.
7. Vent Pipe Installation(Indoor Installation Only)
WARNING
Be sure to do
CARBON MONOXIDE POISONING
Follow all vent system requirements in accordance with relevant local or state regulation,
or, in the absence of local or state code, in the U.S. to the National Fuel Gas Code ANSI
Z233.1/NFPA 54 – latest edition, and in Canada, in accordance with NSCNGPI.
No. of Elbows Max. Straight Vent Length*
4 39' (11.7m)
3 45' (13.5m)
2 51' (15.3m)
1 57' (17.1m)
Pipe diameter 3" (75mm)
• Under normal conditions, this appliance will
not produce an exhaust flue temperature
in excess of 149°F (65°C) and schedule 40
PVC pipe may be used as the vent material.
If required by local code, schedule 40 or 80
CPVC may also be used on this appliance.
Refer to page 13 for additional requirements.
• Make sure the vent system is gas tight and
will not leak.
• Support the vent pipe with hangers at regular
intervals as specied by these instructions or
the instructions of the vent manufacturer.
• Do not common vent or connect more than
one appliance to this venting system.
•
The total vent length including horizontal & vertical
vent runs should be no less than 3' (0.9m).
• Do not store hazardous or ammable substances
near the vent termination and check that the
termination is not blocked in any way.
• Steam or condensed water may come out
from the vent termination. Select the location
for the termination so as to prevent injury or
property damage.
• If snow is expected to accumulate, take care
the end of the pipe is not covered with snow
or hit by falling lumps of snow.
General Requirements
Clearances
PVC or CPVC has been approved for use on this
appliance with zero clearance to combustibles.

12
Short length
Long length
**Table assumes straight vent pieces are 3’ (0.9m) each.
Shorter or longer vent pieces may also be used up to the
maximum allowed vent length.
* Do not change any other DIP switch.
* Vent length condition.
7
ON=OFF=
1
2
0
3
6
9
12
15
18
21
24
27
30
33
36
39
42
45
48
51
54
57
60
63
0.00
0.90
1.80
2.70
3.60
4.50
5.40
6.30
7.20
8.10
9.00
9.90
10.80
11.70
12.60
13.50
14.40
15.30
16.20
17.10
18.00
18.90
m 10 2 34ftVent length* Elbows
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
Number of
pieces**
1
10%
-3%
-3%
-5%
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
1
10%
-3%
-3%
-5%
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
1
10%
-3%
-3%
-5%
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
1
10%
-3%
-3%
-5%
1
1
1
2
2
2
2
2
2
2
2
2
2
2
1
10%
-3%
-3%
-5%
1
2
2
2
2
2
2
2
2
2
2
2
4” Pipe
1
2
The power must be unplugged when
adjusting the DIP switches to switch the
airow amount.
The unit can be adjusted to accommodate longer vent runs; refer to the below table to nd the
maximum vent length based on the number of elbows. Adjust the DIP switch according to the vent
condition noted in the tables below.
Note: By default, the unit has been set to the "short length" condition. When adjusting the DIP switch
for longer vent runs, the BTUH input of the appliance will be reduced by up to 5%.
Maximum Vent Length Adjustment DIP switch
- Two 90° elbows, maximum length = 18 ft. (5.4m)
(with DIP switches set at "short length" condition)
- Two 90° elbows, maximum length = 51 ft. (15.3m)
(with DIP switches set at "long length" condition)
[Maximum Vent Length Example]
• Disconnect power to the water heater before changing the DIP switch. Failure to perform
this
step will result in a "733" code displayed on the Display Window and a cease in operation .
If this occurs, disconnect, then reconnect power to the water heater to reset the system.
<Maximum Vent Length Congurations>

13
WARNING
CARBON MONOXIDE POISONING
Failure to properly seal the vent system could
cause flue products to enter the living space.
