Navien NPE-24AWE Guide

ƔThese appliances are for use with natural gas or LPG.
(An LPG conversion kit is included with the water
heater.)
ƔType: B23-B33-B53-C13-C33-C43-C53-C63-C83
Keep this manual near this water heater for future reference
whenever maintenance or service is required.
Model
NPE-24AWE
NPE-24SWE
NPE-32AWE
NPE-32SWE
User’s
Information
Manual
WARNING
If the information in these instructions is not followed exactly, a fire or explosion may
result, causing property damage or personal injury.
– Do not store or use petrol or other flammable vapours and liquids in the vicinity of this or
any other appliance.
– WHAT TO DO IF YOU SMELL GAS
ƔDo not try to light any appliances.
ƔDo not touch any electrical switch; do not use any phone in your building.
ƔImmediately call the National Gas Emergency Helpline on (Freephone) 0800 111999 or your gas
supplier from a neighbour’s phone. Follow the instructions received.
– Installation and service must be performed by a Gas Safe registered installer, service
agency or the gas supplier.
Condensing Water Heater

2 Contents
Contents
1. Safety Information 3
2. About the Water Heater 8
2.1 Description of the Water Heater 8
2.2 Parts of the Water Heater 8
2.3 The Front Panel 9
3. Operating the Water Heater 10
3.1 Turning the Water Heater On or Off 10
3.2 Adjusting the Water Temperature 10
3.3 Viewing Basic Information 11
3.4 Resetting the Water Heater 11
4. Troubleshooting 12
4.1 Solving Basic Problems 12
4.2 Understanding Error Codes 13

Safety Information 3
WARNING
If you do not follow these instructions
exactly, a fire or explosion may result
causing property damage or personal
injury.
A. This appliance does not have a pilot.
It is equipped with an ignition device
which automatically lights the burner.
Do not try to light the burner by hand.
B. BEFORE OPERATING smell all around
the appliance area for gas. Be sure to
smell next to the floor because some
gases are heavier than air and will
settle on the floor.
WHAT TO DO IF YOU SMELL GAS
ƔDo not try to light any appliances.
ƔDo not touch any electric switch; do
not use any phone in your building.
ƔImmediately call the National Gas
Emergency Helpline on (Freephone)
0800 111999 or your gas supplier
from a neighbour’s phone. Follow
the instructions received.
C. Do not use this appliance if any part
has been under water. Immediately
call a qualified service technician to
inspect the appliance and to replace
any part of the control system and
any gas control which has been under
water.
The following safety symbols are used in this manual. Read and
follow all safety instructions in this manual precisely to avoid
unsafe operating conditions, fire, explosion, property damage or
personal injury. Keep this manual for future reference.
DANGER
Indicates an imminently hazardous
situation which, if not avoided, could
result in severe injury or death.
WARNING
Indicates a potential hazardous situation
which, if not avoided, may result in injury
or death.
CAUTION
Indicates a potentially hazardous
situation that, if not avoided, could result
in property damage.
1. Safety Information

4 Safety Information
DANGER
HOT
BURN
To prevent burns:
ƔUse the lowest operating temperature
setting necessary to provide
comfortably-hot water.
ƔIf your household has children or
elderly or disabled residents, consider
using a lower temperature setting.
ƔRead all the instructions in this
manual carefully before changing the
temperature setting.
ƔFeel the water before using it on
children, the elderly or the disabled.
ƔIf it is necessary to set the water heater
above 52°C, have a temperature-
limiting valve or mixing valve installed
on the water heater.
WARNING
This appliance can be used by children
aged from 8 years and above and
persons with reduced physical, sensory
or mental capabilities or lack of
experience and knowledge provided
they have been given supervision or
instruction concerning to the use of the
appliance in a safe way and understand
the hazards involved. Children shall not
play with the appliance. Cleaning and
user maintenance shall not be made by
children without supervision.

