STIEBEL ELTRON PER Operation Instruction

  • Prečítal som si návod na použitie pre Stiebel Eltron PER 18/21/24. Tento dokument podrobne popisuje inštaláciu a obsluhu tohto komfortného prietokového ohrievača vody, vrátane funkcií, ako je nastavenie teploty, funkcia ECO a bezdrôtové ovládanie. Som pripravený odpovedať na vaše otázky.
  • Ako môžem nastaviť teplotu?
    Čo je funkcia ECO?
    Ako môžem použiť pamäťové tlačidlá?
    Ako funguje detská poistka?
    Ako funguje bezdrôtové diaľkové ovládanie?
OPERATION AND INSTALLATION
OBSLUHA A INSTALACE
OBSŁUGA I INSTALACJA
ОБСЛУЖВАНЕ И ИНСТАЛИРАНЕ
ЭКСПЛУАТАЦИЯ И УСТАНОВКА
Fully electronically controlled comfort instantaneous water heater with Mini FFB wireless remote
control | Plně elektronicky regulovaný komfortní průtokový ohřívač s tlačítkem bezdrátového ovládání
Mini-FFB| Całkowicie elektronicznie regulowany komfortowy przepływowy ogrzewacz wody ze
zdalnym sterowaniem Mini-FFB | Изцяло електронно регулиран комфортен проточен бойлер
с безжичен превключвател Mini-FFB | Проточный нагреватель повышенной комфортности с
электронной системой полного регулирования и пультом дистанционного управления Mini-FFB
» PER 18/21/24
1
ECO
2
Made in Germany
2 | PER 18/21/24 www.stiebel-eltron.com
CONTENTS | SPECIAL INFORMATION
SPECIAL INFORMATION
- The appliance may be used by children aged3
and older and persons with reduced physical,
sensory or mental capabilities or a lack of expe-
rience and know-how, provided that they are su-
pervised or they have been instructed 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 applian-
ce or perform user maintenance unless they are
supervised.
- The tap can reach temperatures of up to 60°C.
There is a risk of scalding at outlet temperatures
in excess of 43°C.
- The appliance is suitable for supplying a shower
(shower operation). If the appliance is also or
exclusively used for shower operation, the qu-
alified contractor must limit the temperature
setting range using the temperature limit (55°C
or lower) in the appliance. When using preheated
water, it must be ensured that the inlet tempera-
ture does not exceed 55°C.
- Ensure the appliance can be separated from the
power supply by an isolator that disconnects all
poles with at least 3mm contact separation.
- The specified voltage must match the power
supply.
- The appliance must be connected to the earth
conductor.
- The appliance must be permanently connected to
fixed wiring.
- Secure the appliance as described in chapter "In-
stallation/ Installation".
- Observe the maximum permissible pressure (see
chapter "Installation/ Specification/ Data table").
- The specific water resistivity of the mains water
supply must not be undershot (see chapter "Insta-
llation/ Specification/ Data table").
- Drain the appliance as described in chapter "In-
stallation/ Maintenance/ Draining the appliance".
