STIEBEL ELTRON WWK 222 Specification sheet

OPERATION AND INSTALLATION
Service control fascia
» Service-Bedienblende WWK 222/302/H

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CONTENTS | OPERATION
General information
OPERATION
1. General information
These instructions are intended for qualified contractors.
Note
Read these instructions carefully before using the appli-
ance and retain them for future reference.
Pass on the instructions to a new user if required.
Relevant documents
WWK222-302H operation and installation
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.
 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.
!
OPERATION
1. General information �����������������������������������������2
1.1 Safety instructions����������������������������������������������� 2
1.2 Other symbols in this documentation ����������������������� 3
2. Safety����������������������������������������������������������3
2.1 Intended use������������������������������������������������������ 3
3. Settings �������������������������������������������������������3
3.1 Display and controls��������������������������������������������� 3
3.2 Settings ������������������������������������������������������������ 4
 Menu ��������������������������������������������������������������� 4
 Indication of the amount of mixed water ������������������� 4
 Indication of the actual temperature ������������������������ 4
 Set temperature 1 ����������������������������������������������� 4
 Set temperature 2 ����������������������������������������������� 5
 Fan speed ��������������������������������������������������������� 5
 Indication of the air intake temperature �������������������� 5
 Runtime-dependent quick heat-up activation ������������� 6
 Runtime-dependent quick heat-up duration��������������� 6
 Changing units ��������������������������������������������������� 6
 Fault code ��������������������������������������������������������� 6
 E fault code ������������������������������������������������������� 7
 Advanced menu (with service plug only) ������������������� 7
 Integral sensor offset ������������������������������������������� 7
 Heating level������������������������������������������������������ 7
 Cylinder size ������������������������������������������������������ 7
 Override HP lock ������������������������������������������������� 7
 Override LP lock�������������������������������������������������� 8
 "Hot gas temperature exceeded" counter������������������� 8
 Hot gas temperature switching value������������������������ 8
 Fan lead time ����������������������������������������������������� 8
 Replacement sensor��������������������������������������������� 8
3.3 "Quick heat-up" key ��������������������������������������������� 8
4. Troubleshooting �������������������������������������������� 10
INSTALLATION
5. Safety�������������������������������������������������������� 12
5.1 General safety instructions ����������������������������������� 12
5.2 Instructions, standards and regulations ������������������� 12
6. Installation�������������������������������������������������� 12

OPERATION
Safety
ENGLISH
www.stiebel-eltron.com Service-Bedienblende WWK 222/302/H | 3
1.2 Other symbols in this documentation
Note
General information is identified by the adjacent symbol.
 Read these texts carefully.
Symbol Meaning
Material losses
(appliance damage, consequential losses and environmen-
tal pollution)
Appliance disposal
 This symbol indicates that you have to do something. The ac-
tion you need to take is described step by step.
2. Safety
2.1 Intended use
This product is a service control fascia for the maintenance and
repair of a domestic hot water heat pump, which does not have
its own display or controls.
Service control fascia Accessory for
321246 231209: WWK 222
233209: WWK 222 H
231211: WWK 302
232905: WWK 302 H
!
Material losses
The service control fascia must not be left on the appli-
ance once maintenance work is complete. Configuration
of parameters using the service control fascia may be
carried out only by a qualified contractor.
 Remove the service control fascia once maintenance
work is complete.
 Install the appliance cover.
3. Settings
3.1 Display and controls
Note
15seconds after every operation, the appliance auto-
matically reverts to the default display (amount of mixed
water) and saves the set value.
electronic comfort
2
5
4
D0000059162
3
1
1 Mixed water display (l|40°C)/
Indication of the actual temperature in the upper cylinder
section/
Indication of set temperature1/
Indication of set temperature2/
Fault code
2 "Plus" key
3 "Minus" key
4 "Quick heat-up" key
5 "Menu" key
3.1.1 Symbols
Symbol Description
Mixed water volume: The currently available amount of mixed water
at 40°C and at 15°C cold water temperature is shown.
Set temperature adjustment: Subject to intake temperature and
hot gas temperature, the appliance may temporarily reduce the set
temperature to the actual value captured by the integral sensor. The
appliance displays the "Set temperature adjustment" symbol and
blocks DHW heating until the actual temperature captured by the
integral sensor is 6K below the temporary set temperature. DHW
heating is then re-enabled and the originally selected set tempera-
ture is again applied.