Safety Information 5
WARNING
ƔShut off the gas supply if the water
heater is damaged.
Have your installer or plumber show
you the location of the gas shut
off valve and demonstrate how to
close the valve. If the water heater is
damaged as a result of overheating,
fire, flood or any other reason, close
the manual shut off valve and do not
operate the water heater again until
it has been inspected by a qualified
technician.
ƔDo not store or use petrol or other
flammable liquids near this water
heater.
Doing so may result in fire or explosion.
ƔDo not place combustibles, such as
newspapers or laundry, near the
water heater or flue system.
Doing so may result in a fire.
ƔDo not place or use hair sprays, spray
paints or any other compressed
gases near the water heater or
flue system, including the flue
termination.
Doing so may result in fire or explosion.
DANGER
This water heater is set to 50°C at the
factory for your safety and comfort.
Increasing the temperature increases
the risk of accidental scalding. Water
temperatures at or above 52°C can cause
instant scalding or severe burns. Before
you decide to change the temperature
setting, read the following charts
carefully.
Water
Temperature
Time in which a young child can suffer a
full thickness (3rd degree) burn*
70°C Less than 1 second
60°C 1 second
55°C 10 second
49°C 10 minutes
37°C very low scald risk
Before setting the temperature at or above
52°C, consider installing a thermostatically-
controlled mixing valve or temperature-
limiting valve. Contact a licensed plumber
or your local plumbing authority for more
information.

6 Safety Information
CAUTION
ƔDo not attempt to repair or replace
any part of the water heater, unless
it is specifically recommended in this
manual.
For all other service, contact an
authorised technician or licensed
professional. Improper adjustments,
alterations, service, or maintenance
may lead to property damage, personal
injury and will void your warranty.
ƔDo not operate the water heater if
you feel something is wrong with it.
Doing so may result in product damage
or personal injury.
ƔDo not allow children to operate or
access the water heater.
Doing so may result in product damage
or personal injury.
ƔDo not attempt to change the water
temperature while the water heater
is being used.
Doing so may result in personal injury.
ƔDo not turn on the water heater
unless the water and gas supplies
are fully opened.
Doing so may damage the water
heater.
ƔDo not turn on the water if the cold
water supply shut-off valve is closed.
Doing so may damage the water
heater.
ƔDo not use this water heater for
anything other than its intended
purpose, as described in this manual.
ƔDo not operate the water heater with
the front cover opened.
Doing so may result in fire or carbon
monoxide (CO) poisoning, which may
result in property damage or personal
injury.
ƔDo not operate this water heater
without proper flue system.
Doing so may result in fire or carbon
monoxide (CO) poisoning, which may
result in property damage or personal
injury. Inspect the flue termination
and air intake supply annually to
ensure proper operation of the water
heater. Turn off and discontinue use
of the water heater if any of the flue
pipes, flue elbows or intake pipes are
damaged in any way, separated at a
joint or show evidence of corrosion,
rusting or melting.
ƔDo not touch the power cord or
internal components of the water
heater with wet hands.
Doing so may result in electric shock.
ƔDo not make any electrical
connections before turning off the
electrical power supply at service
entrance panel.
Doing so may result in severe personal
injury.

Safety Information 7
EC Conformity Declaration
006
3
Navien, hereby declares that the water heater models:
NPE-24AWE, NPE-24SWE, NPE-32AWE, NPE-32SWE
to which this declaration refers, conform to and comply with
the essential requirements of the following applicable European
Standards and Directives.
Gas appliances: Directive 2009/142/EC Standards EN 437 and
EN 26
Water Heater Efficiency: Directive 92/42/EEC
Regulation (EU) No. 814/2013
Regulation (EU) No. 812/2013
Low voltage:
Directive 2006/95/EEC
Electro-magnetic Compatibility: Directive 2004/108/EEC
Noise: Standard EN 15036-1, EN-ISO 3743-1
Navien, manufactures its products using a Quality Assurance
system in compliance with Standard EN-ISO 9001:2000.
ƔDo not remove the front cover unless
the power to the water heater is
turned off or disconnected.
Failure to do so may result in electric
shock.
ƔWhen servicing the controls, label all
wires prior to disconnecting them.
Failure to do so may result in wiring
errors, which can lead to improper or
dangerous operation.
ƔDo not use unapproved replacement
or accessory parts.
Doing so may result in improper or
dangerous operation and will void the
manufacturer’s guarantee.
ƔDo not place anything in or around
the flue terminals, such as a clothes
line, that could obstruct the air flow
in or out of the water heater.
ƔThis water heater has been approved
for use in the UK and Ireland only.
Using the water heater in any other
country will void the manufacturer’s
guarantee.
ƔShould overheating occur or the gas
supply fail to shut off, turn off the
manual gas valve to the appliance.
ƔDo not use this appliance if any part
has been under water.
Immediately call a qualified service
technician to inspect the appliance
and to replace any part of the control
system and any gas control which has
been under water.