SPECIAL INFORMATION
OPERATION
1. General information �����������������������������������������3
1.1 Safety instructions ����������������������������������������������� 3
1.2 Other symbols in this documentation ����������������������� 3
1.3 Units of measurement ������������������������������������������ 3
2. Safety ���������������������������������������������������������� 3
2.1 Intended use ������������������������������������������������������ 3
2.2 General safety instructions ������������������������������������ 4
3. Appliance description ���������������������������������������4
4. Settings �������������������������������������������������������5
4.1 Settings and displays on the appliance ��������������������� 5
4.2 Settings in the INFO menu ������������������������������������� 6
4.3 Settings on the wireless remote control �������������������� 8
4.4 Further functions �������������������������������������������8
4.5 Recommended settings ���������������������������������������� 8
5. Cleaning, care and maintenance ���������������������������8
6. Troubleshooting ����������������������������������������������8
INSTALLATION
7. Safety ���������������������������������������������������������� 9
7.1 General safety instructions ������������������������������������ 9
7.2 Shower operation������������������������������������������������ 9
7.3 Instructions, standards and regulations �������������������� 9
8. Appliance description ������������������������������������� 10
8.1 Standard delivery ����������������������������������������������� 10
9. Preparation ������������������������������������������������� 10
9.1 Installation location �������������������������������������������� 10
9.2 Water installation ����������������������������������������������� 10
10. Installation �������������������������������������������������� 11
10.1 Standard installation ������������������������������������������� 11
10.2 Alternative installation methods�����������������������������13
10.3 Completing the installation �����������������������������������15
10.4 Installation of wireless remote control ��������������������� 15
11. Commissioning ��������������������������������������������� 15
11.1 Initial start-up ��������������������������������������������������� 15
11.2 Recommissioning �����������������������������������������������15
12. Appliance shutdown ��������������������������������������� 15
13. Troubleshooting �������������������������������������������� 16
13.1 Customer service mode ��������������������������������������� 16
14. Maintenance ������������������������������������������������ 17
15. Specification ������������������������������������������������ 17
15.1 Dimensions and connections ��������������������������������� 17
15.2 Wiring diagrams ������������������������������������������������ 18
15.3 Factory settings �������������������������������������������������18
15.4 DHW output ������������������������������������������������������ 18
15.5 Application areas/ Conversion table ����������������������� 18
15.6 Pressure drop ��������������������������������������������������� 18
15.7 Fault conditions �������������������������������������������������18
15.8 Test symbols ����������������������������������������������������� 19
15.9 Energy consumption data ������������������������������������� 19
15.10 Data tables ������������������������������������������������������� 19
GUARANTEE
ENVIRONMENT AND RECYCLING
OPERATION
General information
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OPERATION
1. General information
The chapters "Special information" and "Operation" are intended
for both users and qualified contractors.
The chapter "Installation" is 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.
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-se-
rious or minor injury.
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.
1.3 Units of measurement
Note
All measurements are given in mm unless stated otherwi-
se.
2. Safety
2.1 Intended use
The appliance is intended for domestic use. It can be used safely
by untrained persons. The appliance can also be used in non-
-domestic environments, e.g.in small businesses, as long as it is
used in the same way.
This pressurised appliance is suitable for heating domestic hot
water or for reheating preheated water. The appliance can supply
one or more draw-off points.
Any other use beyond that described shall be deemed inappropria-
te. Observation of these instructions and of the instructions for any
accessories used is also part of the correct use of this appliance.
!
!
OPERATION
Appliance description
4 | PER 18/21/24 www.stiebel-eltron.com
2.2 General safety instructions
Note
The remote temperature control has a lithium button cell
as a battery for the power supply.
Remove spent batteries. Leaking batteries cause dam-
age which is excluded from any warranty. Do not charge
non-rechargeable batteries.
Never use rechargeable batteries.
If the appliance is not used for a prolonged period, remo-
ve the battery (see chapter "Troubleshooting/ Replacing
the battery in the remote temperature control").
CAUTION Burns
The tap can reach temperatures of up to 60°C. There is a
risk of scalding at outlet temperatures in excess of 43°C.
CAUTION Burns
If operating with preheated water, e.g. from a solar ther-
mal system, the DHW temperature may vary from the
selected set temperature.
Where children or persons with limited physical, sensory or men-
tal abilities are allowed to use this appliance, we recommend a
permanent temperature limit. A qualified contractor can set the
limit for you.
!
Material losses
The user should protect the appliance and its tap against
frost.
3. Appliance description
The appliance heats water as it flows through it. The DHW outlet
temperature can be variably adjusted at the temperature selector.
From a certain flow rate, the control unit regulates the correct hea-
ting output, subject to the temperature selected and the current
cold water temperature.
The flow rate is automatically reduced by the flow regulator valve
when inlet temperatures are low and the required outlet tempera-
ture is high. This ensures that the required temperature is reliably
achieved. If operating the appliance with preheated water, "Error"
will appear on the display at temperatures of 45°C and above.
Two different temperatures can be saved and called up quickly.
