Noritz proTOUGH NR981-DVC 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 fire or explosion may result
causing property damage, personal injury or death.
NORITZ AMERICA
CORPORATION
Installation Manual
TANKLESS GAS WATER HEATER
NR981-DVC (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
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 fill in all of the required
items on the warranty and to hand the warranty to the customer along with the Owner's Guide.
CAUTION
SBA8871-2
Rev. 03/13
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 Propane Installation Code (NSCNGPIC).
Noritz America reserves the right to discontinue, or change at any
time, the designs and/or specifications of its products without notice.
Low NOx
Approved by
SCAQMD
14 ng/J or 20 ppm
(Natural Gas Only)
CERTIFIED
R
*SBA8871*

2
1.
Included Accessories
The following accessories are included with the unit.
Check for any missing items before starting installation.
Q’ty
ShapePart
Anchoring Screw 1
each
Part Shape Q’ty
5
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
QuickConnect Cord
(QC-2) 1
1
IsolationValves
(includes pressure
reliefvalve)
Owner's Guide, Warranty,
Installation Manual
(this document)
Part No. Description
4"-CVP-4STR
12"-CVP-12STR
24"-CVP-24STR
36"-CVP-36STR
Adjustable
Part No. Description
CVT-S
Flange
Adapter
HorizontalTermination
FlangeElbow
Part No. Description
CRCAI-1
90 Elbow
Adjustable
90 Elbow
Support Strap
CVP-45ELB
CSCR-1
StandardHorizontalKit
FP-5-OUT
RoofFlashing
(0-45 )
Straight Straight
Termination
11"-CVP-11ADJ
16"-CVP-16ADJ
40"-CVP-40ADJ
Rain Cap with Air Intake
CWF
StormCollarRing
CVP-90ELB SS5-2
CARF-1
45 Elbow Plate
CVP-90ADJELB
CWF-90ELB HorizontalKit - CVK-H
Vertical Kit -CVK-V
Note: Additional vent pieces are available; consult the latest product catalogue for details.
Remote Controller
(RC-9018M) 1

3
G
Quick Connect
Cord
Gas Supply Piping
Cold Water Supply
Hot Water
Operation panel
*1
Cord
Connector Cord Connector
3.
Quick Connect Multi System Installation
• The Quick Connect Multi System allows the installation of two units together utilizing only the Quick
Connect Cord.
The Quick Connect Cord is 6' (2m) long. Install the units 2-18" (50-457mm) apart from each other
to ensure the cord will be able to reach between the units. (See Typical Plumbing diagram).
(If the distance between the two units is too great, not only will the cord not be able to reach,
but the water temperature may also become unstable because of the difference in pipe length
between the two units).
*1 When connecting two units, disconnect
the operation panel connector from
the other unit.
Note: Connect the operation
panel to only one of
the units.
System Diagram
• Insulate the hot water piping to prevent heat loss. Insulate and apply heating materials to the
cold water supply piping to prevent heat loss and freezing of pipes when exposed to exces-
sively cold temperatures.
Leave enough clearance around the plumbing
to apply insulation. It will be necessary to add
bends to the piping to ensure that this
clearance is available.
Size the piping to allow for the
maximum flow rates of the units.
Distance at center: 16-32" (406-812mm).
Union
Hot Water
Shutoff
Valve
Cold Water
Distance on sides
2-18" (50-457mm).
Make this distance as short as possible.
* The hot water temperature will
become unstable as the pipe
length increases.
Union
Quick Connect
Cord
Pressure
Relief
Valve Shutoff
Valve
Union
Gas
Valve
Shutoff Valve
The backflow preventer is
put up before it diverges.
Typical Plumbing

4
4. Before Installation
Checkup
• Check the fixing brackets and vent pipe yearly for damage or wear. Replace if necessary.
DANGER
Do Not Use Equipment for Purposes Other Than Those Specified
• Do not use for other than increasing the temperature of the water supply, as unexpected accidents
mayoccur as a result.
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
Check the Gas
• Check that the rating plate indicates the
correct type of gas.
• Check that the gas supply line is sized for
199,900Btuh for this unit.
Check the Power
• The power supply required is 120VAC, at 60Hz.
May result in fire 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. Do not use a solar pre-heater with the quick-connect multi-system.
Precautions on Vent Pipe
• This appliance requires the use of special concentric type vent pipe specified by Noritz America.
Do not attempt to use materials that are not specified for use on this appliance.
Improper venting may result in a fire, 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 termi-
nationfrom blockage by snowdriftsor damage from snowfalling offofroofs.

