Noritz N-0631S User manual

SAR8583-2
Rev. 03/08
Model N-0631S
N-0631S-OD
N-0531S
N-0531S-OD
TANKLESS GAS WATER HEATER
Owner’s Guide
NORITZ America Corporation
Thank you for purchasing this Noritz Tankless Gas Water Heater.
Before using, please:
Read this manual completely for operation instructions.
Completely fill out the warranty registration card (included separately) and
mail the detachable portion to Noritz America Corporation.
Keep this manual (and the remainder of the warranty registration card) where it
can be found whenever necessary.
Installation must conform with local codes, or in the absence of local codes,
the National Fuel Gas Code, ANSI Z223.1/NFPA 54.
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
CERTIFIED
R
- Do not store or use gasoline or other flammable vapors and liquids in the
vicinity of this or any other appliance.
-WHAT TO DO IF YOU SMELL GAS
•Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in your building.
• Immediately call your gas supplier from a neighbor’s phone. Follow the
gas supplier’s instructions.
•If you cannot reach your gas supplier, call the fire department.
- Installation and service must be performed by a qualified installer, service
agency or the gas supplier.
If the information in this manual is not followed exactly, a fire or explosion
may result causing property damage, personal injury, or death.
WARNING
*SAR8583 T*

2
Prohibited Don’t
touch.
Don’t
disassemble
the equipment.
Don’t touch
with a wet
hand.
No flame.
High
Temperature.
To prevent damage to property and injury to the user, the icons shown below will be used to warn of
varying levels of danger.
Every indication is critical to the safe operation of the water heater and must be understood and observed.
Potential dangers from accidents during installation and use are divided into the following four
categories. Closely observe these warnings; they are critical to your safety.
Other icons
DANGER
WARNING
CAUTION
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.
CAUTION used without the safety alert symbol indicates a potentially
hazardous situation which, if not avoided, may result in property damage.
CAUTION
Be sure
to do. Ground.
Electric
Shock.
DANGER
Icons warning of risk level
Important Safety Information-1
This is the safety alert symbol. It is used to alert you to potential personal injury hazards.
Obey all safety messages that follow this symbol to avoid possible injury or death.
Vapors from flammable liquids will explode and catch fire causing death or severe burns.
Do not use or store flammable products such as gasoline, solvents or
adhesives in the same room or area near the water heater.
Prohibited
Keep flammable products:
1. Far away from the water
heater.
2. In approved containers.
3. Tightly closed.
4. Out of children’s reach.
Vapors:
1. Cannot be seen.
2. Vapors are heavier than air.
3. Go a long way on the floor.
4. Can be carried from other rooms
to the main burner by air currents.
Hot Water Heater temperatures over 125 °F can cause severe burns instantly or
death from scalding.
Children, disabled and elderly are at the highest risk of being scalded.
Feel water temperature before bathing or showering.
Temperature limiting valves are available, ask professional person.
Prohibited
(Continued)

