Navien NR-21DU User manual

NR-21DU

Contents
Safety Instructions 3
Included Items 4
Connecting the Extension Cable 5
Attaching the Wall Mounting Bracket 6
Remote Controller 7
LCD Display Icons 8
9Multi Remote Controller System
Turning the Controller On or O
Setting the water temperature
14
Starting Recirculation
15
Entering High Temperature Mode (Commercial Mode) 16
Entering Lock Mode 17
Setting the clock
18
Setting the Recirculation timer
19
Canceling all timer settings
21
24
25Additional features for Cascade systems
28
About errors and icons
30
26
27About scale warning
Basic Troubleshooting and Frequently Asked Questions
Error Code Guide
Safety Instructions
The following safety symbols are used in this manual. Read and follow all safety
instructions in this manual precisely to avoid unsafe operating conditions, re,
explosion, property damage, personal injury, or death. Keep this manual for future
reference.
If you do not follow these instructions exactly, a re
or explosion may result causing property damage,
personal injury or loss of life.
Indicates an imminently
hazardous situation which, if not
avoided, could result in severe
injury or death.
Indicates a potential hazardous
situation which, if not avoided,
may result in injury or death.
Indicates a potentially
hazardous situation that, if not
avoided, could result in property
damage.

Contents
Safety Instructions 3
Included Items 4
Connecting the Extension Cable 5
Attaching the Wall Mounting Bracket 6
Remote Controller 7
LCD Display Icons 8
9Multi Remote Controller System
Turning the Controller On or O
Setting the water temperature
14
Starting Recirculation
15
Entering High Temperature Mode (Commercial Mode) 16
Entering Lock Mode 17
Setting the clock
18
Setting the Recirculation timer
19
Canceling all timer settings
21
24
25Additional features for Cascade systems
28
About errors and icons
30
26
27About scale warning
Basic Troubleshooting and Frequently Asked Questions
Error Code Guide
Safety Instructions
The following safety symbols are used in this manual. Read and follow all safety
instructions in this manual precisely to avoid unsafe operating conditions, re,
explosion, property damage, personal injury, or death. Keep this manual for future
reference.
If you do not follow these instructions exactly, a re
or explosion may result causing property damage,
personal injury or loss of life.
Indicates an imminently
hazardous situation which, if not
avoided, could result in severe
injury or death.
Indicates a potential hazardous
situation which, if not avoided,
may result in injury or death.
Indicates a potentially
hazardous situation that, if not
avoided, could result in property
damage.
3

Included Items
When you open the box, you will nd the following items with the remote controller.
Check the box for each of the following items before installing the remote controller.
User Manual Extension Cable 2 Tapping Screws
Multi Remote Controller Cable
(optional)
Wall Mounting Bracket
Connecting the Extension Cable
1. Connect one end of the extension cable to the
port on the front panel of the water heater.
2. Pass the other end of the extension cable
through the hole in the bracket.
3. Connect the end of the extension cable to the
cable connected to the remote controller.
You can connect up to 2 remote controllers if
necessary.(Optional)
Note
4

Included Items
When you open the box, you will nd the following items with the remote controller.
Check the box for each of the following items before installing the remote controller.
User Manual Extension Cable 2 Tapping Screws
Multi Remote Controller Cable
(optional)
Wall Mounting Bracket
Connecting the Extension Cable
1. Connect one end of the extension cable to the
port on the front panel of the water heater.
2. Pass the other end of the extension cable
through the hole in the bracket.
3. Connect the end of the extension cable to the
cable connected to the remote controller.
You can connect up to 2 remote controllers if
necessary.(Optional)
Note
5