5
5. 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 floors 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 flow.
• 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 fires 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 fire 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 fire 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.
Theheat and moisture fromthe water heater maycausediscoloration of
wallsand resinous materials, orcorrosion of aluminum materials.
Prohibited
DANGER
WARNING
CAUTION
Prohibited

6
• 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 flow 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 flue termination will
have the proper clearances according to the National Fuel Gas
Code(ANSI Z223.1).
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 re-
quest 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 or phone numbers listed below:
Noritz N-Vent www.noritz.com

7
6. 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
8" (200mm)
or more
Distance from
the side
12" (300mm)
or more
2" (50mm)
or more
3" (75mm) or more
3" (75mm) or more
4" (100mm)
or more
8" (200mm)
or more

8
7. Installation
Securing to the wall
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.
DescriptionRef
A=
Clearance above grade, veranda, porch,
deck, or balcony
B=
Clearance to window or door that may
be opened
C=
Clearance to permanently closed window
D=
Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet (61 cm)
from the center line of the terminal *
E=
Clearance to unventilated soffit *
F=
Clearance to outside corner *
G=
Clearance to inside corner *
H=
Clearance to each side of center line
extended above meter/regulator assembly
3 ft (91 cm) within a height
15 ft (4.5 m) above the
meter/regulator assembly
I=
Clearance to service regulator vent outlet 3 ft (91 cm)
J=
Clearance to nonmechanical air supply
inlet to building or the combustion air inlet
to any other appliance
K=
Clearance to a mechanical air supply inlet 6 ft (1.83 m)
L=
Clearance above paved sidewalk or paved
driveway located on public property
Clearance under veranda, porch, deck,
or balcony
7 ft (2.13 m)†
M=
1
In accordance with the current CSA B149.1 Natural Gas and Propane Installation Code
2
In accordance with the current ANSI Z223.1 / NFPA 54 National Fuel Gas Code
† 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.
* Clearance in accordance with local installation codes and the requirements of the gas supplier.
Clearance to opposite wall is 24 inches (60 cm).
12 in (30 cm)‡
*
12 in (30 cm)
36 in (91 cm)
*
*
*
*
*
*
*
*
3 ft (91 cm) above if within
10 ft (3 m) horizontally
*
12 in (30 cm)
12 in (30 cm)
12 in (30 cm)
36 in (91 cm)
US Direct Vent
Installations 2
Canadian Direct Vent
Installations 1
Vent Terminal
D
E
B
B
F
B
A
G
H
I
CB
M
K
J
B
B
L
Air Supply Inlet
Area Where Terminal
is Not Permitted
A

9
IllustrationCheck
6. Drill holes for the remaining four screws.
7. Hang the unit again by the first screw, and then
insert and tighten the remaining four screws.
8. Take waterproofing 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.
• The distance between the unit and the wall can be
adjusted within the range of 0.4 - 1.8" (10 - 46mm).
Adjust the brackets as necessary to accommodate
the vent system (factory default is 0.4" (10mm)).
1. Loosen the four screws in the mounting bracket (upper),
match the desired mark to the back of the unit, and
then tighten the screws.
2. Loosen the four screws in the mounting bracket (lower) and
secure it in the same position as the upper mounting bracket.
3. Drill a single screw hole, making sure to hit a stud.
4. Insert and tighten the screw and hang the unit by
the upper wall mounting bracket.
5. 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 suffi-
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 inflict injury.
• Be careful not to hit electrical wiring, gas, or water
piping while drilling holes.
Item
CAUTION
Be sure to do
Mounting Bracket
(upper)
Anchoring Screw
Location of Screw Hole
Locating Screw Holes
Installations at Elevations
Above 2,000 ft.(610m).
• 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 "73" code displayed on the operation panel
and a cease in operation. If this occurs, disconnect,
then reconnect power to the water heater to reset the
system.
Note : Please refer to page 21 for the location of the
dip switch bank.
0.4 - 1.8"
(10 - 46mm)
mounting bracket
(upper)
mounting bracket
(lower)
mark
(0.4" (10mm) intervals)
Do not chan e an other di s itches.
Hi h elevation ad ustment.
6
2 001 - 4 000 ft (611 - 1 220m)
0 - 2 000 ft (0 - 610m)
4 001 - 6 000 ft (1 221 - 1 830m)
6 001 - 8 000 ft (1 831 - 2 440m)

