STIEBEL ELTRON DCE 10 Premium Instruction Manual

OPERATION AND INSTALLATION
OPERACIÓN E INSTALACIÓN
Fully electronically controlled electric tankless water heater
Calentador eléctrico de agua sin tanque con control completamente electrónico
» DCE 10 Premium
» DCE 13 Premium
» DCE 15 Premium
Certified to ANSI/UL Std. 499
Conforms to CAN/CSA Std. C22.2 No. 64
Certificación con ANSI/UL Std. 499
Conforme a CAN/CSA Std. C22.2 No.64

2| DCE Premium www.stiebeleltronamericas.com
CONTENTS
QUICK START GUIDE
SPECIAL INFORMATION
OPERATION
1. General information �����������������������������������������5
1.1 Safety instructions����������������������������������������������� 5
1.2 Other symbols in this documentation ����������������������� 5
1.3 Units of measurement ������������������������������������������ 5
2. Safety����������������������������������������������������������5
2.1 Intended use������������������������������������������������������ 5
2.2 General safety instructions ������������������������������������ 5
2.3 Test symbols ������������������������������������������������������ 6
2.4 Licenses / certificates ������������������������������������������� 6
3. Water heater description������������������������������������6
4. Settings and displays ����������������������������������������7
4.1 User interface ���������������������������������������������������� 7
4.2 Display overview������������������������������������������������� 7
4.3 Using the display menus ��������������������������������������� 7
4.4 Recommended settings ��������������������������������������� 11
5. Cleaning, care and maintenance ������������������������� 11
6. Troubleshooting �������������������������������������������� 11
INSTALLATION
7. Safety�������������������������������������������������������� 12
7.1 General safety instructions ����������������������������������� 12
7.2 Instructions, standards and regulations ������������������� 12
8. Water heater description���������������������������������� 12
8.1 Standard delivery����������������������������������������������� 12
8.2 Accessories������������������������������������������������������� 12
9. Preparation ������������������������������������������������� 12
9.1 Installation site�������������������������������������������������� 12
9.2 Minimum clearances������������������������������������������� 13
9.3 Water connections���������������������������������������������� 13
9.4 Permissible water connection materials ������������������� 13
10. Installation�������������������������������������������������� 13
10.1 Standard non-concealed installation ����������������������� 14
10.2 Electrical connection������������������������������������������� 14
11. Commissioning ��������������������������������������������� 15
11.1 Internal anti-scalding protection via jumper slot �������� 15
11.2 Changing power output via the jumper slot; only for
models with selectable power output���������������������� 15
11.3 Initial start-up ��������������������������������������������������� 15
11.4 Operation with preheated water ���������������������������� 16
11.5 Recommissioning ����������������������������������������������� 16
12. Water heater shutdown ����������������������������������� 16
13. Alternative installation methods ������������������������� 16
13.1 Concealed installation, electrical connection from
below�������������������������������������������������������������� 16
13.2 Electrical connection with short power cable ������������ 17
13.3 Concealed installation, electrical connection from
above�������������������������������������������������������������� 17
13.4 Electrical connection from the side, non-concealed
installation ������������������������������������������������������� 17
13.5 Concealed installation, water connections ���������������� 17
14. Service information ���������������������������������������� 18
15. Troubleshooting �������������������������������������������� 19
16. Maintenance ������������������������������������������������ 20
16.1 Draining the water heater ������������������������������������ 20
16.2 Cleaning the filter screen ������������������������������������� 20
17. Specification ������������������������������������������������ 21
17.1 Dimensions and connections��������������������������������� 21
17.2 Wiring diagram ������������������������������������������������� 21
17.3 DHW output������������������������������������������������������ 21
17.4 Application areas/conversion table ������������������������� 22
17.5 Pressure drop ��������������������������������������������������� 22
17.6 Fault conditions ������������������������������������������������� 22
17.7 Data table �������������������������������������������������������� 23
18. Warranty ���������������������������������������������������� 24

QUICK START GUIDE
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 3
QUICK START GUIDE
Before turning on power to the water heater, you MUST flush all air out of
the system, then engage the AE3 safety switch. The unit will NOT operate
until the AE3 safety switch has been engaged.
1 Mount the unit to the wall (see section 10.1, “Standard non-concealed installation”, pg. 14).
2 Hook up water connections (see section 9.3, “Water connections”, pg. 13).
3 Hook up electrical connections, but keep circuit breaker off. (See section 10.2, “Electrical con-
nection”, pg. 14)
≥ 3 min.
12
D0000053277
4 Open and close all connected draw-off valves at least 5 times, for at least 3 minutes total,
until all air has been purged from the pipework and the water heater.
5 Ensure there are no water leaks from any plumbing connections.
D0000073622
6 Engage the AE3 safety switch by firmly pressing the white reset button until it clicks and
fully locks in place (the water heater is delivered with the safety switch disengaged).
7 Turn on power to the water heater at the circuit breaker in the breaker panel.

SPECIAL INFORMATION
4| DCE Premium www.stiebeleltronamericas.com
SPECIAL INFORMATION
- Read this entire manual. Failure to follow all the
guides, instructions and rules could cause personal
injury or property damage. Improper installation,
adjustment, alteration, service and use of this unit
can result in serious injury.
- This unit must be installed by a licensed electrician
and plumber. The installation must comply with
all national, state and local plumbing and electric
codes. Proper installation is the responsibility of the
installer. Failure to comply with the installation and
operating instructions or improper use voids the
warranty.
- Save these instructions for future reference. The
installer should leave these instructions with the
consumer.
- If you have any questions regarding the installation,
use or operation of this water heater, or if you need
any additional installation manuals, please call our
technical service line at 800.582.8423 (USA and Can-
ada only). If you are calling from outside the USA or
Canada, please call USA 413.247.3380 and we will
refer you to a qualified Stiebel Eltron service repre-
sentative in your area.
- The water heater may be used by children aged3
and older and persons with reduced physical, sen-
sory or mental capabilities or a lack of experience
and know-how, provided that they are supervised
or they have been instructed on how to use the
water heater safely and have understood the poten-
tial risks. Children must never play with the water
heater. Children must never clean the water heat-
er or perform user maintenance unless they are
supervised.
- The water heater is suitable for supplying a shower
in many climates (shower operation). If the water
heater is also or exclusively used for shower oper-
ation, the qualified contractor must adjust the tem-
perature setting range to 131 °F (55°C) or less using
the internal anti-scalding protection on the water
heater. When using preheated water, it must be
ensured that the inlet temperature does not exceed
131 °F (55 °C).
- Ensure the water heater can be separated from
the power supply by a circuit breaker that discon-
nects all poles with at least 1/8˝ (3mm) contact
separation.
- The specified voltage must match the power sup-
ply. See the type plate on the right-hand side of the
water heater for full information.
- CAUTION: DO NOT INSTALL IN A BATH ENCLOSURE
OR SHOWER STALL OR CONNECT TO A SALT-REGEN-
ERATED WATER SOFTENER OR A WATER SUPPLY OF
SALT WATER
FOR USE ON AN INDIVIDUAL BRANCH CIRCUIT ONLY
CAUTION: CONNECT ONLY TO A CIRCUIT PROTECTED
BY A CLASS A GROUND FAULT CIRCUIT INTERRUPT-
ER
USE COPPER CONDUCTORS ONLY
USE BONDING CONDUCTOR IN ACCORDANCE WITH
THE CANADIAN ELECTRICAL CODE, PART I
- The water heater must be properly grounded. See
section 17.2, “Wiring diagram”, pg. 21.
- The water heater must be permanently connected
to fixed wiring. For use on an individual branch
circuit only. See section 17.2, “Wiring diagram”, pg.
21.
- Secure the water heater as described in chapter 10,
“Installation”, pg. 13.
- Observe the maximum permissible pressure (See
section 17.7, “Data table”, pg. 23).
- Drain the water heater as described in section 16.1,
“Draining the water heater”, pg. 20.