3
No flame.
(Continued)
[N-0631S, N-0531S]
Do not use the water heater if
the exhaust pipe is displaced,
has holes, is
clogged or
is corroded.
Prohibited
WARNING
Be sure
to do.
When a gas leak is noticed:
1. Stop use immediately
2. Close the gas valve
3. [When installing indoors]
Open windows and doors
If you detect abnormal combustion
or abnormal odors, or during an
earthquake, tornado or fire:
1. Turn off the hot water supply
2. Turn off the power to the water
heater
3. Turn off gas and water supply valve.
4. Call the nearest Noritz agent
Be sure
to do.
Do not allow anyone to change the water temperature while hot water is being used .
To prevent scalding, do not change the water temperature to a higher setting.
Prohibited
Check the temperature
of the running hot water
before entering the
shower.
Check the temperature
before stepping into
the bath tub.
High
Temperature.
Explosion Hazard ;
If the temperature and pressure relief
valve is dripping or leaking, have a
qualified service technician replace it.
Do not plug or remove the valve.
Failure to follow these instructions can result
in fire or explosion, and personal injury or
death
Prohibited
(Continued)
Prohibited
[N-0631S-OD, N-0531S-OD]
Do Not Install Indoors.
This will cause carbon
monoxide poisoning and
a potential fire hazard.
Indoor
A. This water heater does not have a
pilot. It is equipped with an
ignition device that automatically
lights the burner. Do not try to
light the burner by hand.
B.
BEFORE OPERATING smell all
around the water heater area for
evidence of leaking gas. Be sure to
smell next to the floor because
some gas is heavier than air and will
settle on the floor.
WHAT TO DO IF YOU SMELL GAS.
• Do not try to light any appliance.
• Do not touch any electrical
switch; do not use any phone in
your building.
•
Immediately call your gas supplier
from a neighbor’s phone. Follow
the gas supplier’s instructions.
• If you cannot reach your gas
supplier, call the fire department.
C. Use only your hand to turn the gas
valve knob. Never use tools. If the
knob will not turn by hand, don’t
try to repair it. Call a qualified
service technician. Force or
attempted repair may result in a
fire or explosion.
D. Do not use this water heater if any
part has been under water.
lmmediately call a qualified
service technician to inspect the
water heater and to replace any
damaged parts.

4
Important Safety Information-2
(Continued)
If this unit will be installed in a beauty
salon or other location where hair
spray or aerosols will be used, locate
the unit in a seperate area that is
supplied with fresh air from outdoors.
air supply
vent
[When installing indoors (N-0631S, N-0531S)]
Check the air supply
vent for dust or
obstructions.
Be sure
to do.
Prohibited
Be sure the gas/power
supplied matches the
gas on the rating plate.
Ex. For Natural Gas N-0631S
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
Be sure
to do.
Be sure
to do.
(Continued)
Leave the proper clearance between
the water heater and nearby objects
(trees, timber, boxes with flammable
materials etc.).
Be sure
to do.
*Indicates suggested clearances for maintenance.
Do not place the exhaust vent terminal
in an indoor environment by means of
adding walls and ceiling (Do not en-
close using corrugated sheets, etc.)
Carbon monoxide poisoning or fire may
occur as a result.
Exhaust
vent terminal
Outdoor
Unit
Prohibited
Do not place combustibles such as
laundry, newspapers, oils etc. near the
heater or the exhaust vent terminal.
Exhaust vent terminal
(indoor installation)
Prohibited
Carbon Monoxide Poisoning Hazard. Do
not install this water heater in a mobile
home, recreation vehicle or on a boat.
Prohibited
Do not use combustible chemicals
such as oil, gasoline, benzene etc.
in the near the heater or the exhaust
vent terminal.
Do not store or use gasoline or
other flammable vapors and liquids
in the vicinity of this or any other
appliance.
Prohibited
Prohibited
Do not place or use a spray can
near the heater or the exhaust vent
terminal.
Prohibited
Left side:
Min. 6" Right side:
Min. 6"
Front:
Sug. 24"
Upper: Min. 36"
[When installing indoors (N-0631S, N-0531S)]
[When installing outdoors]
Unit
180,000
148,000
2.4
2.25" 2.25"
2.4
173,600
142,000
180,000 BTU
180,000 BTU
25,000 BTU
25,000 BTU
177
177
4.0"
4.0"
0.55"
0.55"
2.25"
2.25"
10.5"
10.5"
670
670
2004
15 150
N-0631S
N-0631S
Left side: Min. 2" Right side:
Min. 2"
Upper:
Min. 12"
Front: Sug. 24"*
Sug. 3" from
vent pipe