10
> 3" (75mm)
(20-75mm)
0.8"-3"
< 0.8"
(20mm)
Straight Termination Installation Precautions.
Note the following vent terminal installation requirements.
• Do not install the vent terminal indoors
• Install the vent terminal with a downward slope
upward
slope
downward
slope
•Install with the proper length protruding through the wall •Avoid storing hazardous
objects near the terminal
Gasoline
Gas
Proper installation.
The red line can be
seen, but not more
than 2.2" (55mm)
from the wall.
Vent terminal
Vent terminal
not far
enough too far
Snow
drift Tree
•Avoid installing the terminal where obstacles
will block it
•
Do not cover the vent terminal with any type of protective
screen or enclosure. Blocked terminals can cause abnor-
mal combustion resulting in undesired performance from
the water heater.
8. Vent Pipe Installation
• This appliance requires the use of special concentric type vent pipe specified by Noritz America.
Do not attempt to use materials that are not specified for use on this appliance.
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.
• Clearance from vent terminal.
If multiple units are installed, the concentric vent terminals must be separated
by a minimum of either 12" (300mm) horizontally or 60" (1.5m) vertically.
Vent terminal Vent terminal
12" (300mm) or more
60" (1.5m) or more

11
The power must be unplugged when
adjusting the dip switches to switch
the airflow amount.
The unit can be adjusted to accommodate longer vent runs; refer to the below table to find the
maximum vent length based on the number of elbows. Adjust the dip switches according to the vent
condition noted in the tables below.
Note: By default, the unit has been set to the "minimum length" condition. When adjusting the dip
switches for longer vent runs, the BTUH input of the appliance will be reduced by up to 8%.
Maximum Vent Length Adjustment Dip Switches
- One 90 elbow, maximum length = 3 ft (0.9m)
(with dip switches set at "minimum length" condition)
- Two 90 elbows, maximum length = 30 ft (9.0m)
(with dip switches set at "maximum length" condition)
[Maximum Vent Length Example]
• Disconnect power to the water heater before changing the dip switches. Failure to perform
this step will result in a "73" code displayed on the operation panel and a cease in operation . If
this occurs, disconnect, then reconnect power to the water heater to reset the system.
Note : Please refer to page 21 for the location of the dip switch bank.
3
6
12
1
18
21
24
2
30
32
3
38
41
0. 0
1.80
2. 0
3.60
4. 0
.40
6.30
.20
8.10
.00
.0
10.80
11. 0
12.60
m102346ft Vent len th l o s
1
2
3
4
6
8
10
11
12
13
14
um er of
ieces 11
1
12
2
2
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
4
44
4
4
2
2
**Table assumes straight vent pieces are (0. m) each.
Shorter or longer vent pieces ma also be used up to the ma imum allowed vent length.
2
2
2
1 Minimum length
2
4
Short length
ong length
Ma imum length
<Maximum Vent Length Configurations>
* Do not change an other dipswitches.
* Vent length condition.
1 Minimum length
78
2 Short length
ong length
4 Ma imum length

12
Horizontal Vent 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 me-
ter, service regulator etc.
• T
erminate 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" (6mm)
downwards for every 12" (300mm) towards
the termination.
•
The integrated condensate collector must be
used for vertical runs in excess of 3' (0.9m).
Remove the cap from the collector prior to at-
taching the drain line.
• In the Commonwealth of Massachusetts a car-
bon monoxide detector is required for all side
wall horizontally vented gas fuel equipment.
Please refer to Technical Bulletin TB 010606
for full installation instructions.
lo
Han er
Stra s
lan e
da ter
late
ermination
3 (0. m) a .
Slo e vent
Do n ards
Condensate collector
must e used if the
vertical run e ceeds
3 (0. m).
Drain condensate
accordin to
local codes.
• Connect the vent pipe firmly so that it will pre-
vent exhaust gases from leaking.
• Steam or condensed water may drip out of the
vent terminal. Dispose of this condensed water
according to local codes and in order to prevent
injury or property damage.
• If this product will be installed in an area where
snow is known to accumulate,protect the vent
termination from blockage by snow drifts or
damage from snow falling off of roofs.
• Support the vent pipe with hangers at a mini-
mum of every 7' (2.1m).
• Make the vertical pipe as short as possible.
• Do not common vent or connect more than
one appliance to this venting system.
•
Terminate at least 12" (300mm) above grade or
snow line.
• Terminate at least 7' (2.1m) above a public
walkway.
• Exceeding the maximum vent length is danger-
ous and may result in bad combustion.
•
Install the vent terminal so that all exhaust is di-
rected to and all intake air is taken from outdoors.
• Do not store hazardous or flammable substanc-
es near the vent terminal.
•
Slope the vent pipe 1/4" (6mm) for every 12"
(300mm) either towards the horizontal termination
or towards the integrated condensate collector.
When using the condensate collector, create a
trap in the drain line and pre-charge it with wa-
ter to prevent exhaust gas leakage.
• Maintain the same vent pipe diameter all the
way to the end.
• Noritz Concentric vent pipe is approved for use
on this appliance with zero clearance to com-
bustibles.
• Use only Noritz specified venting products.
WARNING
Be sure to do
CARBON MONOXIDE POISONING
Do not remove the cap from the condensate collector unless it is being used to drain
condensate. Without the cap in place, flue products could enter the living space.