Item Material United States Canada
Exhaust Vent/Air Intake Schedule 40 PVC ANSI/ASTM D1785
ULC S636 Certified
Materials Only
PVC-DWV ANSI/ASTM D2665
Schedule 40 CPVC ANSI/ASTM F441
Pipe Cement/Primer PVC ANSI/ASTM D2564
CPVC ANSI/ASTM F493
Note: Do Not Use Cellular Foam Core Pipe
PVC/CPVC Installation Instructions
• Use only solid PVC or CPVC schedule 40 pipe. Cellular foam core piping is not allowed.
•
•
In Canada, plastic vent systems must be certified to ULC S636. The components of the certified
vent system must not be interchanged with other vent systems or unlisted pipe/fittings.
• In Canada, specified primers and glues of the ULC S636 certified vent system must be from a
single system manufacturer and not intermixed with other system manufacturer’s vent system
parts.
• Follow all general venting guidelines as outlined on this page.
• The pipe shall be installed so that the first 3’ (0.9m) of pipe from the appliance flue outlet is readily
accessible for visual inspection.
• When preparing and assembling the pipe, follow instructions as provided by the pipe
manufacturer. In general, the following practices must be observed:
o Squarely cut all pieces of pipe.
o Remove all burs and debris from joints and fittings.
o All joints must be properly cleaned, primed, and cemented. Use only cement and primer
approved for use with the pipe material as outlined in the above table.
•
• PVC or CPVC pipe has been approved for use on this appliance with zero clearance to combustibles.
All piping must be fully supported. Use pipe hangers at a minimum of 3’ (0.9m) intervals. Do not use
the water heater to support the vent piping.
3" schedule 80 pipe may also be used on this appliance, however the BTUH input of the
appliance will be reduced by up to 5%.
No. of Elbows
* Not including the termination
3
4
2
1
45' (13.5m)
39' (11.7m)
51' (15.3m)
57' (17.1m)
• Do not exceed the following maximum vent lengths:
Venting With PVC or CPVC
This appliance can be vented with non cellular core plastic pipe materials as specified in the below table.
Vent installations in Canada which utilize plastic vent systems must comply with ULC S636.
•
•Abird screen must be installed on the vent terminations to prevent debris or animals from entering the
piping. These screens are not supplied with the water heater and must be purchased separately
(part #VT3-PVCS, use part PVC or CPVC).
When attaching the piping to the water heater, use the appropriate primer and cement to ensure a
proper seal.
3" (75mm) Pipe*

14
Vent Pipe Installation
Horizontal Vent Termination- PVC/CPVC Materials Only
Intake and exhaust should face the same direction.
Intake and exhaust should keep the same
pressure zone.
2ft. Min
Interior View
Interior View Exterior View
Interior View Exterior View
1ft. Min1ft. Min
•
Insert the bird screen.
90° elbow vertical setting (downward).
•
Ensure at least 3ft (0.9m) or more distance between
the near edge of the air intake pipe or exhaust pipe
to the inside corner of a wall.
•
Ensure at least 2ft (0.6m) or more distance between
intake pipe and exhaust pipe.
The distance is measured at inside of pipe to inner
dimension.
•
Intake and exhaust should face the same direction.
Intake and exhaust should keep the same
pressure zone.
•
Insert the bird screen.
90° elbow vertical setting (downward).
•
Ensure at least 3ft (0.9m) or more distance between
edge of air intake pipe or exhaust pipe and corner wall.
•
Upper side is exhaust, lower side is intake.
The reverse connection is not allowed.
•
Ensure at least 1ft (0.3m) or more distance between
intake pipe and exhaust pipe.
The distance is measured at the outlets of
intake port (terminal) and exhaust port (terminal).
•
Intake and exhaust should face the same direction.
Intake and exhaust should keep the same
pressure zone.
•
Insert the bird screen.
90° elbow vertical setting (downward).
•
Ensure at least 3ft (0.9m) or more distance between
edge of air intake pipe or exhaust pipe and corner wall.
•
The side distant from wall is intake, the side near the
wall is exhaust.