5
CAUTION
Be sure to electrically ground the
unit.
Keep power cord free of dust.
Ground.
Be sure
to do.
Do not use the water heater for
other than hot water supply, shower
and bath.
Prohibited
(Continued)
Prohibited
Do not cover the water heater and
the exhaust vent terminal, store
trash or debris near it, or in any way
block the flow of fresh air to the unit.
Do not turn off the water heater
while someone is bathing.
Prohibited
Do not use a broken or modified
power cord. Do not bind, bend or
stretch power cords.
Do not scratch, modify, or subject
them to impact or force.
Do not touch the exhaust vent (pipe,
terminal) during or immediately after
operation of the water heater.
Do not install in locations where
excessive dust or debris will be
in the air.
Prohibited Don’t
touch.
Prohibited
Be sure
to do.
Do not allow small children to play
unsupervised in the bathroom.
Do not allow small children to
bathe unsupervised.
Do not use hair spray or spray
detergent in the vicinity of the
heater.
Do not touch the power
cord with wet hands.
Prohibited
Electric
Shock.
Don’t touch
with a wet
hand.
Prohibited
Contact Noritz before using with
a solar pre-heater.
Contact a qualified service
technician for any necessary
repairs, service or maintenance.
Consult the nearest Noritz agent if
the water heater location needs to
be changed.
Don’t
disassemble
the equipment.
Be sure
to do.
Be sure
to do.
California Proposition 65 lists chemical
substances known to the state to cause
cancer, birth defects, death, serious illness
or other reproductive harm. This product
may contain such substances, be their
origin from fuel combustion (gas, oil) or
components of the product itself.
To prevent burns or scalding, turn
off the power button or power supply
and wait until the equipment cools
before performing maintenance.

6
Important Safety Information-3
CAUTION
Do not drink water that has been inside the
unit for an extended period of time. Do not
drink the first use of hot water from the
unit in the morning.
Clean the filter on the water inlet as
frequently as required by the quality of
your local water.
Keep the area around the unit clean.
If boxes, weeds, cobwebs, cockroaches etc. are in
the vicinity of the unit, damage or fire can result.
Do not install the equipment where the
exhaust will blow on walls or windows.
Problems resulting from scale formation
are not covered by the warranty.
Preventing damage from freezing ( p.18)
Damage can occur from frozen water within the
device and pipes even in warm environments.
Be sure to read below for appropriate measures.
Repairs for damage caused by freezing are not
covered by the warranty.
This unit is only approved for installation
up to 4500 ft. above sea level.
For installations at higher elevations, contact Noritz
America for Instructions.
Check ignition during use and extinction
after use.
Do not run water through the unit when
unit is not on.
When discharging hot water, make sure the unit is ON.
If water is run through the unit with the unit
OFF, water may condense inside the unit and cause
incomplete combustion or damage to the internal
electrical components.
For single-handle fixtures or valves, discharge
water setting the handle completely
to the water side.
Take necessary measures to prevent
freezing of water and leakage of gas when
leaving the unit unused for long periods of
time. ( p.19)
Do not use parts other than those specified
for this equipment.
If it is snowing, check the air inlet, exhaust
gas vent and exhaust vent terminal for
blockage.
Do not disassemble the remote controller.
Do not use benzene, oil or fat detergents
to clean the remote controller.
This may cause deformation.
Do not get the remote controller wet.
Although it is water resistant, too much water can
cause damage.
Do not splash water on the remote
controller. Do not expose the remote
controller to steam.
Do not locate the remote controller near stoves or
ovens, this may cause damage or failure.
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.

7
Important Safety Information....................................................................... 2
Contents ........................................................................................................ 7
General Parts
Main Unit.................................................................................................... 8
Remote Controller .................................................................................... 9
Initial Operation ........................................................................................... 10
How to Use (Not using the remote controller)
Setting and Using the Water Heater........................................................ 11
How to Use (Using the remote controller)
Setting and Using the Water Heater........................................................ 12
Flow Meter Alarm ...................................................................................... 14
Muting the Remote Controller ................................................................. 16
Adjusting the Maximum Output Temperature........................................ 17
Preventing Damage from Freezing ............................................................ 18
Regular Maintenance................................................................................... 20
Troubleshooting .......................................................................................... 22
Follow-up Service ........................................................................................ 26
Specifications .............................................................................................. 27
Contents