The ECO function limits the flow rate to the ECO flow rate and sets
a pre-defined ECO temperature. The appliance also has child-
proofing functions, a Wellness program, automatic water volume
control, dynamic anti-scalding protection and a permanent tempe-
rature limiting feature. The background lighting on the appliance's
display can also be used as an orientation light.
Heating system
The bare wire heating system has a pressure-tested plastic ca-
sing. The heating system is suitable for hard and soft water areas
and is largely insusceptible to scale build-up. This heating system
ensures rapid and efficient DHW availability.
Note
The appliance is equipped with an air detector that lar-
gely prevents damage to the heating system. If, during
operation, air is drawn into the appliance, the appliance
shuts down for one minute, thereby protecting the hea-
ting system.
OPERATION
Settings
ENGLISH
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4. Settings
4.1 Settings and displays on the appliance
26�02�02�0929
Temperature display
Bar graph showing output
Second display
e.g. time
Memory buttons 1 and 2
Info and ECO button
ECO display
Temperature selector
Display field for additional information:
Service, error
Backlighting
Display field:
Wellness, automatic water volume control,
childproofing, ECO, second display, clock
Display field
Wellness Second line
Automatic water volume
control
Time
ECO mode Orientation light
Childproofing
Display field for additional information
Please contact your qualified contractor if the following sym-
bols are displayed:
Error
Service
4.1.1 Setting the temperature
The desired temperature can be variably adjusted by turning the
rotary selector. The set temperature is displayed.
Operation Display
Select a temperature
between 30 and 60°C via
stepless setting
e.g. 43°C
OFF = heating switched
off
4.1.2 Memory buttons
Using the memory buttons, you can quickly call up two preferred
temperatures. These temperatures can be selected by you.
Allocating memory buttons
Select the temperature
between 30 and 60°C that
you wish to save
e.g. 38°C.
Press button1 or button2 for
3seconds
e.g. 38°C and 43°C
Display flashes once brie-
fly, temperature is stored
Calling up memory buttons
Press button1 or button2 e.g. 38°C and 43°C
4.1.3 Selecting/deselecting ECO
The ECO function is activated and deactivated with the ECO button.
If you have activated the ECO function, a green LED below the
button lights up. The ECO symbol is also displayed.
The ECO function limits the flow rate to the ECO flow rate and sets
a pre-defined ECO temperature. Both values can be adjusted via
the INFO menu.
Note
The ECO function is deactivated each time you adjust the
temperature on the appliance (with the temperature se-
lector or via the memory buttons). You must then re-ac-
tivate the ECO function if required.
If you have selected the temperature via the wireless remote con-
trol, the ECO function is re-activated automatically after water has
been drawn off.
Press the ECO button:
Selecting ECO
Green LED illumi-
nates.
Press the ECO button:
Deselecting ECO
LED is not lit.
OPERATION
Settings
6 | PER 18/21/24 www.stiebel-eltron.com
4.2 Settings in the INFO menu
Use the ECO button to access the INFO menu, where you can set
comfort functions to individual preferences and/or call up values:
ECO temperature/flow rate adjustment, childproofing, Wellness
program, automatic water volume control. The ECO button can
also be used to set the brightness of the display and the orien-
tation light.
You can access the setting options by pressing the ECO button for
longer than three seconds.
Then press the ECO button again repeatedly to access each fun-
ction.
When you have reached the required function, you can change
the settings for that function by turning the temperature selector.
Operation Display
Accessing the menu
Press the ECO button for
3seconds
38°C
All settings in the INFO menu are saved immediately.
Exiting the menu
Press the ECO button for
3seconds.
Selected settings
If no button is pressed for approx.40seconds, the INFO menu is
exited.
4.2.1 ECO function
Setting the ECO temperature
Press the ECO button for
3seconds
38°C
Set the temperature,
range: 30-60°C
e.g. 40°C
Setting the ECO flow rate
Press the ECO button for
3seconds
38°C
Briefly press the ECO button 8.0l/min
Set the flow rate
4-15l/min
e.g.
6.0 l/min.