8 About the Water Heater
2.2 Parts of the Water Heater
Coaxial
(Intake/Exhaust)
Bottom View
a
b
c
d
e
f
g
h
#Description Remark
a Pump Drain Port “A” model only
bGasInlet
cHot Water Outlet Connection
dRecirculation Inlet “A” model only
e Condensate Water Clean-out
fInlet Water Filter
gColdWater Inlet Connection
h Condensate Drain Connection
2.1 Description of the Water Heater
The NPE-series water heater is availablein four models: NPE-
24AWE, NPE-24SWE, NPE-32AWE, and NPE-32SWE
The main features are as follows:
Potabledomestic hot water, combination spaceheating, and
commercial applications
Maximum temperature: 85°C
Dual stainless steel Heat Exchangers with stainless steel
piping
Built-in pump and 1.5 litre Buer Tank for internal or external
recirculation (“A” model only)
2. About the Water Heater

About the Water Heater 9
a
b
c
d
e
f
g
h
i
j
k
2.3 The Front Panel
The front panel allows you to adjust the water temperature and
view the operating status or error codes. Remove the protective
sheet from the front panel before using it.
a
Error
g
Master Unit
A code will appear on the display Cascade operation
b
Hot Water Recirculation
h
Display
Recirculation Mode
c
Diagnostics button
i
Up button
For installers only Increases the temperature
d
Information button
j
Down button
Shows basic information Decreases the temperature
e
Reset button
k
Power button
Resets the water heater (When an error occurs) Turns the water heater on or off
f
Combusting
When the gas burner is on

10 Operating the Water Heater
The water heater is set to 48.5°C by default. To adjust the water
temperature:
1. Make sure that all hot water faucets are closed, and ensure
that the internal circulator and any external circulating
pumps are off.
Note If a hot water faucet is open, you can adjust
the temperature only from 37°C-43°C.
2. Press the + (Up) or – (Down) buttons until the desired
temperature appears on the display. You can adjust the
temperature while the display is flashing. Once the display
stops flashing, the temperature setting is stored.
Note The water heater will retain your settings
during a power outage.
You can adjust the temperature by the below 5-degree
increments, depending on the temperature range:
Temperature range Adjusting the water
temperature
36°C-50°C (Celsius mode) 0.5°C increments
50°C-60°C (Celsius mode) Press for 2 seconds to adjust in
2°C increments
The water heater will not provide hot water instantly at the hot
water faucet unless a recirculation line has been installed from
the furthest fixture back to the water heater. For “A”models, the
unit must be set to “external recirculation”mode.
3.1 Turning the Water Heater On or Off
To turn the water heater on or off, press the Power button.
When the power is on, the temperature will appear on the front
panel display.
3.2 Adjusting the Water Temperature
WARNING
Before adjusting the water temperature, read“To prevent
burns:”on page 4 carefully. Water above 50°C can cause
instant scalding or severe burns.
3. Operating the Water Heater

Operating the Water Heater 11
3.4 Resetting the Water Heater
If an error message appears, you can try resetting the water
heater to resolve the problem. To reset the water heater, press
the Reset button.
If resetting the water heater does not solve the problem, refer
to the Troubleshooting section of this manual or contacta
Technical AssistanceService.
3.2.1 Using Commercial Mode
Touse water above 60°C (up to 85°C), you can use Commercial
Mode.
Toenter Commercial Mode: Press the up (+)and down (-)
button simultaneouslyfor 10seconds. “HIGH” appears on the
display.
Toexit Commercial Mode: Press the up (+)and down (-)
button simultaneouslyfor 10seconds. “LoW”appears on the
display.
Note To adjust the temperature, press the up (+) button
for 5 seconds to adjust in 5°C increments.
3.3 Viewing Basic Information
To view information about the water heater, press the
Information button.
Press the + or – buttons to switch between the information
types.
Display Description
Flow rate in litres per minute (LPM).
Hot water outlet temperature (OUT).
Cold water inlet temperature (IN).
To exit information mode, press the Reset button.