OPERATION
General information
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 5
OPERATION
1. General information
Chapters "Special information" and "Operation" are intended for
both users and qualified contractors.
Chapter "Installation" is intended for qualified contractors.
Note
Read these instructions carefully before using the water
heater and retain them for future reference.
Pass on the instructions to a new user if required.
1.1 Safety instructions
1.1.1 Structure of safety instructions
!
KEYWORD Type of risk
Here, possible consequences are listed that may result
from failure to observe the safety instructions.
f Steps to prevent the risk are listed.
1.1.2 Symbols, type of risk
Symbol Type of risk
Injury
Electrocution
Burns
(burns, scalding)
1.1.3 Keywords
KEYWORD Meaning
DANGER Failure to observe this information will result in serious
injury or death.
WARNING Failure to observe this information may result in serious
injury or death.
CAUTION Failure to observe this information may result in non-seri-
ous or minor injury.
1.2 Other symbols in this documentation
Note
General information is identified by the adjacent symbol.
f Read these texts carefully.
Symbol Meaning
Material losses
(Water heater damage, consequential losses and environ-
mental pollution)
Appliance disposal
f This symbol indicates that you have to do something. The ac-
tion you need to take is described step by step.
1.3 Units of measurement
Note
All measurements are given in inches (millimeters) unless
otherwise stated.
2. Safety
2.1 Intended use
This water heater is suitable for heating domestic hot water or
for reheating preheated water. The water heater can supply one
or more draw-off points.
Water will not be reheated if the maximum inlet temperature for
reheating is exceeded.
The water heater is intended for domestic use. It can be used
safely by untrained persons. The water heater can also be used
in non-domestic environments, e.g. in small businesses, as long
as it is used in the same way.
Any other use beyond that described shall be deemed inappro-
priate. Observation of these instructions and of the instructions
for any accessories used is also part of the correct use of this
water heater.
2.2 General safety instructions
DANGER Burns
Water temperatures over 125 °F (52 °C) can cause se-
vere burns instantly or death from scalding. A hot water
scalding potential exists if the thermostat on the water
heater is set too high. Households with small children,
disabled or elderly persons may require that the thermo-
stat be set at 113 °F (45 °C) or lower to prevent possible
injury from hot water.
CAUTION Burns
If operating with preheated water, e.g.from a solar
thermal system, the DHW temperature may vary from
the selected set temperature.
CAUTION Burns
During operation, the tap can reach temperatures up to
158 °F (70 °C).
There is a risk of scalding at outlet temperatures in ex-
cess of 109 °F (43 °C).
!
!

OPERATION
Water heater description
6| DCE Premium www.stiebeleltronamericas.com
!
DANGER Injury
Please read and follow these instructions. Failure to fol-
low these instructions could result in serious personal
injury or death.
!
CAUTION: DO NOT INSTALL IN A BATH ENCLOSURE OR
SHOWER STALL OR CONNECT TO A SALT-REGENERATED
WATER SOFTENER OR A WATER SUPPLY OF SALT
WATER
FOR USE ON AN INDIVIDUAL BRANCH CIRCUIT ONLY
CAUTION: CONNECT ONLY TO A CIRCUIT PROTECTED
BY A CLASS A GROUND FAULT CIRCUIT INTERRUPTER
USE COPPER CONDUCTORS ONLY
USE BONDING CONDUCTOR IN ACCORDANCE WITH THE
CANADIAN ELECTRICAL CODE, PART I
DANGER Electrocution
Before proceeding with any installation, adjustment,
alteration, or service of this appliance, all circuit break-
ers and disconnect switches servicing the appliance
must be turned off. Failure to do so could result in
serious personal injury or death.
WARNING Electrocution
Never remove or reinstall the water heater’s cover
unless the electricity servicing the unit is turned off.
Failure to do so could result in personal injury or death.
!
DAMAGE TO THE WATER HEATER AND THE ENVIRON-
MENT:
The water heater must be installed by a licensed elec-
trician and plumber. The installation must comply with
all national, state and local plumbing and electric codes.
Service of the water heater must be performed by qual-
ified service technicians.
!
DAMAGE TO THE WATER HEATER AND THE ENVIRON-
MENT:
Supply this appliance only from a grounded system. A
green terminal (or a wire connector marked “G”, “GR”,
“GROUND”, OR “GROUNDING”) is provided for wiring the
appliance. To reduce the risk of electric shock, connect
this terminal or connector to the grounding terminal of
the electric service or supply panel with a continuous
copper wire in accordance with the electrical installa-
tion code.
!
WARNING Injury
The appliance may be used by children aged3 and older
and persons with reduced physical, sensory or mental
capabilities or a lack of experience and know-how, pro-
vided that they are supervised or they have been in-
structed on how to use the appliance safely and have
understood the potential risks. Children must never play
with the appliance. Children must never clean the ap-
pliance or perform user maintenance unless they are
supervised.
Note
When mounting the water heater to the wall, counter-
sunk screws must be used in order to maintain the IP 24
rating. See section 10.1.4, “Mounting the water heater”,
pg. 14.
Where children or persons with limited physical, sensory or men-
tal abilities are allowed to use this water heater, we recommend
a permanent temperature limit. The following limitation options
are available:
- User adjustable: Temperature limit (childproofing)
- Qualified contractor adjustable: "Internal anti-scalding
protection"
!
Material losses
The user should protect the water heater against frost.
2.3 Test symbols
See type plate on the water heater.
2.4 Licenses / certificates
- UL (USA) Std. 499
- CSA (Canada) Std. C22.2 No. 64
3. Water heater description
The water heater switches on automatically as soon as you open
the hot water valve at the tap. When you close the tap, the water
heater switches off again automatically.
The water heater heats water as it flows through it. The DHW out-
let temperature can be variably adjusted. From a certain flow rate,
the control unit regulates the correct heating output, subject to
the temperature selected and the current cold water temperature.
The compact instantaneous water heater with full electronic con-
trol and automatic output matching maintains a consistent outlet
temperature. The water is heated precisely to the selected tem-
perature by the electronic control unit with motorized valve. This
occurs regardless of the inlet temperature.
If the water heater is operated with preheated water and the inlet
temperature exceeds the selected set temperature, the inlet tem-
perature will be displayed on the second row of the screen and
will flash. The water is not heated further.
The compact instantaneous water heater with full electronic con-
trol allows you to save different temperatures and apply them
quickly. The water heater is equipped with functions to perma-
nently limit the temperature (childproofing). As soon as water
flows through the water heater, or you make a change at the user
interface, the backlight switches on automatically. The backlight
switches off automatically if no changes are made for 30seconds,
or 5seconds after water stops being drawn off.
DHW temperature
The DHW outlet temperature can be variably adjusted, with a
range from 68–140 °F (20–60 °C). The selected temperature is dis-
played.