4.2.2 Setting the brightness of blue and red backlighting
The display on the appliance is equipped with background ligh-
ting. When you set a temperature up to 42.5°C, the background
lighting lights up blue; at temperatures of 43.0°C and above, the
display switches to red.
The display background lights up when you press a button, turn
the temperature selector or if water flows through the appliance
at a flow rate greater than the starting flow rate.
If no water is drawn off or the appliance is not operated for 30se-
conds, the background lighting switches off (only if a deactivated
orientation light has been selected).
If water is drawn off for more than 15minutes, brightness will be
reduced (reduction only with setting >20%).
The brightness of both the red and blue light can be individually
adjusted in 5 stages.
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
Blue
Red
Select the brightness for the
red and blue lighting
100%
20%
4.2.3 Activating/deactivating the orientation light
The backlighting helps you find your way in dark rooms. For this
purpose, you can set the lighting so it is constantly on. The orien-
tation light then lights up with the intensity of the set background
lighting.
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
OFF
Select "OFF"/"ON"
OFF:
ON:
deactivated
activated
4.2.4 Activating/deactivating/adjusting the childproofing
function
You can set the appliance to a maximum temperature.
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
OFF
Select "OFF"/"ON".
OFF:
ON:
deactivated
activated
Briefly press the ECO button 43 °C
Setting the temperature
e.g. 36°C
OPERATION
Settings
ENGLISH
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4.2.5 Activating/deactivating the Wellness comfort function
You can permanently program a Wellness comfort function which,
after water has been drawn for three minutes, reduces the tem-
perature by 10°C and then increases it again after 10 seconds.
After a further 10seconds, the temperature is lowered again by
10°C and then raised again after 10seconds. This temperature
change continues for the entire period that water is being drawn.
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
OFF
Select "OFF"/"ON"
OFF:
ON:
deactivated
activated
4.2.6 Activating/deactivating/adjusting the automatic water
volume control
You can set the automatic water volume control function so that
the flow rate is reduced to approx.4l/min once a specified volume
has been drawn off. This enables you to influence the amount of
water drawn as well as the duration of a shower. The selected
automatic water volume control only applies to the next draw-off.
Press the ECO button for
3seconds.
38°C
Press the ECO button briefly
several times.
OFF
Select "OFF"/"ON"
OFF:
ON:
deactivated
activated
When set to "ON", briefly
press the ECO button
80 l
Adjust the water volume
5-200 l
e.g. 150 l
4.2.7 Selecting the second line on the display
You can select what additional information is displayed in the
second line:
l/min Flow rate
kWh Energy consumption (you can set the values of these con-
sumption indicators to zero)
Water volume (you can set the values of these consumpti-
on indicators to zero)
Time Time (if the power supply has been interrupted you will
need to reset the clock)
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
Select the display value for
the second line
Selected display
Setting the "energy consumption and water volume" consumption
indicator to zero.
In the INFO menu, press
button1 and button2 simul-
taneously when the corre-
sponding consumption value
appears on the display
0
4.2.8 Setting the time
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
Set the time
e.g. 12:15
Note:
Reset the time after
a power interrup-
tion.
4.2.9 Wireless remote control – checking, pairing, unpairing
The appliance can be controlled remotely by means of
a wireless remote control. The transmitter is waterpro-
of and can also be used whilst showering or bathing.
Up to four wireless remote controls can be combined.
The wireless remote control enables you to control the tempera-
ture of the appliance remotely from another location (e.g. from
the kitchen sink).
The wireless remote control has four buttons for selecting the
temperature (38°C and 55°C are fixed settings; plus and minus
button for changing the temperature in 0.5°C stages). When a
signal is being sent to the appliance, the red LED on the wireless
remote control lights up.
If you press any button on the wireless remote control while the
appliance is in ECO mode, the ECO function is cancelled for the next
draw-off. ECO mode is resumed two minutes after the draw-off.
If the appliance is in standard mode, a constant temperature can
be selected via the wireless programming unit.
Wireless remote control check on the appliance
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
rc 1-4
Number of registered
wireless remote controls
(rc: remote control)
Pairing a wireless remote control with the appliance
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
rc 1
Press button1: Pairing phase
is activated.