12 Troubleshooting
If resetting the water heater and attempting the remedies suggested below do not resolve the problem, contact Navien Technical
Assistance Service (TAS) or a Gas Safe Registered Engineer.
Problem Possible Cause(s) What to do
No water comes out when the hot
water tap is opened.
ƔIs the cold water inlet filter clean?
ƔIs an error code displayed on the front
panel?
ƔIs the water heater frozen?
ƔEnsure that the shut–off valves on the hot
and cold pipes are open.
ƔIf an error code is displayed, refer to
“4.2 Understanding Error Codes”on
page 13.
The water from the hot water faucet
is cold or turns cold and stays cold.
ƔIs the cold water inlet filter clean?
ƔIs the hot water faucet open wide enough
draw at least 1.9 litres of water per minute
(LPM) through the water heater?
ƔIs an error code displayed on the front
panel?
ƔIf there is an external recirculation system
installed, is there a check valve on the
recirculation return line?
ƔClean the cold water inlet filter.
ƔOpen the hot water faucet completely.
ƔIf an error code is displayed, refer to
“4.2 Understanding Error Codes”on
page 13.
It takes too long for hot water to
reach the fixtures. Are you using the external recirculation mode?
Have a contractor install a recirculation return
line from the furthest faucet back to the
water heater.
The water is not hot enough. Is the set temperature too low?
ƔCheck the water heater’s temperature
setting. Refer to “3.2 Adjusting the Water
Temperature”on page 10.
ƔCheck for cross plumbing between the
cold and hot water lines.
The water is too hot. Is the set temperature set too high?
Check the water heater’s temperature setting.
See “3.2 Adjusting the Water Temperature”
on page 10.
4. Troubleshooting
4.1 Solving Basic Problems
If you experience a problem with the water heater, refer to the
following chart for possible remedies. Error codes that appear on
the front panel display are explained in the following section.
For minor problems, resetting the water heater may resolve the
issue. To reset the water heater, press the Reset button on the
front panel.

Troubleshooting 13
4.2 Understanding Error Codes
When an error code appears on the front panel, refer to the following chart for a definition and possible remedy for the situation.
Auto reset Reason Self-diagnostic / Action
E003 Ignition failure Manual reset
E004 False flame detection Auto reset
E012 Flame loss Manual reset
E016 Heat exchanger overheat Manual reset
E030 Abnormal exhaust temperature Manual reset
Auto reset
E046 Abnormal operation: heat exchanger overheating sensor Auto reset
E047 Abnormal operation: exhaust thermostat Auto reset
E060 Abnormal operation: dual venturi limit switch Auto reset
E109 Abnormal operation: fan Manual reset
E110 Exhaust blockage (Condensate blockage) Manual reset
E127 Abnormal operation: APS Manual reset
Auto reset
E407 Abnormal operation: hot water outlet1 thermistor Auto reset
E421 Abnormal operation: cold water inlet1 thermistor Auto reset
E432 Abnormal operation: cold water inlet2 thermistor Auto reset
E434 Abnormal operation: water adjustment valve Manual reset
E438 Abnormal operation: circulation pump Manual
Auto reset
E439 Abnormal operation: flow sensor Manual reset
E441 Abnormal operation: hot water outlet2 thermistor Auto reset
E445 Abnormal operation: mixing valve Manual reset
E515 Abnormal operation: relay feedback (PCB) Manual reset
E517 Abnormal operation: dip switch setting (PCB) Manual reset
E593 Abnormal operation: front panel key Auto reset
E615 Abnormal operation: input and memory (MCU) Manual reset
E736 Abnormal operation: cascade communication Auto reset
E760 Flushing alarm Alarm
E782 Abnormal operation: main panel communication Auto reset
E787 Abnormal operation: reset device Manual reset
Power reset
If the error code is not cleared by resetting the water heater functioning (see “3.4 Resetting the Water Heater”) or if it occurs repeatedly,
call the nearest official Technical Assistance Service (TAS), indicating the number of the error code appearing on the front panel.