Attaching the Wall Mounting Bracket
1. Ax the bracket securely to the wall by fastening 2 screws to the wall or to the 2 holes in the wall receptacle.
On the wall In the wall receptacle
2. Hang the remote controller on the bracket by aligning the hooks.
Remote Controller
LCD display
Indicates functions and
currentstatus.
LED indicator
Indicates the status of water
heater.
- Green: Normal Mode.
- Red: Error occurred.
Preheat&Timer button
-Access thetimersettings.
-Recirculation ON.
Up button
Increasethetemperature
or value.
Downbutton
Decreasethe temperature
or value.
Lockbutton
Locks the other button
operations.
Power button
Turns the remote controller
OK button
6

Attaching the Wall Mounting Bracket
1. Ax the bracket securely to the wall by fastening 2 screws to the wall or to the 2 holes in the wall receptacle.
On the wall In the wall receptacle
2. Hang the remote controller on the bracket by aligning the hooks.
Remote Controller
LCD display
Indicates functions and
currentstatus.
LED indicator
Indicates the status of water
heater.
- Green: Normal Mode.
- Red: Error occurred.
Preheat&Timer button
-Access thetimersettings.
-Recirculation ON.
Up button
Increasethetemperature
or value.
Downbutton
Decreasethe temperature
or value.
Lockbutton
Locks the other button
operations.
Power button
Turns the remote controller
OK button
7

LCD Display Icons
Timer is set. Recirculation Mode.
Displays the current time. Hot water is in use.
Displays the current set
temperature. Water heater operation is in
progress.
Operations are locked. An error code will appear on the
display.
8
Multi Remote Controller System

9
LCD Display Icons
Timer is set. Recirculation Mode.
Displays the current time. Hot water is in use.
Displays the current set
temperature. Water heater operation is in
progress.
Operations are locked. An error code will appear on the
display.
Multi Remote Controller System
9

10
Multi Remote Controller System
Multi Remote Controller System
10

11
Multi Remote Controller System
Multi Remote Controller System
11

12
Multi Remote Controller System
12
Multi Remote Controller System
9.

13
Multi Remote Controller System
Multi Remote Controller System
9.
13

14
Turning the Controller On or O
To turn the controller on or o, press the Power
button.
When the power is on,
The LCD display turns on.
The LED indicator turns green.
Hot water temperature is displayed.
NoteWhen an error occurs, the LED
indicator turns RED and blinks (except
for Cascade mode).
The backlight stays on for 8 seconds
when a button is pressed.
14
Setting the water temperature
Setting the water temperature above
125 °F (52 °C )can cause instant scalding
or severe burns.
The Range of temperature settings is dierent
depending on the Water Heaters.
Range : 98 ~ 140°F (36~60°C)
NPN Non-Condensing Water Heaters
Range : 98 ~ 140°F (36 ~ 60°C)
NPE-A2/S2 Condensing Water Heaters
Range : 97 ~ 140°F (36 ~ 60°C)
Press the Up or Down button to adjust
the temperature. The temperature
changes by 1°F (0.5°C)
NoteThe settings are automatically saved
For temperature higher than 140 °F (60 °C ),
Check the High Temperature mode in the
next section.
when you do not press any buttons for
5 seconds.
or

15
Turning the Controller On or O
To turn the controller on or o, press the Power
button.
When the power is on,
The LCD display turns on.
The LED indicator turns green.
Hot water temperature is displayed.
NoteWhen an error occurs, the LED
indicator turns RED and blinks (except
for Cascade mode).
The backlight stays on for 8 seconds
when a button is pressed.
Setting the water temperature
Setting the water temperature above
125 °F (52 °C )can cause instant scalding
or severe burns.
The Range of temperature settings is dierent
depending on the Water Heaters.
Range : 98 ~ 140°F (36~60°C)
NPN Non-Condensing Water Heaters
Range : 98 ~ 140°F (36 ~ 60°C)
NPE-A2/S2 Condensing Water Heaters
Range : 97 ~ 140°F (36 ~ 60°C)
Press the Up or Down button to adjust
the temperature. The temperature
changes by 1°F (0.5°C)
NoteThe settings are automatically saved
For temperature higher than 140 °F (60 °C ),
Check the High Temperature mode in the
next section.
when you do not press any buttons for
5 seconds.
or
15