The reverse connection is not allowed.
•
Ensure at least 1ft (0.3m) or more distance between
intake pipe and exhaust pipe.
The distance is measured at inside of pipe to inner
dimension.
•
•
Exhaust
Intake
Exhaust Intake
1ft. Min
Exterior View
Exhaust
Exhaust
Intake
Intake
Exhaust Intake
3” Min
WARNING
If the distance between the air inlet and exhaust vent terminations is too short, the water heater
will draw in the exhaust gases through the intake. There is a risk of inadequate combustion air
for the water heater, increasing Carbon Monoxide (CO) emissions and noise due to vibration.
•Termination elbows must be oriented vertically, pointing directly downward. Attempts to prevent
exhaust air from entering the air inlet by angling termination elbows in directions other than
directly downward will increase the risk of freezing.
•Reversing the air intake and exhaust pipes is not allowed.
Carbon Monoxide (CO) emissions and noise due to vibration will increase.
3” Min
3” Min
5.9”
5.9”
5.9”
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.

15
Vertical Vent Termination- PVC/CPVC Materials Only
•
•
•
•
•
•
•
•
Horizontal Vent Termination- PVC/CPVC Materials Only
•
•
•
•
•
•
•
•
Hanger
Straps
**1' mini
* Not supplied with water heater,
order separately.
mum recommended,
but not required.
3 ft. Min.
FirestopFirestop
Firestop/Support
Roof
Flashing
Roof
Flashing
Hanger
Strap
**1'
Minimum
**1'
Minimum
Support
Slope
Slope vent
Upwards
Intake
Exhaust
vent
Upwards
Intake Exhaust
12" over maximum
snow level
or 24", whichever
is greater.
12" over maximum
snow level
or 24", whichever
is greater.
Insert Bird
Screen* in
End of
90 Elbow
Storm
Collar
Storm
Collar
As illustrated on the left, make sure to keep a distance of 3' (0.9m)
or wider between the intake and exhaust when installing the vent piping.
The PVT-HL termination may be used in place of elbows as the
horizontal vent terminations. It is not necessary touse bird screens
with the PVT-HL termination.
Terminate at least 12" (300mm) above grade or above snow line.
Terminate at least 7' (2.1m) above a public walkway, 6' (1.8m)
from the combustion air intake of any appliance, and 3' (0.9m)
from any other building opening, gas utility meter, service regulator etc.
Terminate at least 3' (0.9m) above any forced air inlet within
10' (3m) , 1' (0.3m) below, 1' (0.3m) horizontallyfrom or 1' (0.3m)
above any door, window, or gravity air inlet into any building per
National Fuel Gas Code ANSI Z223.1/NFPA 54.
Slope the horizontal vent 1/4" upwards for every 12" (300mm)
toward the termination.
Use a condensation drain if necessary.
In the Commonwealth of Massachusetts a carbon monoxide detector
is required for all side wall horizontally vented gas fuel equipment.
Please refer to Technical Bulletin TB 010606 forfull installation
instructions.
As illustrated on the left, make sure to keep a distance
of 3' (0.9m) or wider between the intake and exhaust
when installing the vent piping.
Terminate at least 6' (1.8m) from the combustion air
intake of any appliance, and 3' (0.9m) from any other
building opening, gas utility meter, service regulator etc.
Enclose exterior vent systems below the roof line to limit
condensation and protect against mechanical failure.
When the vent penetrates a floor or ceiling and is not
running in a fire rated shaft, a firestop and support is
required.
When the vent termination is located not less than
8' (2.4m) from a vertical wall or similar obstruction,
terminate above the roof at least 2' (0.6m), but not
more than 6' (1.87m), in accordance with the National
Fuel Gas Code ANSI Z223.1/NFPA 54.
Provide vertical support every 3' (0.9m) or as required
by the vent pipe manufacturer's instructions.
A short horizontal section is recommended to prevent
debris from falling into the water heater.