8
N-0631S, N-0531S
Indoor/Outdoor Wall Mounted, Power Vented Model
* The above illustration shows an example of installation.
The exact installation configuration may be slightly different.
Main Unit
Flue Collar
Front Cover
Air Inlet
Water Supply Valve
Gas Supply Valve
Water Drain Valve (with Water Filter)
(Inside Water Inlet) (p.21)
Pressure Relief Valve
General Parts
N-0631S-OD, N-0531S-OD
Outdoor Wall Mounted, Power Vented Model
Exhaust Vent
Front Cover
Air Inlet
Water Supply Valve
Gas Supply Valve
Water Drain Valve (with Water Filter)
(Inside Water Inlet) (p.21)
Pressure Relief Valve
(Ex. N-0631S)
(Ex. N-0631S-OD)

9
Remote Controller (RC-7649M) <Optional>
For setting the hot
water temperature,
the flow meter alarm,
and other settings.
Power On/Off Button
For turning the
heater on and off.
Flow Meter Alarm Set Button
For setting the flow
meter alarm.
(p.14 - 15)
Setting Buttons
* Before use, remove the protective sheet from the remote controller surface.
Temperature Setting
(Ex.: 110°F)
Flow Meter Setting
The display will flash
after hitting the flow
meter alarm set button.
(p.15)
Error Code
When this indicator is lit,
the hot water temperature
can be set. ( p.12)
The illustration below shows the remote controller display. What is actually displayed
depends on how the water heater is set.
A number will flash if
a failure occurs.
(p.25)
Priority Indicator
Burner On Indicator
When burning, the
indicator is lit.
( p.13 and 15)

10
(Ex. N-0631S)
Initial Operation
Before the first use of your water heater, make the following preparations.
Follow steps 1 through 4.
1Open the water supply valve.
Open a hot water fixture to confirm that
water is available, and then close the
fixture again.
3Open the gas supply valve.
Hot water fixture
2
Turn on the power.
CLOSED
4
OPEN

11
3
Mix for desired temperature.
The factory temperature setting is 120°F (fixed). Mix with cold water with a mixing valve
or at the fixture for desired temperature.
To prevent scalding.
1Check that electrical power is connected.
2
4
How to Use (Not using the remote controller)
Setting and Using the Water Heater
If you want to the temperature to be changed to 130°F or 140°F, contact the installer or Noritz.
Turn on hot water.
Turn off the hot water.
DANGER
High Temperature
The electrical power does not need to
be disconnected between uses.
Hot water
Water
Hot Water Heater temperatures over 125°F can cause
severe burns instantly or death from scalding.
•Children, disabled and elderly are at the highest risk of being scalded.
Feel water temperature before bathing or showering.
Temperature limiting valves are available, ask professional person.

12
Remote Controller Display
Press the Power
On/Off Button.
How to Use (Using the remote controller)
Setting and Using the Water Heater
Previous set
temperature
(Ex.: 110°F)
The temperature will be
displayed on the remote
control thermostat.
1
2(Starting with the Power Off)
On
On
High Temperature
To prevent scalding:
Flashes for 10 sec
1
DANGER
Hot Water Heater temperatures over 125°F can cause
severe burns instantly or death from scalding.
•Children, disabled and elderly are at the highest risk of being scalded.
Feel water temperature before bathing or showering.
Temperature limiting valves are available, ask professional person.
• When setting the unit to 125°F or higher, the temperature
display will flash for 10 seconds and emit a tone as a high
temperature warning.
•Take caution when using the unit again after setting to 125°F
or higher. Always check the set temperature before use.
• Do not allow anyone to change the water temperature while
hot water is running.