Press any button on the wire-
less remote control.
Bar graph is shown.
Green LED flashes.
rc 2
Bar graph display goes
off.
Wireless remote control
is recognised
Unpairing a wireless remote control from the appliance
Press the ECO button for
3seconds
38°C
Press the ECO button briefly
several times
rc 2
In "rc" mode, press button2 rc 0: All wireless remote
controls are deregistered
OPERATION
Cleaning, care and maintenance
8 | PER 18/21/24 www.stiebel-eltron.com
4.2.10 Resetting to factory defaults
Press button1 and button2
simultaneously for 2seconds
Display flashes to con-
firm.
Anti-scalding protection and registered wireless remote controls
are not reset (for factory defaults, see chapter "Specification").
4.3 Settings on the wireless remote control
OFF
3s
D0000041708
Press 38°
Press 55°
Press +
Press -
38°C
55°C
Press 1x: Set value raised by 0.5°C.
Press 1x: Set value lowered by 0.5°C.
You can switch the appliance heater to OFF using the wireless
remote control. To do this, press the minus button for at least3se-
conds. Press any button to switch it back on.
4.4 Further functions
4.4.1 Dynamic anti-scalding protection
The appliance is equipped with dynamic anti-scalding protection.
The user who is first to select a temperature on the appliance or
via the wireless remote control sets the temperature for the next
draw-off. No other user can increase the temperature above 43°C
in the following two minutes or during a draw-off or for two mi-
nutes following the end of a draw-off.
4.4.2 Anti-scalding protection
The qualified contractor can permanently limit the temperature
(see chapter "Troubleshooting/ Customer service mode"). This
prevents water from flowing out of the appliance at temperatures
which could cause injury.
4.5 Recommended settings
Saving energy
The following recommended settings will result in the lowest
energy consumption:
- 38°C for hand washbasins, showers, bath
- 55°C for kitchen sinks
Thermostatic valve
If the appliance is being operated with a thermostatic valve, we
recommend setting the temperature on the appliance to maxi-
mum (temperature selector set to 60°C). You can then select the
required temperature at the thermostatic valve.
Following an interruption to the water supply
!
Material losses
Following an interruption of the water supply the appli-
ance must be recommissioned by carrying out the fo-
llowing steps, in order to prevent the destruction of the
bare wire heating system.
Disconnect the appliance from the power supply by
removing the fuses/tripping the MCBs.
Open the tap for one minute until the appliance and
its upstream cold water inlet line are free of air.
Switch the mains power back on again.
5. Cleaning, care and maintenance
Never use abrasive or corrosive cleaning agents. A damp
cloth is sufficient for cleaning the appliance.
Check the taps regularly. Limescale deposits at the tap out-
lets can be removed using commercially available descaling
agents.
6. Troubleshooting
Problem Cause Remedy
The appliance will not
start despite the DHW
valve being fully open.
There is no power.
Check the fuses/MCBs in
your fuse box/distributi-
on board.
The aerator in the tap or
the shower head is sca-
led up or dirty.
Clean and/or descale the
aerator or shower head.
Required temperature
>45°C is not achieved.
The water supply has
been interrupted.
Vent the appliance and
the cold water inlet line
(see chapter "Settings").
The cold water inlet tem-
perature is >45°C.
Reduce the cold water
inlet temperature.
The flow rate is too low.
ECO mode is activated
and the flow rate value in
ECO mode is set too low.
Set a higher ECO flow
rate.
It is not possible to set a
temperature higher than
43°C.
Dynamic anti-scalding
protection is enabled.
Is cancelled automati-
cally two minutes after
drawing has ceased.
If you cannot remedy the fault, notify your qualified contractor.
To facilitate and speed up your enquiry, please provide the serial
number from the type plate (000000-0000-00000):
Nr.: 000000-0000-00000
D0000041614
INSTALLATION
Safety
ENGLISH
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Wireless remote control battery change
Problem Cause Remedy
LED on the wireless
remote control flashes
during and after trans-
mission.