14 Guarantee
Guarantee Conditions
Navien’s commercial guarantee covers the correct functioning
of the products manufactured by Navien, in accordance with the
following conditions and time periods:
1. This commercial guarantee is valid for the following periods,
as from the start-up date:
Ɣ2 years for electric and hydraulic elements, pumps, valves,
etc.
Ɣ5 years for heat exchangers.
Ɣ5 years for domestic hot water tanks.
ƔDuring the 2-year period following the start-up date,
Navien will carry out any repairs of original flaws or defects
totally free of charge.
ƔAfter these 2 years have elapsed and until the end of the
guarantee period, labour costs and call-out charges will be
payable by the user.
2. The annual overhaul is not included in the terms of this
guarantee.
3. The start-up and annual overhaul are to be carried out by
personnel authorised by Navien.
4. The commercial guarantee will be null and void in the
following cases:
ƔIf the annual overhaul by personnel authorised by Navien
has not been carried out.
ƔIf the water heater has not been installed in accordance
with the applicable laws and regulations for this type of
appliance.
ƔIf the water heater has not been started up immediately
after its installation, by personnel authorised by Navien.
Failures due to misuses or incorrect installation, use of non-
suitable power or fuel, supply with water with physical or
chemical properties causing incrustation or corrosion, incorrect
handling of the appliance and, in general, for any reason beyond
Navien’s control, are excluded from this guarantee.
This guarantee does not affect the consumer’s rights as
stipulated by law.
Note: Start-up is included in the price of the water heater. The
call-out charge is not included.
Suitable Use
The NPE-AWE/NPE-SWE model water heaters are designed with
all the necessary safety systems. Unsuitable use of the appliance
for a purpose it was not designed for entails risk of damage to
the water heater or property, and even of injury to the user and
other persons.
The NPE-AWE/NPE-SWE model water heaters are designed to
generate heat for domestic hot water and to be connected to
central heating systems. Any use other than the above will be
considered unsuitable use of the water heater. In such cases
the manufacturer/supplier shall not be liable for any damage
caused, and the user will be liable for the damage. Correct use
of the water heater includes reading the user and installation
instructions and all applicable documents, and complying with
the maintenance and inspection conditions.
Everyday Care
Clean the outside of the water heater with a damp cloth with a
little detergent. Do not use abrasive products to clean the water
heater.
Waste Recycling and Disposal
Observe the applicable national regulations and standards
concerning waste disposal.
The water heater
Neither the wall-mounted water heater or its accessories are to
be disposed of with the domestic waste. Ensure the appliance
and its accessories, where applicable, are suitably disposed of.
Packaging
The transport packaging will be disposed of by the specialist
technician who made the installation.
Guarantee

Guarantee 15
Product Fiche (EU regulation No 812/2013)
KD Navien Unit NPE-24AWE NPE-24SWE NPE-32AWE NPE-32SWE
Declared load profile XL XL XXL XXL
Water heating energy efficiency class A A A A
Water heating energy efficiency % 103 106 105 107
Annual electricity consumption kWh41572424
Annual fuel consumption GJ 14 14 18 18
Default temperature setting °C 48.5 48.5 48.5 48.5
Sound power level dB 56 56 58 58
Specific precaution Read the user’s information and installation manual before the application is assembled,
installed or maintained.
ErP Information

Memo

Memo

Memo

Navien Ltd
3000 Cathedral Hill, Guildford, Surrey, GU2 7YB
TEL [phone] www.navien.co.uk
Condensing Water Heater
User’s Information
Manual
20031685B
Getting Service
If your water heater requires service, you have several options for getting service:
Contactan ocial Technical AssistanceService(TAS) at 0844 332 2323 or go to the website
(www.navien.co.uk).
For warranty service, always contactan ocial Technical AssistanceService(TAS) rst.
Contactthe technician or professional who installed your water heater.
ContactaGas Safe Registered engineer.
When you contactan ocial Technical AssistanceService(TAS), please have the following
information at hand:
Model number
Serial number
Date purchased
Installation location and type
Error code, if any appears on the front panel display.
Version: 1.00(Mar.12.2018)