13
(Combustible material)
External wall,
combustible material
• Inspection openings are suggested for the vent intake and exhaust
pipes if they are installed in an enclosure. These openings should
be near the entrance and exit of the vent into the enclosure.
• These openings should be 18" x 18" (450mm x 450mm).
Suggested inspection openings
18" x 18" (450mm x 450mm)
When the vent pipe passes through an enclosed space:
Ceiling
Sloping down toward vent terminal
Vertical Vent Termination
iresto
iresto
Su ort
oof lashin
( ase and da ter)
ir nta e
ie
ain
Ca
(1. m) or more
Han er
Stra
lo
Slo e vent
U ards
Condensate collector
must e used if the
vertical run e ceeds 3 (0. m).
Drain condensate
accordin to
local codes.
• Terminate at least 6' (1.8m) from the combus-
tion air intake of any appliance, and 3' (0.9m)
from any other building opening, gas utility me-
ter, 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 obstruc-
tion, terminate above the roof at least 2' (0.6m),
but not more than 6' (1.8m), in accordance
with the National Fuel Gas Code ANSI Z223.1/
NFPA 54.
• Provide vertical support every 7' (2.1m).
• Slope the horizontal vent 1/4" for every
12" (300mm) towards the drain tee.
• The integrated condensate collector must be
used for vertical runs in excess of 3' (0.9m).
Remove the cap prior to attaching the drain
tubing.
• When 2 units are installed in a Quick Connect
Multi System, maintain a minimum distance of
5' (1.5m) between the vertical terminations.

14
Gas Meter
Select a as meter ca a le of su l in the entire
tuh demand of all as a liances in the uildin .
Gas Connection
Do not use i in ith a diameter smaller than
the inlet diameter of the ater heater.
as fle lines are not recommended unless
the are rated for 1 00 tuh.
nstall a as shutoff valve on the su l line.
Use onl a roved as i in materials.
ollo the instructions from the as su lier.
Gas Pressure
Si e the as line accordin to total tuh demand
of the uildin and len th from the meter or
re ulator so that the follo in su l ressures
are availa le even at ma imum demand:
atural as Su l ressure
in. 4" WC
a . 10. " WC
as Su l ressure
in. 8" WC
a . 14" WC
9. Gas Piping
he a liance and its individual shutoff valve must e disconnected from the as su l i in s stem
durin an ressure testin of that s stem at test ressures in e cess of 1⁄2si (3. a).
he liance must e isolated from the as su l i in s stem closin its individual manual
shutoff valve durin an ressure testin of the as su l i in s stem at test ressures e ual to or
less than 1⁄2si (3. a).
he a liance and its as connections must e lea tested efore lacin the a liance in o eration.
The inlet gas pressure must be within the range specified. This is for the purposes of input adjustment.
n order to choose the ro er si e for the as line consult local codes or the ational uel as Code
S 223.1.
atural as
eter See ne t a e for the i e ca acit charts.
orit an less as Water Heater
(1 00 tuh)
Clothes Dr er
(3 000 tuh)
ar ecue
( 0 000 tuh)
as an e Stove
(6 000 tuh)
10 (3m)
10 (3m)
10 (3m)
10 (3m)
(1. m)
(1. m)
(1. m)
(1. m)
as ire lace
(2 000 tuh)
Instructions
1. Si e each outlet ranch startin from the furthest
usin the tuh re uired and the len th from the
meter.
2. Si e each section of the main line usin the
len th to the furthest outlet and the tuh
re uired ever thin after that section.
Sample Gas Line
Sample Calculation
utlet : 4 (13. m) (Use 0 (1 m)) 0 000 tuh re uires 1 2"
utlet : 40 (12m) 6 000 tuh re uires 1 2"
Section 1: 4 (13. m) (Use 0 (1 m)) 11 000 tuh re uires 3 4"
utlet C: 30 ( m) 3 000 tuh re uires 1 2"
Section 2: 4 (13. m) (Use 0 (1 m)) 1 0 000 tuh re uires 3 4"
utlet D: 2 ( . m) (Use 30 ( m)) 2 000 tuh re uires 1 2"
Section 3: 4 (13. m) (Use 0 (1 m)) 1 000 tuh re uires 1"
utlet : 2 ( . m) (Use 30 ( m)) 1 00 tuh re uires 3 4"
Section 4: 4 (13. m) (Use 0 (1 m)) 3 4 00 tuh re uires 1-1 4"
Section 3 Section 2 Section 1
utlet
utlet
utlet C
utlet D
utlet
(1. m)(1. m)
Section 4
Measuring Gas Pressure
n order to chec the as su l ressure to the unit a
ta is rovided on the as inlet. emove the he head
hili s scre from the ta and connect a manometer
usin a silicon tu e.
n order to chec the as manifold ressure a air of
ta s are rovided on the as valve inside the unit.
he ressure can e chec ed either removin the he
head hili s scre and connectin a manometer ith a
silicon tu e or removin the 1 8" scre ith an
allen rench and connectin the a ro riate ressure
au e.