OPERATION
Settings and displays
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 7
Heating system
The Direct Coil™heating system is enclosed within a pressure-test-
ed plastic jacket. The heating system with its nichrome heating
element is suitable for hard and soft water areas and is largely
insusceptible to scale build-up. The Direct Coil™heating system
ensures rapid, accurate, and efficient DHW production.
Note
The water heater is equipped with an air detector that
largely prevents damage to the heating system. If, during
operation, air is drawn into the water heater, the water
heater shuts down the heating output for one minute to
protect the heating system.
4. Settings and displays
4.1 User interface
D0000073619
2
3
1
8
5
6
7
4
1 Control knob
2 Operating LED (flashes when output limit reached)
3 Temperature memory keys
4 Backlit display
5 Main display | info display | parameter display
6 Segment display [10–100%]
7 Second row of screen
8 “i” button to retrieve information and select menus
4.2 Display overview
1
2
3
4
678
9
10
1112
13
14
5
1 Primary digit display
2 Power capacity status
3 Display-lock indicator
4 Error code symbol
5 Secondary digit display
6 Tmax indicator
7 Savings statistics indicator
8 x1000 secondary display value
9 Gallons secondary display unit
10 kWh secondary display unit
11 Liters or liters per minute secondary display unit
12 Gallons per minute secondary display unit
13 Temperature unit for secondary display
14 Temperature unit for primary display
4.3 Using the display menus
The DCE Premium features an interactive display that allows for
user customization to increase the level of comfort and conve-
nience.
The menu structure is designed in an intuitive, linear way to make
it as navigable as possible.
User input
Information button (pressing or holding this
button performs different functions)
Preset 1 button (pressing or holding this but-
ton performs different functions)
Preset 2 button (pressing or holding this but-
ton performs different functions)
Control knob (turn knob to change settings)

OPERATION
Settings and displays
8| DCE Premium www.stiebeleltronamericas.com
The DCE Premium features a primary and secondary display area
allowing for multiple parameters or information to be displayed.
The DCE Premium is capable of displaying the current flow rate of
the water passing through the water heater, as well as calculating
the accumulated cost savings of having a tankless water heater
compared to a tank-type water heater.
For the name of each display element on the DCE Premium, consult
section 4.2, “Display overview”, pg. 7.
4.3.1 Base display
The DCE Premium base display displays the current setpoint tem-
perature in your preferred temperature unit in the top half of the
display.
The bar below the temperature shows the current fraction of total
capacity that the water heater is running at. As the hot water de-
mand fluctuates, the power capacity status will change to show
between 0 and 10 segments. The display below shows that the
water heater is operating at 40% of capacity.
The bottom half of the display shows the current flow rate through
the unit in either liters per minute (l/min) or gallons per minute
(gpm).
All other menus will revert back to the base display either after a
15 second period of time without user input, or after a 5 second
hold of the Information button.
Changing the setpoint temperature
Temperature settings
Range Increment Range Increment
68–140 °F 1 °F 20–60 °C 0.5 °C
The setpoint temperature can be set between 68 °F (20 °C) and
140 °F (60 °C).
The setpoint can be increased by turning the control knob clock-
wise, and decreased by turning it counter-clockwise. The water
heater can be deactivated while still powered by turning the con-
trol knob counter-clockwise, past the 68 °F (20 °C) setting.
4.3.2 Information menu
The information menu structure displays additional information
for the user. The information menu is accessed by pressing the
Information button while at the base display.
Accumulated cost savings display
If the Information button is pressed while the display is showing
the base display, the display will advance to the accumulated cost
savings display.
The accumulated cost savings display will display “I1” in the top
half of the display, and the bottom half of the display will alternate
between “Cur” and the accumulated savings of the water heater.
The accumulated cost savings updates daily, and shows the esti-
mated savings for the user compared to an installation where a
50-gallon tank-type water heater was used.
Note
The energy saving values are calculated starting from
the last reset.
This savings estimate is based on the users electricity cost. For
the most accurate estimate, the electricity cost per kWh should
be set in the electricity cost parameter setting menu. For infor-
mation on how to do this, see section “Electricity cost parameter
setting”, pg. 9.
Pressing the Information button will advance back to the base
display. The display will also revert back to the base display if no
user input is detected for 15 seconds.
4.3.3 Parameters menu
The parameters menu allows multiple settings on the DCE Pre-
mium to be altered. The parameters menu can be accessed by
holding the Information button for 5 seconds.
Tmax parameter setting
The first parameter menu sets the value for Tmax. The value of
Tmax acts as a high temperature limiter. If the Tmax value is set, the
setpoint of the water heater cannot be set above the Tmax value.
This feature is useful in scenarios where scalding from hot water
is a real possibility.
At the Tmax setting menu, the temperature value will flash, in-
dicating that the value can be changed by rotating the control
knob. The Tmax value can be increased by turning the control knob
clockwise, and decreased by turning it counter-clockwise. The
Tmax value can be deactivated by turning the control knob count-
er-clockwise, past the 68 °F (20 °C) setting. The display will read
“Off” if Tmax is inactive.
If the Tmax symbol is visible at the base display, then the Tmax func-
tion is active and limiting the maximum allowable temperature.