16
Entering High Temperature Mode (Commercial Mode)
1 2
When this mode is available, "HIGH" appears for
3 seconds.
When this mode is unavailable, "LoW" appears
for 3 seconds.
To prevent instant scalding or severe
burns, check the set temperature before
using hot water.
Press the Up button to increase the temperature by
1°F(0.5°C), and press the Down button to decrease
the temperature by 1°F(0.5°C)
Note Commercial Warranty applies when this
mode is used. Refer to the Warranty in
the Operation manual for more details.
Commercial mode is only available for
select models. Refer to the Operation
Manual supplied with the water heater.
10 cse
or
Press and hold the Up and Down button
simultaneously for 10 seconds.
16
Entering Lock Mode
To prevent accidental pressing of the buttons and
to prevent children from adjusting the controller,
you can activate the Temperature Lock Mode.
To activate or deactivate Lock Mode, press the
Lock button for 2 seconds.
When Lock Mode is activated,
• The Lock icon appears on the display.
• All buttons except for Lock button are locked.
Note • Resetting errors or alarms is still
available with Lock Mode activated.
• You can change the settings from the
front panel with Lock Mode activated.

17
Entering High Temperature Mode (Commercial Mode)
1 2
When this mode is available, "HIGH" appears for
3 seconds.
When this mode is unavailable, "LoW" appears
for 3 seconds.
To prevent instant scalding or severe
burns, check the set temperature before
using hot water.
Press the Up button to increase the temperature by
1°F(0.5°C), and press the Down button to decrease
the temperature by 1°F(0.5°C)
Note Commercial Warranty applies when this
mode is used. Refer to the Warranty in
the Operation manual for more details.
Commercial mode is only available for
select models. Refer to the Operation
Manual supplied with the water heater.
10 cse
or
Press and hold the Up and Down button
simultaneously for 10 seconds.
Entering Lock Mode
To prevent accidental pressing of the buttons and
to prevent children from adjusting the controller,
you can activate the Temperature Lock Mode.
To activate or deactivate Lock Mode, press the
Lock button for 2 seconds.
When Lock Mode is activated,
• The Lock icon appears on the display.
• All buttons except for Lock button are locked.
Note • Resetting errors or alarms is still
available with Lock Mode activated.
• You can change the settings from the
front panel with Lock Mode activated.
17

18
Starting Recirculation
During the recirculation,
when NPN Non-condensing water heaters are connected, The preheating icon ashes continuously.
when NPE-A2/S2 condensing water heaters are connected, The preheating icon keeps turning on.
18
Setting the clock
1 2
Press the Timer button for 2 Seconds.
Setting the clock is available only when
NPN Non-condensing water heaters are
connected.
Adjust the minutes by pressing the Up or Down
Button.
Press the OK button to set the minutes.
Note

Starting Recirculation
During the recirculation,
when NPN Non-condensing water heaters are connected, The preheating icon ashes continuously.
when NPE-A2/S2 condensing water heaters are connected, The preheating icon keeps turning on.
Setting the clock
1 2
Press the Timer button for 2 Seconds.
Setting the clock is available only when
NPN Non-condensing water heaters are
connected.
Adjust the minutes by pressing the Up or Down
Button.
Press the OK button to set the minutes.
Note
19

3 4
Once the minutes are set, adjust the hour by
pressing the Up or Down button.
Press the OK button to nish and save the updated
time.
20
Setting the Recirculation timer
1 2
Press the Timer button twice to set the
Recirculation timer.
Reservation Schedule #1 is ready to be set.
Set the recirculation activation time by pressing
the Up or Down button.
Press the OK button to set the deactivation time.
Note The recirculation timer settings are
divided in 30 minute increments.
Note Setting the Recirculation Timer is available
only when NPN Non-condensing water heaters
are connected.
X2