1
a imum atural as Deliver Ca acit in Cu ic eet er Hour (0.60 S ecific ravit 0. " WC ressure Dro )
Contact the as Su lier for tu Cu ic t. of the Su lied as. 1000 U Cu ic t. is a ical Value
a imum i uefied etroleum (Undiluted) Deliver Ca acit in housands of tuh (0. " WC ressure Dro )
en th in eet
en th in eet
ie
Si e
ie
Si e
12"
12"
34"
34"
1"
1"
1 1 4"
1 1 4"
1 1 2"
1 1 2"
2"
2"
2 1 2"
3"
3 1 2"
4"
10 (3m) 20 (6m) 30 ( m)
40 (12m) 0 (1 m) 60 (18m) 0 (21m) 80 (24m) 0 (2 m) 100 (30m) 12 (3 . m)
10 (3m) 20 (6m) 30 ( m) 40 (12m) 0 (1 m) 60 (18m) 0 (21m) 80 (24m) 0 (2 m) 100 (30m) 1 0 (4 m) 200 (60m)
10 (3m) 20 (6m) 30 ( m) 40 (12m) 0 (1 m) 60 (18m) 0 (21m) 80 (24m) 0 (2 m) 100 (30m) 1 0 (4 m) 200 (60m)
10 (3m) 20 (6m) 30 ( m) 40 (12m) 0 (1 m) 60 (18m) 0 (21m) 80 (24m) 0 (2 m) 100 (30m) 1 0 (4 m) 200 (60m)
12 (3 . m)
14
363
684
1404
2103
40 0
64
11 412
16 0
23 2
11
24
40
6
144
284
443
843
11 484
18
6
200
3
1161
223
363
62
222
12 84
da ted from U C 1
82
11
323
663
3
113
304
31
83
10
3
12
286
88
880
16 6
203
48
64
66
138
232
8
136
244
432
6338
8830
61
12
23
40
34
1413
22 3
383
831
8123
63044
118 111 104 3
222 208 1 1 4
46
683
131
20 6
30
42
428
641
1234
166
34 6
00
01
404
60
116
18
3284
4808
66 8
38
36
1033
1646
210
4261
36
26
10 1
220
330
6221
18
33
32
14 6
22
4331
12
310
1212
18 8
346
12
26
04
103
1
22
114
23
448
13
141
2646
103
21
40
834
12
23 4
6
16
38
1
1181
220
8
18
346
24
1086
204
83
13
322
6
1023
121
8
162
30
630
6
1811
6
146
26
866
1606
63
132
22
11
8
14 6
112
213
440
6
1260
a imum Ca acit of le rac i e in Cu ic eet er Hour of Natural Gas (0.60 S ecific ravit 0. " WC ressure Dro )
en th in eet
ie
Si e
34"
1"
1 1 4"
1 1 2"
2"
206
383
614
1261
234
14
26
418
888
20 8
121
218
334
23
16 8
10
188
284
62
14 2
4
168
21
131
86
13
22
0
1203
80
141
20
41
1114
132
14
440
1042
1
12
181
41
83
6
118
11
33
33
4
13
320
62
48
82
116
2
661
a imum Ca acit of le rac i e in housands of tuh Liquefied Petroleum ( 0. " WC ressure Dro )
en th in eet
ie
Si e
34"
1"
1 1 4"
1 1 2"
2"
32
601
13
4638
232
42
661
1404
328
11
344
28
1143
2684
166
2
44
88
232
14
26
3
884
2082
136
241
3
80
102
126
222
330
4
161
118
208
30
66
164
112
1
286
66
14
106
186
20
621
14
8
143
21
06
120
6
12
183
438
104
or reference onl . lease consult as i e manufacturer for actual i e ca acities.
or reference onl . lease consult as i e manufacturer for actual i e ca acities.
a imum Ca acit for as le Connectors in Cu ic eet er Hour of Natural Gas (0.60 S ecific ravit 0. " WC ressure Dro )
en th in nches
ie
Si e
12"
34"
1"
1 1 4"
12" (300mm) 24" (600mm) 36" ( 00mm) 48" (1200mm) 60" (1 00mm) 2" (1800mm)
12" (300mm) 24" (600mm) 36" ( 00mm) 48" (1200mm) 60" (1 00mm) 2" (1800mm)
180 1 0
20
81
14 0
12
212
1200
106
21
442
1130
3
1
360
86
13
34
30
en th in nches
ie
Si e
12"
34"
1"
1 1 4"
288 240
46
30
23 2
200
40
82
120
16
344
08
1808
14
31
638
136
13
28
6
1488
a imum Ca acit for as le Connectors in housands of tuh Liquefied Petroleum ( 0. " WC ressure Dro )
or reference onl . lease consult as i e manufacturer for actual i e ca acities.
rac i e is a re istered trademar of me a le .
as ine Si in for a orit an less as Water Heater