OPERATION
Settings and displays
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 9
Pressing the Information button once while at this menu will move
the display onto the temperature units parameter setting.
Temperature units parameter setting
The DCE Premium is capable of displaying temperature in either
Celsius or Fahrenheit.
The current unit will be shown and the secondary display value
will be flashing to indicate that the value can be changed. Rotate
the control knob to change the value between Celsius and Fahr-
enheit.
Pressing the Information button once while at this menu will move
the display onto the volume units parameter setting.
Volume units parameter setting
The DCE Premium is capable of displaying volume flow in either
liters per minute (l/min) or gallons per minute (gpm).
The current volume unit will be displayed and the value will be
flashing to indicate that it can be changed. Rotate the control knob
to change the value between liters and gallons.
Pressing the Information button once while at this menu will ad-
vance the display to the electricity cost parameter setting.
Electricity cost parameter setting
The DCE Premium has a built-in feature where it calculates the
energy savings of the unit when compared to the average energy
use of a tank-type water heater. In order for this feature to be
accurate, the cost per kWh of electricity must be programmed
into the software.
The secondary display will be flashing to indicate that the value
can be changed by rotating the control knob. Consult your elec-
tricity bill to determine the cost of electricity per kWh.
Pressing the Information button once while at this menu will ad-
vance the display to the display-lock parameter setting.
Display-lock parameter setting
The display can be locked to prevent easy alteration of the tem-
perature setpoint. This menu will flash, indicating that the value
can be changed by rotating the control knob. While “Off” is dis-
played, the lock is not active. The lock is active when the display
reads “On”.
If the display-lock parameter is set to “On” and the user either
holds the Information button for 5 seconds or lets the display time
out for 15 seconds, the display-lock will become active.
With the display-lock active, a lock will appear on the base display,
and no parameters can be changed. In order to disable the lock,
hold the Information button for 12 seconds. The lock will then
disappear and all parameters can be changed again.
Pressing the Information button once while at the display-lock
parameter setting menu will move the display onto the factory
setting reset parameter menu.
Factory setting reset parameter
The temperature setpoint, preset values, temperature, & volume
units can all be reset to their factory settings.
The display will be flashing to indicate that the value can be
changed by rotating the control knob. When the value is set to
“On”, the reset must be confirmed by holding both Button 1 and
Button 2 simultaneously for 5 seconds.
Pressing the Information button once will advance the display to
the accumulated savings reset parameter menu.
Accumulated savings reset parameter
Much like the factory setting reset parameter, the calculated ac-
cumulated savings value can be reset to zero.

OPERATION
Settings and displays
10 | DCE Premium www.stiebeleltronamericas.com
The display will be flashing to indicate that the value can be
changed by rotating the control knob. When the value is set to
“On”, the reset must be confirmed by holding both Button 1 and
Button 2 simultaneously for 5 seconds.
Pressing the Information button once will advance the display to
the display backlight time-out parameter.
Display backlight time-out parameter
The backlight of the display can be set to be always on, or set to an
automatic mode that deactivates when no user input is detected
for 15 seconds.
The entire display and backlight will be flashing to indicate that
the value can be changed by rotating the control knob. When
the value is set to “On”, the backlight will always be on. When
the value is set to “Auto”, it will automatically deactivate after 15
seconds of inactivity.
Pressing the Information button once while at this menu will ad-
vance the display to the backlight display brightness parameter
menu.
Backlight display brightness parameter
The brightness of the display backlight can be adjusted to two
different parameters. A high and low setting allows for user cus-
tomization depending on the light conditions in the installation
location.
The power capacity status bar indicates the brightness setting.
A full capacity bar indicates that the brightness is at the high
setting. Two capacity bar segments indicates that the brightness
is at the low setting.
Pressing the Information button once while at this menu will ad-
vance the display back to the Tmax parameter setting page, labeled
“P1”.
4.3.4 Temperature preset options
The DCE Premium features two temperature preset settings to
allow quickly accessible setpoints. Button 1 and Button 2 are ca-
pable of each storing an independent setpoint value.
Changing setpoint temperature to preset values
While the display is at the base display, the user can press either
Button 1 or Button 2 to change the setpoint to the button’s stored
temperature value.
Press
When the button is pressed, the setpoint value will change to
whatever value was stored up to that point.
Changing the preset values
The preset values can be changed from the default setpoint values.
Hold 3
seconds
To change the value of either preset 1 or preset 2, first rotate the
control knob to the temperature that you want to set the preset
value. Then hold the preset button for 3 seconds. The display will
flash to indicate that the preset has been changed successfully.
4.3.5 Returning to the base display
While navigating the display and on any menu other than the base
display, holding the Information button for 5 seconds will return
the display to the base display. Additionally, the display will revert
to the base display after a 15 second period with no user input.
4.3.6 Error menu
If the DCE Premium encounters an error, a wrench will illuminate
in the bottom left of the display.
Hold 5
seconds

OPERATION
Cleaning, care and maintenance
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 11
While the wrench is showing, press and hold the Information
button for five seconds to advance the display to the error display
page.
Consult section 15, “Troubleshooting”, pg. 19 for information
on how to interpret the reported error code.
4.4 Recommended settings
Your electric tankless water heater offers maximum convenience
and accuracy when providing DHW. Should you need to operate
the water heater with a thermostatic valve, we recommend that
you:
f Adjust the set temperature on the water heater to over 122 °F
(50°C). Then set the required set temperature on the thermo-
static valve.
Saving energy
The following recommended settings will result in the lowest en-
ergy consumption:
- 100 °F (38 °C) for hand washbasins, showers, baths
- 131°F (55 °C) for kitchen sinks
Internal anti-scalding protection (qualified contractors)
If required, the qualified contractor can set a permanent tempera-
ture limit, for example in nurseries, hospitals,etc.
When supplying a shower, the water heater temperature setting
range must be adjusted by the qualified contractor to 131 °F (55 °C)
or less.
For full information, see section 11.1, “Internal anti-scalding pro-
tection via jumper slot”, pg. 15.
Recommended setting for operation with a thermostatic valve
and water preheated by solar energy
f Set the temperature at the water heater to the maximum
temperature.
Following an interruption to the water supply
!
Material losses
To ensure that the Direct Coil™heating system is not dam-
aged following an interruption to the water supply, the
water heater must be restarted by taking the following
steps.
f Shut off power to the unit at the breaker panel by
making sure that connected circuit breakers are
“OFF” to avoid any danger of electric shock.
f Open and close the tap at least five times for three
minutes total, until the water heater and its up-
stream cold water inlet line are free of air.
f Switch the power back ON at the breaker.
5. Cleaning, care and maintenance
f Never use abrasive or corrosive cleaning agents. A damp
cloth is sufficient for cleaning the water heater.
f Check the taps regularly. Limescale deposits at the tap out-
lets can be removed using commercially available descaling
agents.
6. Troubleshooting
Problem Cause Solution
The water heater will not
start despite the DHW
valve being fully open
There is no power Check to ensure circuit
breaker in breaker panel
hasn’t tripped. Reset if
necessary
The white AE3 safety
switch has not been en-
gaged during initial start-
up. Activate if necessary
(See section 11.3.1, “Initial
AE3 safety switch activa-
tion”, pg. 15). If the AE3
switch has tripped after
initial installation, contact
a qualified contractor to
fix the cause
The aerator in the tap
or the shower head is
scaled up or dirty
Clean and/or descale the
aerator or shower head
The water supply has
been interrupted
Vent the water heater and
the cold water inlet line
When hot water is being
drawn off, cold water
flows for a short period
The air detector de-
tects air in the water. It
switches off the heat-
ing output briefly
The water heater restarts
automatically after 1min-
ute
The required temperature
cannot be set
Internal anti-scalding
protection is activated
The internal anti-scalding
protection can only be
adjusted by qualified con-
tractors
Note
The information shown on the programming unit and the
selected settings are retained following a power failure
(with the exception of the time).
If you cannot remedy the problem, contact your qualified con-
tractor. To facilitate and speed up your inquiry, please provide the
serial number from the type plate (000000-0000-000000).
Nr.: 000000-0000-00000
D0000073621