13
4
3Turn on hot
water.
2
Set temperature.
Turn off the hot
water.
(
Always check the
)
temperature setting
before use.
Hot
Cold
Check the indicator lights.
Water temperature
On Off
(°F: )
The temperature settings below are examples. The temperature setting
necessary depends on the usage, the length of piping and the time of year.
*Initial factory setting is 110°F
If fixtures incorporate mixing valves,
set the temperature higher than usual.
* For most residential applications, the recommended setting temperature is 120°F or less.
For applications that occasionally require a higher temperature setting, locate the remote controller
in a convenient location.
* Consult local codes for minimum operating temperatures.
Shower, hot water supply,
etc.
Washing
dishes, etc.
High temperature
Contact the installer or Noritz
America when setting the
maximum output temperature
in this range.
The maximum output tempera-
ture can be set using the re-
mote controller. ( p.17)
100 105 110 115 120 125 130 135 140 145 150 160

14
How to Use (Using the remote controller)
Flow Meter Alarm
3
2,3
1
2
Set temperature.
Press the Power
On/Off Button
1. Plug the bath drain.
Preparation
(Starting with the power off)
(
Always check
)
temperature setting
before use.
Hot
Cold
On
The temperature will be displayed
on the remote control thermostat.
Previous set temperature
(example:110°F)
On Check the indicator lights.
Water temperature
1

15
100 105 110 115 120
An alarm will sound for ten
seconds when the flow
reaches the set level.
The water will continue to run unless it is
manually turned off. * Initial factory setting: 110°F
Water Temperature
The temperatures settings below are only examples. The
temperature setting necessary will depend on the usage,
the length of piping and the time of year.
(°F: )
Warmer HotWarm
5Turn off the hot
water when the
alarm sounds.
4Turn on hot
water.
3Adjust flow meter
alarm setting.
To set the flow meter alarm:
Press the flow meter alarm set button
(the setting will flash on the display)
and adjust with the setting buttons.
Increase
Decrease
Choose the flow meter alarm setting
from the following options: 10 - 60
(In 5 gallon intervals), 70 - 100 (In
10 gallon intervals), or 990 gallons.
Note:
The alarm will not sound if
it is set for 990 gal.
Note:
The alarm will not
sound if it is set for
990 gal.
On
Flow meter setting will be flashing
(ex. 45 gal.)
*The level can only be adjusted
while the indicator is flashing.
* After ten seconds, the remote
will again display the temperature.
Off
If the flow meter alarm is being used to indicate when a tub is full:
•If any hot water is being used besides what is going into the tub, the alarm will sound before
the tub is full.
•If there was water in the tub before the fill began, or if the water is not shut off manually when
the alarm sounds, the tub may overflow.
•If there was water in the tub before the fill began, the temperature in the tub after it is full may
be different from the temperature setting.
The alarm will sound when
the set level has been
reached. Stop the water.

16
The remote controller will emit a sound
when any button is pushed. This sound
can be muted if it is desired.
1
How to Use (Using the remote controller)
Muting the Remote Controller
* Initial factory setting is with sound
Sound
Muted
No sound
after 5 sec.
1Hold the Power On/Off
Button for five seconds.
Tone sounds
after 5 sec.
• The flow meter alarm cannot be muted.
• The high temperature warning tone when setting the unit to 125°F or higher will not emit a sound
when muted.

17
How to Use (Using the remote controller)
Adjusting the Maximum Output Temperature
2
3
1
3
Change the
temperature using
the setting buttons.
Press and hold the flow
meter alarm set button until
a sound is heard (2 sec.).
Up
Down
The upper limit of the hot-water
supply temperature can be
changed to 100°F, 105°F,
110°F, 115°F, 120°F, 125°F,
130°F, 135°F or 140°F.
2
Turn off the
power.
Off
1
Set the Power button to ON when continuing to use
the unit as is. Otherwise, let the unit sit for 30 sec.
4
Tone sounds
after 2 sec.