16
10.
Water Piping
his a liance is suita le for com ination ota le ater and s ace heatin a lications. t cannot e used for s ace
heating applications only. Do not use this appliance if any part has been underwater. Immediately call a qualified
service technician to ins ect the a liance and re lace an art of the control s stem and as control hich has
een under ater.
If the water heater is installed in a closed water supply system, such as one having a backflow preventer in the
cold ater su l line means shall e rovided to control thermal e ansion. Contact the ater su lier or a local
lum in ins ector on ho to control this situation.
ressure relief valve must e installed near the hot ater outlet that is rated in accordance ith and com l in
ith either he Standard for elief Valves and utomatic Shutoff Devices for Hot Water Su l S stems S
21.22 or he S S oiler and ressure Vessel Code Section V (Heatin oilers). his ressure relief
valve must e ca a le of an hourl tu rated tem erature steam dischar e of 1 00 tuh. ulti le valves ma e
used. he ressure relief ca acit must not e ceed 1 0 si . o valve shall e laced et een the relief valve and
the ater heater. he relief valve must e installed such that the dischar e ill e conducted to a suita le lace for
dis osal hen relief occurs. o reducin cou lin or other restriction ma e installed in the dischar e line. he
dischar e line must e installed to allo com lete draina e of oth the valve and the line. f this unit is installed ith
a se arate stora e vessel the se arate vessel must have its o n tem erature and ressure relief valve. his valve
must also com l ith he Standard for elief Valves and utomatic as Shutoff Devices for Hot Water Su l
S stems S 21.22. (in the U.S. onl ). tem erature relief valve is not re uired ut if one is used do not install
the valve with the probe directly in the flow of water. This may cause unwarranted discharge of the valve.
i in and com onents connected to the ater heater shall e suita le for use ith ota le ater.
o ic chemicals such as those used for oiler treatment shall not e introduced into the ota le ater.
ater heater used to su l ota le ater ma not e connected to an heatin s stem or com onents
reviousl used ith a non ota le ater heatin a liance.
When ater is re uired in one art of the s stem at a hi her tem erature than in the rest of the s stem means
such as a mi in valve shall e installed to tem er the ater to reduce the scald ha ard.
Installation and service must be performed by a qualified plumber. In the
Common ealth of assachusetts this roduct must e installed a licensed
plumber or gas fitter in accordance with the Massachusetts Plumbing and Fuel
as Code 248 C Sections 2.00 and .00. serve all a lica le codes.
lush ater throu h the i e to clean out metal o der sand and dirt efore connectin it.
erform the follo in insulation measures for revention of free in .
- a e a ro riate heat insulation measures (e. . ra in ith heat
insulation materials usin electric heaters) accordin to the climate
of the re ion to revent the i e from free in .
- a e sure that there are no ater lea s from the cold and hot ater
su l i es then insulate the i es com letel .
- e sure to also com letel insulate the ater su l valve and the
cold and hot water connections on the water heater (refer to the fig-
ure on the ri ht).
- Do not cover the ater drain lu ith insulation so that ater in the
pipe can be drained. (Refer to the figure in the right.)
Use a union coupling or flexible pipe for connecting the pipes to reduce the force applied to the piping.
Do not use i in ith a diameter smaller than the cou lin .
When feed ater ressure is too hi h insert a de ressuri in valve or ta e ater hammer revention measure.
• Avoid using joints as much as possible to keep the piping simple.
void i in in hich an air holdu can occur.
f installin the unit on a roof:
out lo er-level hot ater su l
f the unit is installed on a roof to su l ater to the levels elo ma e sure that the ater ressure su lied
to the unit does not dro elo 2 si. t ma e necessar to install a um s stem to ensure that the ater
ressure is maintained at this level.
Chec the ressure efore uttin the unit into o eration.
ailure to su l the ro er ressure to the unit ma result in nois o eration shorter lifetime of the unit and
ma cause the unit to shut do n fre uentl .
Com letel insulate
the ater inlet and
outlet fittin s.
nsulate the ater
su l valve com letel .
Do not cover the ater
drain lu ith insulation
so that ater in the i e
can e drained.