INSTALLATION
Safety
12 | DCE Premium www.stiebeleltronamericas.com
INSTALLATION
7. Safety
Only a qualified contractor should carry out installation, commis-
sioning, maintenance and repair of the water heater.
7.1 General safety instructions
We guarantee trouble-free function and operational reliability
only if original accessories and spare parts intended for the water
heater are used.
!
Material losses
Observe the maximum inlet temperature. Higher tem-
peratures may damage the water heater. You can limit
the maximum inlet temperature by installing a central
thermostatic valve.
WARNING Electrocution
This water heater contains capacitors which are dis-
charged when disconnected from the power supply. The
capacitor discharge voltage may briefly exceed60VDC.
7.2 Instructions, standards and regulations
Note
Observe all applicable national and regional regulations
and instructions.
- The IP24 (splash-proof) protection rating can only be en-
sured with a correctly fitted cable grommet, and by using
countersunk screws with a diameter of 4.5 mm, max. diame-
ter of the screw-head 9 mm.
- The electrical resistivity of the water must not fall below that
stated on the type plate. In a linked water network, factor
in the lowest electrical resistivity of the water. Your water
supply utility will advise you of the electrical resistivity or
conductivity of the water in your area.
8. Water heater description
8.1 Standard delivery
The following are delivered with the water heater:
- Cable grommet
- Filter screen, factory installed in cold water inlet
- Jumper for anti-scalding protection, attached
- Jumper for power output selection, attached
- Jumper, spare
- Plug for electrical connection, non-concealed installation,
bottom center
8.2 Accessories
Installation kit for concealed water connections
The following accessories are required for concealed water con-
nection installations (not supplied, available as a kit, part number
200017 – IW-Kit LA):
- 2 x plugs to seal the apertures in the water heater back panel
- 2 x 45° twin connectors
- Filter screen with sealed edge for installation on the 45°twin
connector
- Flat gasket
9. Preparation
9.1 Installation site
!
Material losses
Install the water heater in a room that is free from the
risk of frost.
f Always install the water heater vertically with plumbing fit-
tings pointing downward.
The water heater is suitable for supplying multiple fixtures, with
installation location either below or above connected fixtures. The
water heater should be positioned as close as possible to major
draw points in order to minimize pipe runs.
Taps
Do not use open vented or non-pressurized taps.
Typical residential installation
1
2
1 Cold water inlet
2 DHW outlet
Note
f Install the water heater flush to the wall. The wall
must have sufficient load bearing capacity.

INSTALLATION
Installation
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 13
9.2 Minimum clearances
(≥50)≥2˝ (≥50)≥2˝
(≥50)≥2˝
(≥100 mm)≥4˝
D0000079442
f Maintain the minimum clearances to ensure trouble-free op-
eration of the water heater and facilitate maintenance work.
9.3 Water connections
!
CAUTION: DO NOT INSTALL IN A BATH ENCLOSURE OR
SHOWER STALL OR CONNECT TO A SALT-REGENERATED
WATER SOFTENER OR A WATER SUPPLY OF SALT
WATER
FOR USE ON AN INDIVIDUAL BRANCH CIRCUIT ONLY
CAUTION: CONNECT ONLY TO A CIRCUIT PROTECTED
BY A CLASS A GROUND FAULT CIRCUIT INTERRUPTER
USE COPPER CONDUCTORS ONLY
USE BONDING CONDUCTOR IN ACCORDANCE WITH THE
CANADIAN ELECTRICAL CODE, PART I
!
Material losses
Carry out all water connection and installation work in
accordance with regulations.
!
Material losses
Excessive heat from soldering on copper pipes near the
DCE may cause damage to the unit or the plastic filter
screen located in the cold water inlet.
NOTICE
The cold water connection to the unit MUST be discon-
nected periodically in order to clean the filter screen.
It is required to use water connections that are easily
detachable such as braided steel flex connectors.
NOTICE
Hard water or water with a high mineral count may dam-
age the unit. Damage to the unit caused by scale or a high
mineral count is not covered under the warranty.
NOTICE
Tankless water heaters such as the DCE are not required
to be equipped with a temperature and pressure relief
valve (T&P). If the local inspector will not pass the in-
stallation without a T&P, it should be installed on the hot
water outlet side of the unit.
f Make certain that the cold water supply line has been flushed
to remove any scale and dirt.
f The DCE unit has a built in filter screen located in the cold
water inlet that should be cleaned from time to time. Clean
screen and put the screen back into their original position.
See section 16.2, “Cleaning the filter screen”, pg. 20
The cold water connection (inlet) is on the right side of the unit,
and the hot water connection (outlet) is on the left side of the
unit.
9.4 Permissible water connection materials
f The DCE’s hot water outlet (left) is designed for connection to
copper tubing, PEX tubing, or a braided stainless steel hose
with a ½˝ NPT female tapered thread.
f The plumbing on the cold water inlet side (right) needs to be
such that it can easily be removed to allow access to the inlet
filter screen. The easiest way to achieve this is to use a braid-
ed steel flex connector with a ½˝ female NPT connection.
f If soldering near the unit is necessary, please direct the
flame away from the housing of the unit in order to avoid
damage.
f When all plumbing work is completed, check for leaks and
damage to the plastic filter screen. Take corrective action be-
fore proceeding.
!
Material losses
If plastic pipework systems are used, take into account
the maximum inlet temperature and the maximum per-
missible pressure.
9.4.1 Flow rate
f Ensure that the minimum activation flow rate for switching
on the water heater is met: 0.264 gal (1.0 l/min).
f If the required minimum activation flow rate is not met when
the draw-off valve is fully opened, increase the water line
pressure.
f The minimum incoming cold water supply line pressure must
be at least 26.1 psi (1.8 bar) or higher.
10. Installation
Factory settings DCE 10
Premium
DCE 13
Premium
DCE 15
Premium
Internal anti-scalding protection
in °F (°C)
140 (60) 140 (60) 140 (60)
Connected load in kW @ 208V 7.2 11.8 10.7
@ 220V 8.0 13.2 12.0
@ 240V 9.6 14.4
Standard installation DCE 10
Premium
DCE 13
Premium
DCE 15
Premium
Electrical connection from below,
non-concealed installation
x x x
Water connection, non-concealed
installation
x x x
For further installation options, including concealed in-wall elec-
trical and water connection options, see chapter 13, “Alternative
installation methods”, pg. 16.

