Noritz NRC98-DV User manual

SBA8833
Rev. 07/11
Models : NRC98-DV
NRC98-OD
NRC83-DV
NRC83-OD
TANKLESS GAS WATER HEATER
Owner’s Guide
NORITZ America Corporation
- 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
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.
When applicable, installation must conform with the Manufactured Home
Construction and Safety Standard, Title 24 CFR, Part 3280 or the Canadian
Standard CAN/CSA-Z240 MH Mobile Homes, Series M86.
Noritz America reserves the right to discontinue, or change at any time, the
designs and/or specifications of its products without notice.
FOR USE IN RESIDENTIAL OR MANUFACTURED HOME APPLICATIONS.
Low NOx
Approved by
SCAQMD
CERTIFIED
R
*SBA8833*

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 (52°C) 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)
WARNING
Be sure
to do.
When a gas leak is noticed:
1. Stop use immediately
2. Close the gas valve
[NRC98-DV, NRC83-DV]
3. 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 wa-
ter temperature to a higher setting.
Prohibited
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.
(Continued)
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 re-
sult in fire or explosion, and personal injury
or death
Prohibited
[NRC98-DV, NRC83-DV]
Do not use the water
heater if the intake/
exhaust pipe is
displaced, has holes, is
clogged or is corroded.
After the water heater has been out of
use for a long time make sure that you
fill the condensate trap with water.
This is to prevent dangerous exhaust
gases from entering the building.
Failure to fill the condensate trap could
result in severe personal injury or death.
(Refer to page 20 for further instructions.)
Be sure
to do.
Prohibited
[NRC98-OD, NRC83-OD]
Do Not Install Indoors.
This will cause carbon
monoxide poisoning and
a potential fire hazard. Indoor

4
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.
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 separate area that is
supplied with fresh air from outdoors.
Prohibited
Be sure the gas/power
supplied matches the
gas on the rating plate.
Ex. For Natural Gas (NRC98-DV)
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)
Prohibited
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
Prohibited
Do not place or use a spray can near
the water heater or the exhaust vent
terminal.
Do not use hair spray or spray
detergent in the vicinity of the
heater.
Prohibited
Prohibited
[NRC98-DV, NRC83-DV]
Do not place outdoors
Rain may enter the unit
or the burner fire may be
blown by the wind, caus-
ing malfunction or fire as a
result.
Prohibited
Outdoor
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 combustibles such as
laundry, newspapers, oils etc. near the
heater or the exhaust vent terminal.
Prohibited
Do not use combustible chemicals
such as oil, gasoline, benzene etc.
in the near the heater or the exhaust
vent terminal.
Prohibited
Carbon Monoxide Poisoning Hazard.
Do not install this water heater in a
recreation vehicle or on a boat.
Prohibited
WARNING
Left side:
Min. 2" (50mm)
Right side:
Min. 2" (50mm)
Front:
Sug. 24" (600mm)*
Sug.3" (75mm)
from vent pipe*
Upper:
Min. 12" (300mm)
Exhaust vent
terminal
Exhaust vent
terminal
Unit
[NRC98-DV, NRC83-DV]
Left side:
Min. 6" (150mm) Right side:
Min. 6" (150mm)
Upper:
Min. 36" (900mm)
[NRC98-OD, NRC83-OD]
Unit
Front:
Sug. 24" (600mm)*

5
(Continued)
Do not allow small children to play
unsupervised in the bathroom.
Do not allow small children to bath unsupervised.
Do not touch the power
cord with wet hands.
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.
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
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
and exhaust vent 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.
To prevent burns or scalding, turn off the
power button and wait until the equipment
cools before performing maintenance.
The gas conversion kit shall be installed by a
qualified service agency in accordance with
the manufacturer’s instructions and all
applicable codes and requirements of the
authority having jurisdiction. The
information in the instructions must be
followed to minimize the risk of fire or
explosion or to prevent property damage,
personal injury, or death. The qualified
service agency is responsible for the proper
installation of this kit. The installation is not
proper and complete until the operation of
the converted appliance is checked as
specified in the manufacturer’s instructions
supplied with the kit.
Do not use condensate, discharged
from the drain pipe, for drinking or
for consumption by animals.
Prohibited
[NRC98-DV, NRC83-DV] [NRC98-OD, NRC83-OD]

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.
This unit is only approved for installation
up to 4500 ft. (1350m) above sea level.
For installations at higher elevations, contact Noritz
America for Instructions.
Check ignition during use and extinction
after use.
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. 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.
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 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.
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.