1
Supply water piping
Do not use VC iron or an i in hich has een
treated ith chromates oiler seal or other chemicals.
ount a chec valve and a shut off valve (near the inlet).
n order for the client to use the ater heater
comforta l 8.1 to 4 1 a (14 to 0 S ) of
ressure is needed from the ater su l .
e sure to chec the ater ressure. f the
ater ressure is lo the ater heater cannot
erform to its full ca a ilit and ma ecome a
source of trou le for the client.
Drain piping
ansion ater ma dro from the ressure
relief valve and wet the floor.
f necessar rovide drain i in or use a drain
hose to remove the ater.
Hot water piping
Do not use lead VC iron or an i in hich
has een treated ith chromates oiler seal or
other chemicals.
he lon er the i in the reater the heat loss.
r to ma e the i in as short as ossi le.
Use mi in valves ith lo ater resistance.
Use sho er heads ith lo ressure loss.
f necessar use a um or other means to
ensure that the su l ater ressure to the
inlet of the heater does not fall elo 2 S
hen the ma imum amount of ater is ein
demanded. lso install a ressure meter on
the inlet. f this is not done local oilin ill
occur inside the ater heater causin a normal
sounds and decreasin the dura ilit of the heat
e chan er.
Freeze Prevention
ree in is revented ithin the device automaticall unless the outside tem erature ithout ind
is elo -30 (-3 C).
When com ustion air is su lied from the indoors the room tem erature must e reater than 32 (0 C)
to revent free in and the room inside must not have ne ative ressure.
f this model is installed in an area here the outside tem erature can a roach free in conditions
of -30 (-3 C) or elo then additional free e rotection measures must e used. or tem orar
free e rotection measures refer to the ners uide.
he free e revention heaters ill not revent the lum in e ternal to the unit from free in .
rotect this lum in ith insulation heat ta e or electric heaters solenoids or i e covers.
n order for the free e revention heaters to o erate the ater heater must have o er at all times.

18
Water Treatment
ater Treatment S stem
Cit ater Suppl
Pressure
Relief
Valve
ot ater to i tures
Shutoff Valve
Drain
Cold to ater
eater
ptional Sediment
ilter
ater Treatment Device
Shutoff Valve
T pe of ater
ardness
evel Treatment Device lush re uenc *
T pe of ater
ardness
evel Treatment Device lush re uenc *
Soft
0-1 gpg
1- gpg
(0-17 mg )
one one one
one
one
one
Slightl ard
(17-51 mg )
one one
Moderatel
ard
ard
-7 gpg
(51-120 mg )
2 low or
ScaleShield
2 low or
ScaleShield
nce a ear** nce a ear
Twice a ear
nce a ear**
7-10 gpg
(120-171 mg )
Ver ard
10-14 gpg
(171-2 mg )
2 low
2 low
2 low
2 low
2 low
2 low
Treatment
Re uired
tremel
ard
Soft
Slightl ard
Moderatel
ard
ard
Ver ard
tremel
ard
14 gpg
( 2 mg )
0-1 gpg
1- gpg
(0-17 mg )
(17-51 mg )
-7 gpg
(51-120 mg )
7-10 gpg
(120-171 mg )
10-14 gpg
(171-2 mg )
14 gpg
( 2 mg )
Treatment
Re uired
Treatment
Re uired
Treatment
Re uired
* nstall orit solation Valves to allow for flushing.
** lushing is re uired if a water treatment device is not installed.
Suggested
Suggested
**
**
* nstall orit solation Valves to allow for flushing.
** lushing is re uired if a water treatment device is not installed.
Residential Use Treatment Guidelines Commercial Use Treatment Guidelines
RT
Tankless Gas
ater eater
f this ater heater ill e installed in an a lication here the su l ater is hard the ater must
e treated ith either the orit H2 lo or ScaleShield or a ater softener. efer to the elo ta les
for su ested treatment and maintenance measures to e ta en ased on the ater hardness level.
Dama e to the ater heater as a result of ater in e cess of 12 (200 m ) of hardness is not
covered the orit merica imited Warrant .
Note: Water softeners may be regulated by the local water jurisdiction, consult with the manufacturer
for code si in and installation
uidelines the elo dia ram is for reference onl . or more
information a out H2 lo and ScaleShield contact orit merica at 866- 66- 48 .