18
*Damage can occur from frozen water within the device and pipes even in warm environments.
Be sure to read below for appropriate measures.
*Repairs for damage caused by freezing are not covered by the warranty.
Freezing cannot be prevented when the power plug is unplugged. Do not remove the power
plug from the wall outlet.
(Freezing will be prevented regardless of whether the operation switch is ON or OFF.)
* Remember to set mixing valves and fixtures to their original levels before using the unit again
to prevent scalding.
* If there is still a risk that the unit will freeze, drain the unit as shown on the next page.
0.2" thick
Hot Water Fixture
Preventing Damage from Freezing
Freezing is prevented within the device automatically by the freeze-prevention heater
If water will not flow because it is frozen
1. Close the gas and water valves.
2. Turn off the power button.
3. Open the water supply valve from time to time to check whether water is running.
4. When the water is flowing again, check for water leaks from the equipment and piping
before using.
If the heater or the piping is frozen, do not use the heater or it may get damaged.
CAUTION
* In normal operation, freezing is prevented within the device automatically unless the outside
temperature without wind is below -30°F (indoor installation) or -4°F (outdoor installation).
* The freeze prevention heaters will not prevent the plumbing external to the unit from freezing.
Protect this plumbing with insulation, heat tape or electric heaters, solenoids, or pipe covers.
If there remains a freezing risk, contact the nearest Noritz agent.
Take the measures below for extremely cold temperatures*. <Only using the remote controller>
(outside temperature including wind chill factor less than -30°F (indoor installation) or
-4°F (outdoor installation)).
This method can protect not only the heater, but also the water supply,
water piping and mixing valves.
1. Turn off the power.
2. Close the gas supply valve.
3. Open a hot water fixture, and keep a small stream of hot water running.
(0.1 gal/minute or about 0.2" thick.)
* If there is a mixing valve, set it to the highest level.
4. The flow may become unstable from time to time. Check the flow 30
minutes later.
* In general, it is not advisable to run water through the unit when
it is OFF ( p. 6), but in this case freeze prevention is more important.

19
1. Close the gas valve.
2. <Not using the remote controller>
Fully open one of the hot water fixtures.
<Using the remote controller>
Turn off ther power button.
3. <Not using the remote controller>
Turn off the power supply after 20 seconds or more pass from operation of 2.
<Using the remote controller>
Turn off the power supply.
4. Close the water supply valve.
5. Fully open all hot water fixtures.
6. Turn the drain plug to the left to open, and then remove.
7. Check that the water is completely drained, close all the
drain plugs and the hot water fixtures after 10 minutes
or more pass from operation of 6.
If the water heater will not be used for a long period of time,
Drain the water.
Drain the water as follows:
To avoid burns, wait until the equipment cools down before draining the water.
The appliance will remain hot after it is turned off.
High Temperature
Drain water into a bucket to prevent water damage.
Do not touch with wet hands.
Fixture
Fixture
Turning the Unit Back On
1. Check that all drain plugs are inserted.
2. Check that all hot water fixtures are closed.
3. Follow the procedure on p.10 “Initial operation”, steps 1 through 4.
CAUTION
Do not touch with wet hands.
Drain Plugs
Each drain plug mignt not be visible
if insulation is installed around the
piping.

20
(Ex. N-0631S)
Periodic Maintenance
Wipe the outside surface with a wet cloth, then dry the surface. Use a neutral detergent to
clean any stains.
•Do not use benzene, oil or fatty detergents to clean the remote controller;
deformation may occur.
•The remote controller is water resistant but not water proof. Keep it as dry as possible.
Regular Maintenance
Periodic Inspection
Check
For laundry, newspaper, timber,
oil, spray cans and other
combustible materials.
Equipment
Remote Controller
Wipe the surface with a wet cloth.
For abnormal sounds
during operation.
For abnormalities in
external appearance,
discoloration or flaws.
For water leaks from the
equipment and piping.
For dust or debris in
the air inlet.
For dust and soot in
the exhaust vent or
exhaust vent terminal.
For proper operation of
pressure relief valve.
Check
Check
Check
Check
Check
Check
CAUTION
To prevent burns or scalding, turn off the power button or power supply and
wait until the equipment cools before performing maintenance.
Be sure to do.