Actual temperature: The current actual temperature is shown. The
actual temperature indicates the temperature in the upper section
of the DHW cylinder and therefore largely corresponds to the outlet
temperature.
Set temperature
External signal transmitter: Set temperature2 is the DHW tempera-
ture to which the appliance regulates if an external signal transmit-
ter is connected and active.
Standby: The symbol flashes, if the appliance PCB and load (com-
pressor) are separately supplied with voltage. This connection
option is required, if the appliance is to be operated via switchable
sockets in an energy management system (see "Electrical connecti-
on" chapter) for example.
electric emergency/booster heater: This symbol indicates the pre-
sence of a demand on this component. This symbol being displayed
does not necessarily mean that the electric emergency/booster hea-
ter is in operation.
!

OPERATION
Settings
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Heat pump: This symbol indicates the presence of a demand on this
component. This symbol being displayed does not necessarily mean
that the compressor is running.
Defrost active
Service/fault: Notify your qualified contractor if the "Service/fault"
symbol appears on the display. Continuous illumination of the sym-
bol indicates that the fault is not preventing appliance operation.
A flashing "Service/fault" symbol indicates that water is not being
heated and that it is essential you notify your qualified contractor.
Switching the appliance to emergency mode is a special case. The
electric emergency/booster heater will then heat the water despite
the flashing "Service/fault" symbol.
The symbols for electric emergency/booster heater and heat pump
are displayed when there is a demand for these appliances/compo-
nents. These symbols being displayed does not necessarily mean
that the electric emergency/booster heater and the heat pump
are active/running. Example: The appliance is in rapid/comfort
heat-up mode. The electric emergency/booster heater switches off
when the temperature in the upper cylinder section has reached
65°C. The heat pump has not yet heated the lower section to 65°C
and the rapid/comfort heat-up function has therefore not been
terminated yet. The electric emergency/booster heater symbol is
displayed until the rapid/comfort heat-up function has terminated.
3.2 Settings
In default display mode, the display shows the amount of mixed
water.
The "Menu" key allows you to call up all
information and adjustment options in
sequence. The relevant symbol appears.
 Menu
 Indication of the amount of mixed water
 Indication of the actual temperature
 Set temperature 1
 Set temperature 2
 Fan speed
 Indication of the air intake temperature
 Runtime-dependent quick heat-up ac-
tivation
In appliances with no electric
emergency/booster heater, this
parameter has no function.
 Runtime-dependent quick heat-up dura-
tion
In appliances with no electric
emergency/booster heater, this
parameter has no function.
 Changing units
 Fault code
 E fault code
 Advanced menu (with service plug only)
 Integral sensor offset
 Heating level
 Cylinder size
 Override HP lock
 Override LP lock
 "Hot gas temperature exceeded" counter
 Hot gas temperature switching value
 Fan lead time
 Replacement sensor
Menu
 Indication of the amount of mixed water
The currently available amount of mixed
water at 40°C and at 15°C cold water
temperature is shown.
"--L" is shown if less than 10l mixed
water is available.
DHW demand for Mixed water volume at 40°C
Bath 120-150 l
Shower 30-50 l
Washing hands 2-5 l
The amount of mixed water that can be achieved depends on the
cylinder capacity and the set temperature selected.
 Indication of the actual temperature
The "Actual temperature" symbol appe-
ars.
The current actual temperature is shown.
The actual temperature is the tempera-
ture in the upper section of the DHW
cylinder, and therefore largely corres-
ponds to the outlet temperature.
 Set temperature 1
Note
For hygiene reasons, never set the DHW temperature
below 60°C.
Set temperature1 is the DHW temperature to which the appliance
regulates if no external signal transmitter is connected and active.
Set temperature1 is factory set to 61°C.
Set temperature1 symbol appears.
Adjust set temperature1 from 20°C to
65°C using the "Plus" and "Minus" keys.
Note
Another way to adjust set temperature1 is to press the
"Plus" or "Minus" keys from within the default display
(mixed water volume).

OPERATION
Settings
ENGLISH
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Frost protection
Only frost protection remains active if you
set the set temperature to below 20°C
using the "Minus" key. The display shows
"--°C".
 Set temperature 2
Note
For hygiene reasons, never set the DHW temperature
below 60°C.
Set temperature2 is the DHW temperature to which the appliance
regulates if an external signal transmitter is connected and active.
The "External signal transmitter" symbol
appears.
Adjust set temperature2 from 20°C to
65°C using the "Plus" and "Minus" keys.
Operation with external signal transmitter
!