When using a horizontal section, slope the horizontal
vent 1/4” upwards for every 12” (300mm) toward the
termination to drain condensate.
**1' minimum recommended,
but not required.
*
Not supplied with water heater,
order separately.
When choosing intake and exhaust terminations, you must use the
same type of elbow (i.e. both 90° elbows).
This will help with proper combustion by putting both terminations in
the same pressure zone.
When choosing intake and exhaust terminations, you must use the
same type of elbow (i.e. both 90° elbows).
This will help with proper combustion by putting both terminations in
the same pressure zone.
Insert Bird
Screen* in
End of
90 Elbow
Insert Bird Screen*
in End of 90 Elbow
3” Min.
Vent Pipe Installation
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.

16
•
•
•
•
•
•
•
Hanger
Intake*
Horizontal Vent Termination- 3" (75mm) Concentric PVC/CPVC Termination
Exhaust*
Straps
The concentric termination may be shortened,
but not lengthened from its original factory
supplied length.
The concentric termination may only be used
for horizontal terminations.
Terminate at least 12" (300mm) above grade or
above snow line.
Terminate at least 7' (2.1m) above a public walkway,
6' (1.8m) from the combustion air intake of any
appliance, and 3' (0.9m) from any other building
opening, gas utility meter, service regulator etc.
Terminate at least 3' (0.9m) above any forced air
inlet within 10' (3m), 1' (0.3m) below, 1' (0.3m)
horizontally from or 1' (0.3m) above any door,
window, or gravity air inlet into any building per
National Fuel Gas Code ANSI Z223.1/NFPA 54.
Slope the horizontal vent 1/4" upwards for every
12" (300mm).
Use a condensation drain if necessary.
In the Commonwealth of Massachusetts a carbon
monoxide detector is required for all side wall
horizontally vented gas fuel equipment.
Please refer to Technical Bulletin TB 010606 for full
installation instructions.
Slope vent
Upwards
* 4" (100mm) pipe requires the use of a reducing coupling
just prior to the termination.
1" (25mm) to
4" (100mm)
No. of Elbows
3
2
1
4
Insert Bird Screen ***
in End of Termination
•
There must be a 1" (25mm) to 4" (100mm) clearance
between the outside wall and the air intake section
of the termination as illustrated on the left.
•
•
3" (75mm) PVC or CPVC pipe may be used
with the concentric termination.
Maintain the same vent pipe diameter from the
water heater flue to the termination.
Do not exceed the maximum vent lengths as
specified in this section.
•
Install a securing strap to prevent movement of
the termination.
Strap
Max. Straight Vent Length**
Pipe diameter
3" (75mm)
** Not including the concentric termination.
45' (13.5m)
39' (11.7m)
51' (15.3m)
57' (17.1m)
*** Not supplied with
water heater,
order separately.
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.

17
Vertical Vent Termination- PVC/CPVC Materials Only
Firestop
Firestop/Support
Roof
Flashing
Storm
Collar
Hanger
Strap
Horizontal Vent Termination- PVC/CPVC Materials Only
Hanger
Straps
**1' (0.3m) Minimum
Slope vent
Upwards
**1' (0.3m) Minimum
* Not supplied with water
heater, order separately.
recommended, but not required.
Insert Bird
Screen* in
Each End
of Tee
Support
Insert Bird
Screen* in
End of 90
Elbow
Slope vent
Upwards
Pipe Material PVC or CPVC
* Not supplied with water
heater, order separately.
**1' (0.3m)
Minimum
**1' (0.3m) minimum
recommended, but not required.
•
•
•
•
•
•
•
•
•
•
•
•
•
•
A tee, the PVT-HL termination may be used for the
vent termination. It is not necessary to use bird
screens with the PVT-HL termination.
Terminate at least 12" (300mm) above grade or above
snow line.
Terminate at least 7' (2.1m) above a public walkway,
6' (1.8m) from the combustion air intake of any appliance,
and 3' (0.9m) from any other building opening, gas utility
meter, service regulator etc.