1
Recirculation S stem
Combination Potable ater and Space eating S stem
Cold ater Suppl
solation
it(*4)
Gas Suppl
uastat(* )
Pump Control Signal(*2)
Rela for Pump
(if larger than 85 atts)
ot ater
ptional 8-10 Gallon
Storage Tank
(To alleviate cold water sandwich)
Globe
Valve
Pump(*1)
pansion Tank
( nstall according
to local code)
i tures
ot ater Return
R
Pump
120V C
105
eutral
Ground
ive
S
solation
it(*1)
Gas Suppl ackflow Preventer
(optional)
Check
Valve(* )
Cold ater
Suppl
ptional
pansion Tank(* )
Mi ing Valve(*5)
ot ater
Pump(*2)
low Switch(*4)
i tures
ir andler
otes
1. Si e the pump to provide a ma imum of 2 GPM
(7.5 min.) through the s stem at 10 ft ( m) of
head plus piping losses.
d ust the flow using a globe valve and verif the
flow rate with the maintenance monitors.
2. Pump Control Signal is the preferred method
to control the recirculation pump.
or pumps larger than 85 a rela connection
must be used. f the Pump Control Signal is not
used an uastat ma be used to control the
pump.
.
Use an uastat if the water heater is not controlling
the pump.
Set the uastat to 10 (5 C) below the set
output temperature.
4. orit recommends the use of an solation it
with the installation.
These kits include an integrated shut-off and service
valve with unions and a pressure relief valve.
otes
1. orit recommends the use of an solation it with
the installation.
These kits include an integrated shut-off and service
valve with unions and a pressure relief valve.
2. Si e the pump to provide
a ma imum of GPM
(11. min.) with a head pressure e ual to the loss
through the water heater and ir andler.
. Check valve re uired if it is not included with the pump.
4. Set the flow switch to deactivate the ir andler when
the domestic hot water flow reaches GPM (11. min.).
d ust as necessar to prevent c cling.
5. f the s stem re uires water for space heating at a higher
temperature than for other uses means such as a
mi ing valve shall be provided to temper the water for
the other uses to help prevent scalding.
7. The water heater cannot be used for space heating
applications onl .
8. nl P T water ma be plumbed through
the water heater.
. pansion tank re uired if a backflow preventer is installed.
Use one well uastat
(Model 00 or 00 C)
uastat iring
RT
Tankless Gas
ater eater
RT
Tankless Gas
ater eater
11. Plumbing Applications

20
Do not connect electrical o er to the unit until all electrical irin has een com leted.
Consult a qualified electrician
for the electrical or .
12. Electrical Wiring
his a liance must e electricall rounded in accordance ith local codes or in the a sence of local
codes ith the ational lectrical Code S 0. n Canada the latest CS C22.1 lectrical Code.
Caution: a el all ires rior to disconnection hen servicin controls. Wirin errors can cause
im ro er and dan erous o eration.
Verif ro er o eration after servicin .
ield irin to e erformed at time of a liance installation.
he electrical su l re uired the ater heater is
120V C at 60 H .
he o er consum tion ma e u to 2 6W or hi her if
usin o tional accessories.
Use an a ro riate circuit.
Do not disconnect the o er su l hen not in use. When
the o er is off the free e revention in the ater heater
ill not activate resultin in ossi le free in dama e.
Do not let the o er cord contact
the as i in .
ie the redundant o er cord
outside the ater heater. uttin the
redundant len th of cord inside the
ater heater ma cause electrical
interference and fault
o eration.
Disconnect o er
lectrical Shoc Ha ard
Do not turn power on until electrical wiring is finished. Disconnect power before servicing.
Failure to do so may result in death or serious injury from electrical shock.
WARNING
lectrostatic dischar e can affect electronic com onents. a e recautions to revent electrostatic
dischar es from ersonnel or hand tools durin the ater heater installation and servicin to
rotect roduct s electronic control.
CAUTION
Ground
o revent electrical shoc rovide a round ith resistance less than 100 . n electrician should
do this or .
Do not connect the round to the cit ater or as i in . Do not tie the round to a tele hone line.
Breaker Installation
ount a device hich shuts off the electrical ath automaticall (lea a e rea er) hen electrical
lea a e is detected.