INSTALLATION
Installation
14 | DCE Premium www.stiebeleltronamericas.com
10.1 Standard non-concealed installation
10.1.1 Removing the cover
D0000073641
f Open the water heater by undoing the screw and lifting up
the cover.
10.1.2 Preparing the power cable
B
A
D0000077179
f Prepare the power cable.
Position for non-concealed
installation
Dimension A Dimension B
Bottom, center 1½˝ (30 mm)4¾˝ (120 mm)
Bottom, left side of water heater ½˝ (20 mm)3½˝ (90 mm)
Bottom, right side of water heater ½˝ (20 mm)3½˝ (90 mm)
Top, right side of water heater ½˝ (20 mm) 31/8˝ (80 mm)
Position for concealed instal-
lation
Dimension A Dimension B
Bottom ½˝ (20 mm)3½˝ (90 mm)
Top ½˝ (20 mm) 31/8˝ (80 mm)
10.1.3 Preparation
f Cut a hole in the cable grommet to fit the selected connecting
cable. Fit the cable grommet.
10.1.4 Mounting the water heater
f Mark the 4drill holes, referencing their position on the water
heater rear cover.
f Drill the holes and secure the water heater using suitable
fixing materials (screws and wall anchors are not part of the
standard delivery): Countersunk screw, Ø4.5mm, max. di-
ameter of screw-head 9mm.
D0000073844
f Connect braided steel flex connectors (recommended,
not supplied) or other pipework to the twin ½˝ NPT male
connectors.
f Open the shut-off valve in the cold water inlet line.
10.2 Electrical connection
WARNING Electrocution
Before beginning any work on the electric instal-
lation, be sure that main breaker panel switches
are “Off” to avoid any danger of electric shock. All
mounting and plumbing must be completed before
proceeding with electrical hook-up. Where required
by local, state or national electrical codes the circuits
should be equipped with a “ground fault interrupter.”
The unit must be properly grounded in accordance
with state and local codes, or in absence of such
codes, in accordance with national electric code or the
Canadian electric code. Failure to electrically ground
the product could result in serious personal injury or
death.
WARNING Electrocution
The connection to the power supply is only permissible
as a permanent connection in conjunction with the re-
movable cable grommet. Ensure the water heater can
be separated from the power supply by an isolator that
disconnects all poles with at least 1/8˝(3mm) contact
separation.
!
CAUTION: DO NOT INSTALL IN A BATH ENCLOSURE OR
SHOWER STALL OR CONNECT TO A SALT-REGENERATED
WATER SOFTENER OR A WATER SUPPLY OF SALT
WATER
FOR USE ON AN INDIVIDUAL BRANCH CIRCUIT ONLY
CAUTION: CONNECT ONLY TO A CIRCUIT PROTECTED
BY A CLASS A GROUND FAULT CIRCUIT INTERRUPTER
USE COPPER CONDUCTORS ONLY
USE BONDING CONDUCTOR IN ACCORDANCE WITH THE
CANADIAN ELECTRICAL CODE, PART I
!
Supply this appliance only from a grounded system. A
green terminal (or a wire connector marked “G”, “GR”,
“GROUND”, OR “GROUNDING”) is provided for wiring
the appliance. To reduce the risk of electric shock,
connect this terminal or connector to the grounding
terminal of the electric service or supply panel with a
continuous copper wire in accordance with the electri-
cal installation code.
!
Material losses
Observe the type plate. The specified rated voltage must
match the supply line voltage.
!
Material losses
The DCE 13 Premium must only be connected to a 208V or
220V electrical supply. Connecting the DCE 13 Premium
to a 240V electrical supply will permanently damage the
unit and void the factory warranty.

INSTALLATION
Commissioning
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 15
f Push the power cable through the cable grommet.
f Connect the power cable to the wiring block (see section
17.2, “Wiring diagram”, pg. 21).
11. Commissioning
11.1 Internal anti-scalding protection via jumper
slot
For increased safety, the qualified contractor can set an internal
anti-scalding temperature limit via the “Tmax” jumper. The an-
ti-scalding protection feature limits the maximum output tem-
perature of the water heater. This feature overrides the tempera-
ture adjustment display on the front cover (both the temperature
selection and temperature limit via software functions). A user
can still make temperature adjustments below the anti-scalding
limit using the display, however, any temperature selected that
is higher than the Tmax limit set will be ignored, and the output
temperature will be limited to the Tmax value.
43°C | 109°F
50°C | 122°F
55°C | 131°F
60°C | 140°F
D0000073624
Jumper position Description
43°C | 109°F Forexample in nurseries, hospitals, etc.
50°C | 122°F Typical DHW
55°C | 131°F Max. for shower operation
60°C | 140°F Factory setting (full temperature range)
No jumper Limit 43°C | 109°F
f Install the jumper in the required position on the “Tmax” pin
strip.
CAUTION Burns
If the water supplied to the appliance is preheated, the
internal anti-scalding protection and the user-adjustable
temperature limit may be exceeded.
In such cases, limit the temperature with an upstream
central thermostatic valve.
11.2 Changing power output via the jumper slot;
only for models with selectable power output
DCE 10 and 15 Premium feature selectable power output. If you
select a value other than the factory default setting, you will need
to reposition the jumper.
1
2
D0000082938
f Install the jumper in the required position on the “Pmax” pin
strip.
Jumper position Power output
DCE 10 Premium
Power output
DCE 15 Premium
1 [low] @ 208V 5.4kW 9.0kW
@ 220V 6.0kW 10.0kW
@ 240V 7.2kW 12.0kW
2 [high] @ 208V 7.2kW 10.7kW
factory default @ 220V 8.0kW 12.0kW
@ 240V 9.6kW 14.4kW
No jumper @ 208V 5.4kW 9.0kW
[low] @ 220V 6.0kW 10.0kW
@ 240V 7.2kW 12.0kW
f Mark the selected power output on the type plate. Use a ball-
point pen to do this.
11.3 Initial start-up
Note
During initial start-up, you MUST engage the AE3 safe-
ty switch by depressing the white reset button before
supplying power to the water heater. The unit will NOT
operate until the safety switch has been engaged.
≥ 3 min.
12
D0000053277
f Open and close all connected draw-off valves at least five
times total. Let water run for at least three minutes, until all
air has been purged from the pipework and the water heater.
f Ensure there are no water leaks from any plumbing
connections.
11.3.1 Initial AE3 safety switch activation
D0000073622
f Engage the AE3 safety switch by firmly pressing the white
reset button until it clicks and fully locks in place (the water
heater is delivered with the safety switch disengaged).