Terminate at least 3' (0.9m) above any forced air inlet within
10' (3m) , 4' (1.2m) below, 4' (1.2m) horizontallyfrom or
1' (0.3m) above any door, window, or gravity air inlet into any
building per National Fuel Gas Code ANSI Z223.1/NFPA 54.
Slope the horizontal vent 1/4" upwards for every 12" (300mm)
toward the termination.
Use a condensation drain if necessary.
In the Commonwealth of Massachusetts a carbon monoxide
detector is required for all side wall horizontally vented gas
fuel equipment.
Please refer to Technical Bulletin TB 010606 for full installation
in structions.
Terminate at least 6' (1.8m) from the combustion air
intake of any appliance, and 3' (0.9m) from any other
building opening, gas utility meter, service regulator etc.
Enclose exterior vent systems below the roof line to limit
condensation and protect against mechanical failure.
When the vent penetrates a floor or ceiling and is not
running in a fire rated shaft, a firestop and support is
required.
When the vent termination is located not less than
8' (2.4m) from a vertical wall or similar obstruction,
terminate above the roof at least 2' (0.6m), but not
more than 6' (1.87m), in accordance with the National
Fuel Gas Code ANSI Z223.1/NFPA 54.
Provide vertical support every 3' (0.9m) or as required
by the vent pipe manufacturer's instructions.
A short horizontal section is recommended to prevent
debris from falling into the water heater.
When using a horizontal section, slope the horizontal
vent 1/4” upwards for every 12” (300mm) toward the
termination to drain condensate.
Exhaust
Intake
Exhaust
Intake
90 Elbow
SV Conversion Kit
Accessory
(#SV-CK-3)
90 Elbow
SV Conversion Kit
Accessory
(#SV-CK-3)
Inlet screen
Inlet screen
3” Min.
No. of Elbows
3
2
1
4Max. Straight Vent Length***
Pipe diameter 3" (75mm)
*** Not including the termination.
45' (13.5m)
39' (11.7m)
51' (15.3m)
57' (17.1m)
Vent Pipe Installation (When supplying combustion air from the indoors (SV, non-direct vent))
• Disconnect power to the water heater before changing the DIP switch. Failure to perform this
step will result in a "733" code displayed on the Display Window and a cease in operation.
If this occurs, disconnect, then reconnect power to the water heater to reset the system.
• Dip switch 3 if combustion air will be supplied form the indoors as illustrated to the right.
• SV Conversion kit #SV-CK-3 is required for the air intake.
* Dip switch No.3 is turned on.
Failure to perform the above 2 steps could result in a re or explosion causing
property damage, personal injury or death.
Refer to the instructions provided with the conversion kit for additional details.
WARNING
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.

18
• Provide two permanent openings to allow cir-
culation of combustion air.
• Make each opening 180 square inches if they
provide indoor air, and 100 square inches for
outdoor air.
• If the unit is installed in a mechanical closet,
provide a 24" (600mm) clearance in front of
the unit to the door.
• If combustion air will be provided through a
duct, size the duct to provide 60 cubic feet of
fresh air per minute.
Supply combustion air to the units as per the National Fuel Gas Code, ANSI Z223.1
and in Canada, in accordance with CSA-B149.1.
Combustion Air
Openings supplying indoor air
9" (225mm)
20" (500mm)
9" (225mm)
20" (500mm)
▲The illustration is an example. Please check with the actual water heater about the position of piping, and form.

19
Follow the instructions from the gas supplier.
8. Gas Piping
Gas Type
The gas type indicated on the water heater rating plate (NG or LP) must match the type of gas being
supplied to the water heater.
Gas Conversions
If the gas type supplied does not match the gas type on the rating plate, contact your water heater supplier for
a replacement unit with the proper gas type. If a gas type conversion must be made, there are conversion
kits available for some models. [The conversion kit shall be installed by a qualied service agency in
accordance with the manufacturer’s instructions and all applicable codes and requirements of the
authority having jurisdiction. The qualied service agency is responsible for the proper installation of this
kit. Improper installation of this kit will void the warranty. Conversion kits will only be shipped directly to
the Distributor or Agency performing the conversion.]