Material losses
See "Permissible voltage range for external signal trans-
mitters" in the "Specification/data table" chapter.
As standard, these appliances are designed in such a way as to
allow you to allocate a separate, individual set DHW temperature
to a connected external signal transmitter, such as a PV system or
an economy tariff transmitter. This set temperature 2 is activated if
the terminal connected to the external signal transmitter receives
a signal (see "Electrical connection/external signal transmitter
connection option" chapter). While activated, set temperature2
replaces the standard set DHW temperature (set temperature1).
If set temperature2 has been activated by the external signal
transmitter, this set temperature will then be active for at least
20minutes. If the external signal remains active after these 20mi-
nutes have passed, the compressor will run until the external sig-
nal drops out. If not, the selected set temperature1 is re-enabled.
When the relevant DHW set temperature has been reached, the
compressor switches off and remains off for a minimum idle time
of 20minutes.
The following diagram illustrates the connections by means of a
sample signal sequence from an external signal transmitter.
Example:
- Water temperature = 61°C
- Set temperature 1 = 60°C
- Set temperature 2 = 65°C
A
1
0
0510 15 20 25 30 35 40 45 50 55 60 65 70 75 t [min]
B
1
1
0 2
0510 15 20 25 30 35 40 45 50 55 60 65 70 75 t [min]
D0000034613
A External signal
B Compressor
1 20 min. minimum runtime, set temperature2
2 20 min. minimum compressor idle time
Note
An external signal must be present for at least 60seconds
before the control unit responds to it. This will prevent a
brief burst of sunshine from triggering a heat-up process,
for example which, in the absence of further sunlight, can
no longer be covered using locally generated PV power.
 Fan speed
The current set fan output appears, iden-
tified by a preceding F.
The qualified contractor can set the ma-
ximum speed percentage at which fans
should operate using the "Plus" and
"Minus" keys.
 Indication of the air intake temperature
An A appears as the air intake tempera-
ture symbol.
The current air intake temperature is
displayed.
The air intake temperature is displayed
only while the appliance fan is running. If
it is not possible to establish an air intake
temperature, two dashes are shown.

OPERATION
Settings
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 Runtime-dependent quick heat-up activation
Note
In appliances with no electric emergency/booster heater,
this parameter has no function.
Note
Only use runtime-dependent quick heat-up when requi-
red, and only with low intake temperatures, e.g. during
outdoor air operation in winter and in spring/autumn if
appropriate. Avoid using runtime-dependent quick he-
at-up at intake temperatures for which heating without
the electric emergency/booster heater normally covers
the prevailing demand. In such cases, selecting too short
a runtime leads to unnecessary electricity bills. The facto-
ry-preset runtime is 8hours and should not be less than
this with the function activated continuously.
To prevent excessive power consumption, disable the fun-
ction in summer and in spring/autumn if at all possible.
For improved comfort, the appliance offers a runtime-dependent
quick heat-up option. If the selected set temperature is not rea-
ched by the heat pump after a user-defined period, the appliance
switches on the electric emergency/booster heater in parallel to
back up the heat pump (subject to this function being enabled).
Once the set value has been reached, the electric emergency/
booster heater remains inactive until the set time has elapsed
again following a heat demand. As a factory default, this function
is disabled.
The period after which the electric emergency/booster heater
provides automatic back-up needs to be selected individually by
the user based on local conditions. DHW consumption and the
expected intake temperatures need to be considered.
This function is set in two stages. First enable the function and set
the runtime in the second parameter.
The tHE0 setting disables the runti-
me-dependent quick heat-up function.
This function is enabled via setting tHE1.
The function is disabled at the factory.
Switch between the tHE0 and tHE1 set-
tings using the "Plus" and "Minus" keys.
The tHE1 setting allows the electric emer-
gency/booster heater to cut in if the set
temperature is not reached after expiry
of the runtime selected below.
 Runtime-dependent quick heat-up duration
Note
In appliances with no electric emergency/booster heater,
this parameter has no function.
Set the runtime using the "Plus" and
"Minus" keys. After the set number of
hours, the appliance checks whether the
set temperature has been reached. If this
is not the case, the appliance switches on
the electric emergency/booster heater.
The factory default is 8hours.
thE1
tE08
thE0
t
D0000052266
1
2
1 Heat pump symbol
2 Electric emergency/booster heater symbol
tHE0 Runtime-dependent quick heat-up disabled
tHE1 Runtime-dependent quick heat-up enabled
tE08 Adjustable number of hours (e.g. 8 in this case) during
which heating is only provided by the heat pump
 Changing units
You can select whether the temperatures and the volume details
are displayed in SI units or US units. If you select 1, the values are
displayed in degrees Celsius and litres. If you select 0, the values
are displayed in degrees Fahrenheit and gallons.