7
Important Safety Information....................................................................... 2
Contents......................................................................................................... 7
Overview of Condensing Tankless Gas Water Heater .............................. 8
General Parts
Main Unit.................................................................................................... 9
Remote Controller.................................................................................... 10
Initial Operation............................................................................................ 11
How to Use
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................................................................................... 21
Troubleshooting........................................................................................... 23
Follow-up Service ........................................................................................ 28
Specifications............................................................................................... 30
Contents

8
Cold water Cold water Gas Gas Hot water Hot water
Condensate
Combustion gas
About
400˚F (200˚C)
Exhaust Exhaust
About
120˚F (49˚C)
Conventional
type
Condensing
Tankless Gas
Water Heater
Water is heated
using the exhaust
gas which is about
400˚F (200˚C)
.
Primary heat exchanger
Primary heat exchanger
Secondary heat exchanger
condensate trap
Combustion gas
About
400˚F (200˚C)
About
400˚F (200˚C)
The condensing tankless gas water
heater discharges condensate.
When heat from the exhaust gas is collected within
the secondary heat exchanger, condensation occurs
from moisture in the exhaust gas and the resulting
water is discharged from the drain pipe (approx.
2 gallons/hour (7.5 liters/hour) maximum). It is not a
water leak. Do not plug or block the drain line as it
must always be allowed to freely flow.
Note : The condensate discharged is acidic with a pH
level of approximately 2-3.
A condensate neutralizer may be required by
local code prior to disposal.
Drain pipe
(Installation example)
Overview of Condensing Tankless Gas Water Heater
This water heater is a high efficiency, fully condensing appliance. Unlike a traditional tankless water
heater, a condensing type captures heat from the exhaust gas and uses it to preheat the incoming
cold water as it passes through the secondary heat exchanger as illustrated below.
The condensing tankless gas
water heater tends to show
white steam.
After the exhaust gas passes through the
secondary heat exchanger, it becomes low in
temperature and moisture rich which tends to
produce steam at the vent discharge terminal.
This is a normal occurrence.
Condensate
comes out from
here.
During combustion, white
steam may often be seen.
This is normal.

9
[NRC98-DV, NRC83-DV]
Indoor Wall Mounted, Power Vent/Sealed Model
* The above illustration shows an example of installation.
The exact installation configuration may be slightly different.
Main Unit
Front Cover
Water Supply Valve
Water Drain Valve
(with Water Filter)
(Inside Water Inlet)
(p.22)
Pressure Relief Valve
General Parts -1
Intake Pipe
Flue Collar
Gas Supply Valve
Drain Pipe
Discharges the
condensate.
[NRC98-OD, NRC83-OD]
Outdoor Wall Mounted, Power Vented Model
Exhaust Vent

10
Remote Controller (RC-7651M)
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)
What is actually displayed depends on how the water heater is set.
A number will flash if
a failure occurs.
(p.26 - 27)
Priority Indicator
Burner On Indicator
When burning, the
indicator is lit.
( p.13 and 15)
Note: As shipped from the factory, the remote controller is set to display in °F and gallons.
To adjust the display to °C and liters, refer to the Installation Manual.
General Parts -2

11
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
Do not touch with wet hands.
(Ex. NRC98-DV)