Meter
The gas meter must be sized properly for the water heater and other gas appliances to operate properly.
Select a gas meter capable of supplying the entire btuh demand of all gas appliances in the building.
The guidelines and examples we have provided in this manual section are for reference only.
The sizing and installation of the gas system for this water heater, as with any gas appliance, is the
sole responsibility of the installer. The installer must be professionally trained to do such work and
must always follow all local and national codes and regulations. Gas line sizing calculations must
be performed for every installation. Please contact Noritz America at 866-766-7489 if you have
any questions or concerns.
CAUTION
Regulators
Ensure that all gas regulators used are operating properly and providing gas pressures within the specied
range of the water heater being installed. Excess gas inlet pressure may cause serious accidents.
CAUTION
Pressure
Check the gas supply pressure immediately upstream at a location provided by the gas company. Supplied
gas pressure must be within the limits shown in the specications section with all gas appliances operating.
The inlet gas pressure must be within the range specied. This is for the purposes of input adjustment. Low
gas pressure may cause a loss of ame or ignition failure at other appliances in the home, which may result
in unburned gas in the home. Serious accidents such as re or explosion may result.
Measuring Gas Pressure
In order to check the gas supply pressure to the unit, a tap is provided on the gas
inlet. Remove the 9/32” hex head/Philips screw from the tap, and connect a
manometer using a silicon tube. Open up at least 2 xtures and hold in the maximum
manifold pressure button on the circuit board. Please call Noritz for details..
WARNING

20
Pressure Test
The appliance and its gas connections must be leak tested before placing the appliance in operation.
The appliance must be isolated from the gas supply piping system by closing its individual manual
shutoff valve during any pressure testing of the gas supply piping system at test pressures equal to
or less than ½ psig (3.5 kPa). We do not recommend pressure testing in excess of ½ psig (3.5kPa).
If it must be done, the appliance and its individual shutoff valve must be completely disconnected
from the gas supply piping system during the test process.
Pipe Sizing/Flexible Connectors
A gas shutoff valve must be installed on the supply line. Gas ex lines are not recommended unless
the minimum inside diameter is ¾” or greater and the rated capacity of the connector is equal to
or greater than the BTU capacity of the water heater. Gas piping shall be in accordance with local
utility company requirements and/or in the absence of local codes, use the latest edition of National
Fuel Gas Code (NFPA54GC), ANSI Z223.1. In Canada, use the latest edition of CSA B149.1, National
Gas and Propane installation code. Size the gas line according to total btuh demand of the building
and length from the meter or regulator so that the following supply pressures are available even at
maximum demand.
WARNING
Natural Gas Supply Pressure
Min 4” WC
Max 10.5” WC
LP Gas Supply Pressure
Min 8” WC
Max 14” WC
Reference Tools & Sample Calculations
The tables and samples below are for reference only. The professional sizing and installing the gas
line should always run the appropriate calculations before all installations.
CAUTION
Which Table to Use
• For NG installations with the initial supply pressure at point of delivery (at the meter, for example) is
less than 8” WC, use the 0.5” WC pressure drop table (Table 1).
• For NG installations with the initial supply pressure at point of delivery is greater than or equal to 8”
WC, use the 3.0” pressure drop table (Table 2).
• For all LP installation use (Table 3)
The inlet pressure must be at least 5” WC for NG or 8” WC for LP for all appliances in the gas system.
If the inlet gas pressure drops below 5” WC for NG or 8” WC for LP, the heater may continue to operate,
but the other appliances in the house may experience ame loss or ignition failure, which can result in
gas leakage into the home. Refer to the NFPA 54 for details.
Please contact Noritz for details. For corrugated stainless steel tubing (CSST) capacity tables, please
consult with the manufacturer.