Press the "Menu" key until "SI" appears
in the display.
Using the "Plus" and "Minus" keys, set
whether the display should use SI units
(1) or US units (0).
 Fault code
If the "Service/fault" symbol illuminates
or flashes, you can query the fault code
using the "Menu" key. This menu remains
disabled if no fault has arisen.
See the "Troubleshooting/ Fault codes" chapter.

OPERATION
Settings
ENGLISH
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 E fault code
A fault code preceded by E appears if the fault relates to the ref-
rigerant circuit. Notify a qualified contractor.
Advanced menu (with service plug only)
Note
The menu items listed below are accessible only if a
service plug is inserted into slot X1 at the back of the
programming unit.
In the delivered condition, a service plug is inserted into
slot X1.
D0000060217
1
1 Slot X1
 Integral sensor offset
You can manually calibrate the integral sensor with the value set.
This should be done only following after the DHW cylinder has
been fully heated up without any DHW being drawn-off.
Example: The configured, active set temperature is 55 °C. The
integral sensor of the appliance checks when the set temperature
is reached. If the compressor switches off after heat-up, query the
actual temperature (detected by the sensor at the cylinder top)
using the programming unit. If the actual temperature is 60 °C,
for example, set the integral sensor offset to 5K.
Temperature at the sensor at the cylinder top = integral sensor
temperature + offset
Press the "Menu" key until "lo" appears
in the display.
You can change this value using the "Plus"
and "Minus" keys in the range between
-5 and 5.
 Heating level
The set charging level influences the compressor start hysteresis
and start temperature applied to the integral sensor value, to
which it is regulated. The higher the configured charging level,
the lower the start hysteresis.
The start temperature cannot be read.
The compressor starts DHW heating when the available amount
of mixed water decreases to the percentage of maximum water
volume set in this parameter. The charging level function is only
effective from a minimum set temperature of 41 °C, as the amount
of mixed water is only calculated if the sensor at the cylinder top
captures a temperature above 40 °C.
A further start condition, which overlaps the heat-up level start
conditions, is the reduction of the temperature captured by the
sensor at the cylinder top to 6 K below the active set temperature.
Press the "Menu" key, until an "L" follo-
wed by a number appears in the display.
You can change this value using the "Plus"
and "Minus" keys in the range between
30 and 100.
 Cylinder size
The cylinder size is required for accurate calculation of the mixed
water volume. You can switch the cylinder size between 200 l and
300 l using the "Plus" and "Minus" keys.
If the PCB is replaced, you will need to set the cylinder size.
If you see the value 9999 as cylinder size parameter, you must set
one of the suitable appliance cylinder sizes.
 Override HP lock
The appliance will be locked out if the HP sensor responds 5 times
within 5 hours.
To override the HP lockout, press the
"Quick heat-up" key.

OPERATION
Settings
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 Override LP lock
The appliance will be locked out if the LP sensor responds 5 times
within 5 hours. This menu item allows you to override the lockout.
Note
Currently appliances are built without LP sensors.
 If this lockout arises, check the jumper on the PCB (X0/L –
X1/6 – A1/X2/ND).
To override the LP lockout, press the
"Quick heat-up" key.
 "Hot gas temperature exceeded" counter
The counter indicates how often the hot gas temperature has
exceeded the set hot gas temperature switching value during
heat-up.
To reset the counter to 0, press the "Quick
heat-up" key.
 Hot gas temperature switching value
!
Material losses
Factory default setting: 105°C
Only a service technician is permitted to change his pa-
rameter in line with factory instructions.
When this set hot gas temperature switching value is exceeded,
the "hot gas temperature exceeded" counter increments and the
set temperature temporarily reduces to the temperature captured
by the integral sensor.
Press the "Menu" key until "h" appears
in the display.
You can change this value using the
"Plus" and "Minus" keys. Value range:
100°C to 120°C
Example: Set temperature is 65°C. At an actual temperature of
61 °C, for example due to a critical intake temperature, the ap-
pliance detects an impermissible high hot gas temperature. The
appliance temporarily reduces the set temperature to 61 °C. The
appliance stops. Below the heat-up level (this refers to the cur-
rently applicable set value, thus 61 °C and not 65 °C), and when the
hot gas temperature has dropped again, the compressor restarts
and operates with the originally configured set temperature (65
°C). The set temperature is reduced again if the appliance cannot
reach this set temperature because the hot gas temperature has
been excessively high.