INSTALLATION
Water heater shutdown
16 | DCE Premium www.stiebeleltronamericas.com
D0000082937
f Connect the programming unit connecting cable plug to the
PCB.
Note
It is essential to plug the connecting cable from the
programming unit into the PCB before switching on the
power. Otherwise, the programming unit will not func-
tion.
D0000073642
f Hook the water heater cover into the water heater back panel
at the top rear. Pivot the water heater cover downwards.
Check that the water heater cover is securely seated at both
top and bottom.
f Secure the water heater cover with the screw.
f Remove the protective film from the user interface.
D0000053281
f Switch on the power supply.
f Ensure that the programming unit is functioning correctly.
11.3.2 Water heater handover
f Explain the water heater functions to users and familiarize
them with how it works.
f Make the user aware of potential dangers, especially the risk
of scalding.
f Hand over the instructions.
11.4 Operation with preheated water
You can limit the maximum inlet temperature by installing a cen-
tral thermostatic valve.
Use a thermostatic valve for central premixing, for example when
operating an instantaneous water heater with preheated water.
For use in shower operation, the valve must be set to a maximum
of 131 °F (55 °C).
11.5 Recommissioning
!
Material losses
To ensure that the Direct Coil™heating system is not dam-
aged following an interruption to the water supply, the
water heater must be restarted by taking the following
steps.
f Shut off power to the unit at the breaker panel by
making sure that connected circuit breakers are
“OFF” to avoid any danger of electric shock.
f Open and close the tap at least five times for three
minutes total, until the water heater and its up-
stream cold water inlet line are free of air.
f Switch the power back ON at the breaker panel.
12. Water heater shutdown
f Shut off power to the unit at the breaker panel by making
sure that connected circuit breakers are “OFF” to avoid any
danger of electric shock.
f Drain the water heater (see section 16.1, “Draining the water
heater”, pg. 20).
13. Alternative installation methods
WARNING Electrocution
Before performing any work on the appliance, discon-
nect all poles from the power supply.
13.1 Concealed installation, electrical connection
from below
D0000079465
1
1 Cable grommet
f Break out the required aperture in the back panel for the
power cable (for positions, see section 17.1, “Dimensions and
connections”, pg. 21). De-burr any sharp edges with a file.
f Cut a hole in the cable grommet to fit the selected connecting
cable. Fit the cable grommet.
f Install the water heater and connect the power cable to
the wiring block as described in section 10.1, “Standard
non-concealed installation”, pg. 14.
f Seal the factory-fitted cable grommet with the plug included
in the standard delivery.

INSTALLATION
Alternative installation methods
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 17
13.2 Electrical connection with short power cable
If the power cable is not quite long enough, you can install the
wiring block closer to the aperture in the water heater.
D0000073648
1
1 Cable grommet
f Reposition the wiring block from the top to the bottom. To do
so, unclip the wiring block by pushing it firmly to the left and
pulling it forwards. Clip the wiring block in at the bottom by
pushing it inwards and leftwards until it clicks into place.
13.3 Concealed installation, electrical connection
from above
D0000073620
2
1
1 Cable grommet
2 Cable routing
f Break out the required aperture in the back panel for the
power cable (for positions, see section 17.1, “Dimensions and
connections”, pg. 21). De-burr any sharp edges with a file.
f Cut a hole in the cable grommet to fit the selected connecting
cable. Fit the cable grommet.
f Reposition the wiring block from the bottom to the top. To do
so, unclip the wiring block by pushing it firmly to the left and
pulling it forwards. Turn the wiring block with connecting ca-
bles 180° clockwise. Lay the internal wiring under the cable
guide. Clip the wiring block in by pushing it inwards and to
the left until it clicks into place.
f Install the water heater and connect the power cable to the
wiring block as described in section 17.2, “Wiring diagram”,
pg. 21.
f Seal the factory-fitted cable grommet with the plug included
in the standard delivery.
13.4 Electrical connection from the side, non-
concealed installation
f Cut and break out the required aperture in the water heater
back panel and water heater cover for the power cable (for
positions, see section 17.1, “Dimensions and connections”,
pg. 21). De-burr any sharp edges with a file.
f Install the water heater and connect the power cable to
the wiring block as described in section 10.1, “Standard
non-concealed installation”, pg. 14.
f Seal the factory-fitted cable grommet with the plug included
in the standard delivery.
13.5 Concealed installation, water connections
You will need the appropriate accessories to carry out the instal-
lation. See section 8.2, “Accessories”, pg. 12. The installation
kit for concealed water connections (not supplied, part number
200017 – IW-Kit LA) contains:
- 2 x plugs to seal the apertures in the water heater rear cover
- 2 x 45° twin connectors
- Filter screen with sealed edge for installation on the 45°twin
connector
- Flat gasket
Preparation
f Unscrew the twin connectors (including the filter screen) at-
tached to the water heater from the water supply pipes and
set them aside (not needed for this installation).
1 ¾″
44-46
D0000073660
f Seal the 45° twin connectors from the concealed water con-
nection installation kit. Screw the 45° twin connectors into
the wall connector.
To break out the apertures in the water heater back panel, you
will need to remove the function module from the back panel.

INSTALLATION
Service information
18 | DCE Premium www.stiebeleltronamericas.com
1.
4.
5.
2.
3.
D0000077971
f Undo the screw and disengage the locking tab.
f Push the function module on the back panel gently
backwards.
f Remove the function module from the water heater rear
cover by pulling it slightly forwards and lifting it out.
f Push/break out the required apertures in the back panel
from behind (for positions, see section 17.1, “Dimensions and
connections”, pg. 21). De-burr any sharp edges with a file.
f Install the function module in reverse order onto the water
heater back panel until it clicks into place.
f Secure the function module with the screw.
Mounting the water heater
D0000085464-b
21
1 Flat gasket
2 Filter screen with sealed edge
f Mark the 4drill holes, referencing their position on the water
heater rear cover.
f Drill the holes and secure the water heater using suitable
fixing materials (screws and wall anchors are not part of the
standard delivery): Countersunk screw, Ø4.5mm, max. di-
ameter of screw-head 9mm.
f Secure the DHW connection pipe with a flat gasket and the
cold water inlet line with the sealed-edge filter screen (from
the accessories) to the twin connectors.
f Seal the openings on the factory-installed water connections
using the plugs from the accessories.
14. Service information
Connection overview/component overview
D0000077189
1
2
3
4
5
6
7
1 Motorized valve
2 Flow meter
3 High limit safety cut-out, automatic reset
4 NTC sensor
5 Pin strips for connected load and anti-scalding protection
6 Programming unit plug-in position
7 Diagnostic lights