12
Remote controller Display
Press the Power
On/Off Button.
How to Use
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 (52°C) 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 / 55°C (131°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
(52°C) 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 / 50°C (122°F)
or less.
* Consult local codes for minimum operating temperatures.
100 105 110 115 120 125 130 135 140
Shower, hot water supply, etc.
Washing
dishes, etc.
High temperature
The maximum output temperature can be
set using the remote controller. ( p.17)
(°C (°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 40°C (104°F)
Shower, hot water supply, etc.
Washing
dishes, etc.
High
temperature
37 38 39 40 41 42 43 44 45 46 47 48 50 55 60
(99) (100) (102) (104) (106) (108) (109) (111) (113) (115) (117) (118) (122) (131) (140)
The maximum output temperature
can be set using the remote
controller. ( p.17)
When using °F mode:
When using °C mode:
( )

14
How to Use
Flow Meter Alarm
3
2,3
1
2
Set temperature.
Press the Power
On/Off Button
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
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.
On Check the indicator lights.
Water temperature
Previous set temperature (example:40°C)
When the display setting is in Celsius.
When the display
setting is in Fahrenheit.
( )

15
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.
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 gallon (40 - 240L) (In 5 gallon (20L)
intervals), 70 gallon (260L), 80 gallon (300L),
90 gallon (340L), 100 gallon (380L) , 990 gallon.
Note: The alarm will not sound if it is
set for 990 gallon.
Note: The alarm will not sound
if it is set for 990 gallon.
On
Flow meter setting will be flashing
(ex. 45 gallon)
Off
The alarm will sound when
the set level has been
reached. Stop the water.
* The level can only be adjusted
while the indicator is flashing.
* After ten seconds, the remote
will again display the temperature.
On
Flow meter setting will be flashing (ex. 180L)
Off
* Initial factory setting: 110°F or 40°C (104°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.
(°C (°F) : )
Warmer HotWarm
37 38 39 40 41 42 43 44 45 46 47 48
(99) (100) (102) (104) (106) (108) (109) (111) (113) (115) (117) (118)
100 105 110 115 120
Warmer HotWarm
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 : )

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
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 / 55°C (131°F) or higher will
not emit a sound when muted.

17
How to Use
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
(For Fahrenheit (°F))
100°F, 105°F, 110°F, 115°F, 120°F,
125°F, 130°F, 135°F or 140°F.
(For Celsius (°C))
37°C, 38°C, 39°C, 40°C, 41°C, 42°C,
43°C, 44°C, 45°C, 46°C, 47°C, 48°C,
50°C, 55°C or 60°C.
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.)
Take the measures below for extremely cold temperatures*.
(outside temperature including wind chill factor less than -30°F (-35°C) for NRC98-DV, NRC83-DV
or -4°F (-20°C) for NRC98-OD, NRC83-OD.
* For models NRC98-DV and NRC83-DV, when combustion air is supplied from the indoors,
the air temperature must be greater than -4°F (-20°C) to prevent freezing.
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 gallon (400cc)/minute or about 0.2" (4mm) thick.)
* If there is a mixing valve, set it to the highest level.
* When linking multiple units, discharge water equivalent to
(0.1 gallon (400cc)/minute per unit.)
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.
* 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.
Preventing Damage from Freezing-1
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 (-35°C) for NRC98-DV, NRC83-DV or -4°F (-20°C)
for NRC98-OD, NRC83-OD.
* For models NRC98-DV and NRC83-DV, when combustion air is supplied from the indoors,
the air temperature must be greater than -4°F (-20°C) to prevent freezing.
* 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.
0.2" (4mm)
thick
Hot Water Fixture

19
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
CAUTION
1. Close the gas valve.
2. Turn off ther power button.
3. 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.
Drain water into a bucket to prevent water damage.
Fixture
Do not touch with wet hands.
Drain Plugs
Each drain plug mignt not be visible
if insulation is installed around the
piping.

20
Preventing Damage from Freezing-2
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.11 “Initial operation”, steps 1 through 4.
4. Make sure that the area around the appliance 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 water heater, 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.)
* If water does not appear at the end of the drain line, a qualified service technician must clean the
condensate line.
After the water heater has been out of use for a long time make sure that you fill
the condensate trap with water.
This is to prevent dangerous exhaust gases from entering the building.
Failure to fill the condensate trap could result in severe personal injury or death.
(By performing step 4 as described above, the condensate trap will automatically
fill itself with water.)
Be sure to do.
DANGER