 Fan lead time
!
Material losses
Factory default setting: 30s
Only a service technician is permitted to change his pa-
rameter in line with factory instructions.
The set value specifies the number of seconds the fan runs, before
the compressor is enabled.
Press the "Menu" key until "u" appears
in the display.
You can change this value using the
"Plus" and "Minus" keys.
 Replacement sensor
If the integral sensor is faulty, switch this parameter to replace-
ment sensor operation using the "Plus" key.
When replacement sensor operation is active, fault 4 is perma-
nently hidden and set temperature 1 is displayed in the default
display in place of the amount of mixed water.
IE0 Standard mode
IE1 Replacement sensor operation
3.3 "Quick heat-up" key
Note
In appliances with no electric emergency/booster hea-
ter, this key allows you to override the HP/NP lockout.
You cannot start quick/comfort heat-up or emergency
heating mode.
Press the "Quick heat-up" key.
The heat pump and electric emergency/
booster heater symbols appear.

OPERATION
Settings
ENGLISH
www.stiebel-eltron.com Service-Bedienblende WWK 222/302/H | 9
3.3.1 Quick/comfort heat-up
Normally, the "Quick heat-up" key is used to activate the quick/
comfort heat-up function, which enables you to cover an unexpec-
tedly high DHW demand without changing any of the appliance's
standard settings.
If quick/comfort heat-up is activated manually by pressing the
relevant key, the heat pump and the electric emergency/boos-
ter heater will start in parallel, irrespective of the selected set
temperature, and will remain active until the DHW temperature
in the cylinder has reached 65°C. To save energy, the electric
emergency/booster heater switches off early, as soon as a tem-
perature of 65°C has been achieved in the upper cylinder section
(quick heat-up).
The quick/comfort heat-up function remains active until a tem-
perature of 65°C has been achieved in the entire DHW cylinder
(comfort heating). The appliance then automatically switches back
to the previously set parameters.
Note
The electric emergency/booster heater and heat pump
symbols are displayed until the quick/comfort heat-up
function has terminated.
During quick/comfort heat-up, the electric emergency/
booster heater symbol is displayed until the heat pump
has heated the entire cylinder to 65°C and the function
is terminated. The electric emergency/booster heater al-
ready switches off when the 65°C has been achieved in
the upper cylinder section.
Note
If the quick/comfort heat-up has been activated unin-
tentionally, you can cancel the function by lowering the
set temperature.
 Hold down the "Minus" key, until you hear a clicking
noise caused by the heat pump and emergency/
booster heater switching off. At the same time, the
set temperature also reverts to the value that was
selected before quick/comfort heat-up was enabled.
3.3.2 Emergency mode
If the appliance is faulty, you can use the emergency mode to
activate the electric emergency/booster heater.
Following a DHW demand, the appliance measures the tempe-
rature rise every 15 minutes. Where the temperature rise was
<0.25°C within the 15 minutes interval, this is recorded by a
counter. The compressor shuts down if the temperature rise did
not reach >0.25 °C in any 15 minute interval over 13 hours. The
fault key flashes on the display and a fault code indicates that the
appliance is not heating the water.
In this case you can activate emergency mode by pressing the
"Quick heat-up" key. After the "Quick heat-up" key has been pres-
sed, the indicated fault code increments by a value of 256, as
the fault codes are added together (see fault code table in the
"Troubleshooting" chapter). The fault key continues to flash. The
electric emergency/booster heater is activated.
The current set temperature (set temperature1 or set tempera-
ture2) is ignored. In emergency mode, the appliance operates
with a fixed set temperature of 40°C. Following one-time enabling
of this function by means of the "Quick heat-up" key, this function
remains enabled for 7days.
Following 7days of emergency operation the electric emergency/
booster heater is disabled. The fault code shown on the display
decrements by256.
If you press the "Quick heat-up" key again within the 7days of
emergency operation, the 7-day runtime for emergency mode
will restart again.
If the 7-day runtime for emergency mode has passed, you can
restart emergency operation for a further 7days by pressing the
"Quick heat-up" key.
Pressing the "Quick heat-up" key only enables emergency mode if
an error with fault code8 occurred previously. In standard mode
pressing the "Quick heat-up" key only triggers one-time heat-up
of the DHW cylinder.