INSTALLATION
Troubleshooting
ENGLISH
www.stiebeleltronamericas.com DCE Premium| 19
15. Troubleshooting
WARNING Electrocution
Never remove or reinstall the water heater’s cover
unless the electricity servicing the unit is turned off.
Failure to do so could result in personal injury or death.
WARNING Electrocution
To test the water heater using the internal diagnostic
lights, it must be connected to the power supply.
When testing with the cover off, never touch any part
of the water heater. Doing so could result in serious
personal injury or death.
Note
When testing the water heater using the diagnostic lights,
water must be flowing through the unit.
Diagnostic lights
Red Lights up in the event of an error
Yellow Lights up in heating mode/flashes when output limit
reached
Green Flashing: Water heater connected to power supply
Diagnostic lights Problem Cause Solution
No LED is lit The water heater does not
heat up
There is no power Check to ensure the connected circuit breaker in the
main breaker panel hasn’t tripped. Reset if necessary
The PCB is faulty Replace the PCB
Green flashing, yellow
off, red off
No DHW The shower head/aerator is scaled up Descale or replace the shower head/aerators if nec-
essary
The filter screen in the cold water inlet is dirty Clean the filter screen
The flow meter is not plugged in Connect the cable to the PCB
The flow meter is faulty Replace the flow meter
The PCB is faulty Replace the PCB
Green flashing, yellow
on, red off
The display on the program-
ming unit is off
There is a loose cable between the PCB and the pro-
gramming unit
Check the cable and plug the cable into the program-
ming unit and/or PCB
The cable of the programming unit is faulty Check the cable and replace if necessary
The programming unit PCB is faulty Replace the programming unit, only available with a
new heater cover
The PCB is faulty Replace the PCB
Green flashing, yellow
on, red off
The outlet temperature does
not match the set value
The programming unit was not plugged in before
power was switched on
Perform a reset by switching off the power to the
water heater
The outlet sensor is faulty Replace the outlet sensor
The tap is faulty Replace the tap
The heating system is faulty Replace the PCB
The PCB is faulty Replace the PCB
Green flashing, yellow
flashing, red off
The outlet temperature does
not match the set value
Motorized valve limit reached Reduce the set temperature
Motorized valve is faulty Replace the motorized valve
Green flashing, yellow
off, red on
No DHW Air detected Continue draw-off for >1 minute
Diagnostic lights Display readout Problem Cause Solution
Green flashing, yellow
off, red on
Wrench flashes (displays
E1 and wrench in menu
“Fault code display”)
No DHW AE3 safety switch not activated during
commissioning
Activate AE3 safety switch by pressing the reset
button firmly. See section 11.3.1, “Initial AE3 safety
switch activation”, pg. 15
AE3 safety switch triggered by high limit
safety cut-out
Check high limit safety cut-out (plug-in connection,
connecting cable); activate AE3 safety switch
AE3 safety switch responds again after
high limit safety cut-out has been
checked; high limit safety cut-out faulty
Replace high limit safety cut-out; activate AE3 safety
switch and draw off water at the maximum set value
for >1 min
Safety switch responds again; PCB faulty Replace the PCB
Wrench flashes (displays
E2 and wrench in menu
“Fault code display”)
No DHW PCB faulty (lead break or short circuit in
inlet sensor)
Replace the PCB
Wrench flashes (displays
E3 and wrench in menu
“Fault code display”)
No DHW Short circuit in outlet sensor Check the outlet sensor, replace if necessary

INSTALLATION
Maintenance
20 | DCE Premium www.stiebeleltronamericas.com
16. Maintenance
WARNING Electrocution
Before performing any work on the appliance, discon-
nect all poles from the power supply.
16.1 Draining the water heater
The water heater can be drained for maintenance work.
WARNING Burns
Hot water may escape when you drain the appliance.
f Close the shut-off valve in the cold water inlet line.
f Open all draw-off valves.
f Undo the water connections on the water heater.
f Store the dismantled water heater free from the risk of frost,
as water residues remaining inside the water heater can
freeze and cause damage.
16.2 Cleaning the filter screen
WARNING Burns
Hot water may escape when you drain the appliance.
!
Material losses
To ensure that the Direct Coil™heating system is not dam-
aged following an interruption to the water supply, the
water heater must be restarted by taking the following
steps.
f Shut off power to the unit at the breaker panel by
making sure that connected circuit breakers are
“OFF” to avoid any danger of electric shock.
f Open and close the tap at least five times for three
minutes total, until the water heater and its up-
stream cold water inlet line are free of air.
f Switch the power back ON at the breaker panel.
The DCE has a built in sediment filter screen that should be cleaned
periodically:
16.2.1 Cleaning the filter screen, standard non-concealed
installation
f Turn off power to the water heater at the circuit breaker.
f Turn off the water supply to the water heater at the shut-off
valve.
f Open a connected hot water tap to relieve built-up pressure
(this will minimize leakage when removing the connection
from the cold water inlet).
f Disconnect the braided steel flex connector from the cold
water inlet fitting (right).
f To remove the filter screen from the bottom of the cold water
inlet, carefully insert a flathead screwdriver just above the
plastic lip of the filter screen, and gently pull downward.
f Clean the filter screen, re-insert securely into the cold water
inlet fitting, and reconnect the braid steel flex connector to
the cold water inlet.
f Open the cold water supply shut-off valve.
f Vent the air from pipes and the water heater by opening the
hot water faucet for a few minutes, until water flow is contin-
uous and all air is purged from the water pipes.
f Turn on circuit breaker to bring electrical power to the unit.
16.2.2 Cleaning the filter screen, concealed installation
f Cleaning the filter screen, concealed installation
f Turn off power to the water heater at the circuit breaker.
f Turn off the water supply to the water heater at the shut-off
valve.
f Open a connected hot water tap to relieve built-up pressure
(this will minimize leakage when removing the connection
from the cold water inlet).
f Open the water heater by loosening the screw and lifting the
cover up from the bottom.
f Unscrew the G3/8˝-union-nut from the cold water pipe
elbow.
f Clean the filter screen, located between inlet-line and twin
connector. (compare to picture in chapter concealed installa-
tion, water connections)
f Secure the cold water inlet line with the sealed-edge filter
screen.
f Open the cold water supply shut-off valve.
f Vent the air from pipes and the water heater by opening the
hot water faucet for a few minutes, until water flow is contin-
uous and all air is purged from the water pipes.
f Ensure there are no water leaks.
f Hook the cover into the water heater rear cover at the top
rear. Pivot the cover downwards. Check that the cover is se-
curely seated at both top and bottom. Secure the cover with
the screw.
f Turn on circuit breaker to bring electrical power to the unit.