Emergency mode is disabled by an interruption of the power sup-
ply. The appliance tries again to heat with the heat pump. Fault
code8 is only set after 13hours. Only then can emergency mode
be manually re-enabled via the "Quick heat-up" key.

OPERATION
Troubleshooting
10 | Service-Bedienblende WWK 222/302/H www.stiebel-eltron.com
4. Troubleshooting
Problem Cause Remedy
No hot water is
available.
No power at the appli-
ance.
Check that the appliance
is connected to the power
supply.
A fuse/MCB in the fuse
box has blown/tripped.
Check whether the fuses/
MCBs in your fuse box have
blown/tripped. If required,
disconnect the appliance from
the power supply and replace
the fuses/reset the MCBs.
Contact your qualified cont-
ractor if the fuse/MCB blows/
trips again after the appliance
is re-connected to the power
supply.
The air intake or air
discharge of the appliance
is blocked.
Check the air intake grille and
air discharge grille for dirt
accumulations. Remove any
dirt (see the "Maintenance and
care" chapter).
The ambient tempera-
ture exceeds the upper
application limit (see
the "Specification/ Data
table" chapter). The ap-
pliance safety equipment
has responded and the
appliance has shut down
automatically.
Wait for the appliance to cool
down. Call a qualified contrac-
tor if the appliance does not
restart automatically.
The ambient tempe-
rature falls below the
lower application limit
(see the "Specification/
Data table" chapter). The
evaporator is being de-
frosted intermittently.
Wait until the appliance
restarts automatically.
The appliance is
not heating the
DHW cylinder
although the heat
pump symbol is
illuminated.
The compressor lockout
time has not yet elapsed.
Once the compressor has
been switched off, it will
only be switched back on
again after the 20minute
compressor lockout time
has elapsed.
The safety valve of
the cold water inlet
line is dripping.
These units are under
water mains pressure.
During the heat-up pro-
cess, expansion water will
drip from the safety valve.
Notify a qualified contractor if
water continues to drip when
heat-up has been completed.
The condensate
drain drips.
The surface temperature
of the evaporator is lower
than the dew point tem-
perature of the ambient
air. Condensate forms.
The amount of condensate
depends on the humidity level
of the ambient air.
The room tempera-
ture drops too low.
Operation of the appliance can
cause the room temperature
to fall by 1 to 3°C. If the room
temperature falls by more
than 5°C, check the room size
(see the "Specification/Data
table" chapter). Increasing the
room size by opening a door
to another room will remedy
this.
Service/fault sym-
bol is permanently
on.
See the "Fault codes"
chapter.
See the "Fault codes" chapter.
Problem Cause Remedy
Service/fault sym-
bol flashes and
the water does not
heat up.
See the "Fault codes"
chapter.
See the "Fault codes" chapter.
Defrost symbol is
shown.
The appliance is in defrost
mode.
No action required.
The heat pump
symbol is flashing.
There is a heat demand,
but the compressor is
locked out.
No action required. The com-
pressor restarts automatically
after the compressor lockout
time has elapsed. The com-
pressor lockout time lasts
20minutes once the compres-
sor has been shut down. The
symbol stops flashing auto-
matically.
The electric emer-
gency/booster
heater symbol is
flashing.
A temperature controller
has switched off the elec-
tric emergency/booster
heater during quick he-
at-up.
No action required. The ap-
pliance continues the quick
heat-up process using the
heat pump. The symbol stops
flashing when the controller
re-enables the electric emer-
gency/booster heater. The
symbol extinguishes when the
temperature throughout the
DHW cylinder reaches the set
temperature of 65°C.
Fault code
You can call up a fault code if the Service/fault symbol is flashing
or continuously lit on the display.
Repeatedly press the "Menu" key until
the fault code is shown after set tempe-
rature2.
Fault code appears
Fault
code
Service/
fault
symbol
Fault description Remedy
2 conti-
nuously
illumina-
ted
The sensor at the cylinder top is
faulty. The actual temperature
display changes over to the
integral sensor. The appliance
continues to deliver heat. The
amount of mixed water shown
is always less than 10 litres.
4 conti-
nuously
illumina-
ted
The integral sensor is faulty.
In the event of a faulty integral
sensor, the integral sensor is
set to the value of the sensor at
the cylinder top, and amount of
mixed water is calculated using
this value. The appliance conti-
nues to deliver heat.
We recommend installing
a replacement sensor. The
replacement sensor must
be activated in the appli-
ance menu.