Battery in the wireless
remote control is flat.
Replace the battery.
!
Material losses
Remove the old battery.
Any damage caused by a leaking battery is excluded from
the warranty.
Open the housing of the wireless remote control by
unscrewing the two screws on the back and prising off the
casing.
Change the battery; for battery type, see chapter "Specificati-
on/ Data table".
Note
The positive terminal of the battery must face away from
the PCB.
Close the casing. When doing so, pay attention to the recess
on the edge of the lid. The recess determines the correct po-
sitioning of the lid and ensures the casing is tightly sealed.
Battery disposal
Never dispose of batteries with domestic waste. Spent
batteries may contain noxious substances that can be det-
rimental to the environment and human health. Dispose
of spent batteries through your dealer or via a central
recycling point for special waste.
INSTALLATION
7. Safety
Only a qualified contractor should carry out installation, commi-
ssioning, maintenance and repair of the appliance.
7.1 General safety instructions
We guarantee trouble-free function and operational reliability only
if original accessories and spare parts intended for the appliance
are used.
!
Material losses
Observe the maximum inlet temperature. Higher tem-
peratures may damage the appliance. You can limit the
maximum inlet temperature by installing a central ther-
mostatic valve.
WARNING Electrocution
This appliance contains capacitors which are discharged
when disconnected from the power supply. The capacitor
discharge voltage may briefly reach >60VDC.
7.2 Shower operation
CAUTION Burns
When supplying a shower, set the internal tempera-
ture limit to 55°C or lower; see chapter "Appliance
description / Customer service mode/ Anti-scalding
protection / Temperature limit menu".
CAUTION Burns
If the water supplied to the appliance is preheated, plea-
se note the following:
The internally adjustable temperature limit may be ex-
ceeded.
Limit the temperature with an upstream central
thermostatic valve.
7.3 Instructions, standards and regulations
Note
Observe all applicable national and regional regulations
and instructions.
- The IP 25 (hoseproof) rating can only be ensured with a co-
rrectly fitted cable grommet.
- The specific electrical resistivity of the water must not
fall below that stated on the type plate. In a linked water
network, observe the lowest electrical water resistivity
(see chapter "Specification/ Application areas/ Conversion
table"). Your water supply utility will advise you of the speci-
fic electrical water resistivity or conductivity.
INSTALLATION
Appliance description
10 | PER 18/21/24 www.stiebel-eltron.com
8. Appliance description
8.1 Standard delivery
The following are delivered with the appliance:
- Wall mounting bracket
- Threaded stud for wall mounting
- Installation template
- 2 twin connectors (cold water with shut-off valve)
- Flat gaskets
- Cable grommet (power cable from above/ below)
- Screws/ rawl plugs for securing the back panel to allow for
water connection on finished walls
- Mini FFB wireless remote control
For appliance replacement
- 2 tap extensions
Wireless remote control
OFF
3s
D0000041699
1 2 3
1 Transmitter incl. battery
2 Wall mounting bracket
3 Adhesive pad
9. Preparation
9.1 Installation location
!
Material losses
Install the appliance in a room free from the risk of frost.
Always install the appliance vertically and near the draw-off
point.
The appliance is suitable for undersink and oversink installation.
Undersink installation
26�02�02�1345
1
2
1 Cold water inlet
2 DHW outlet
Oversink installation
12
26�02�02�1344
1 Cold water inlet
2 DHW outlet
Note
Mount the appliance on the wall. The wall must have
sufficient load bearing capacity.
9.2 Water installation
- No safety valve is required.
- Safety valves are not permissible in the DHW pipe.
Flush the water line thoroughly.
Taps
Use appropriate pressure taps. Open vented taps are not permi-
ssible.
Note
Never use the shut-off valve in the cold water inlet to
reduce the flow rate. It is intended for shutting off the
appliance.
Permissible water line materials
- Cold water inlet pipe:
Pipes made from galvanised steel, stainless steel, copper or
plastic
- DHW outlet line:
Pipes made from stainless steel, copper or plastic
!
Material losses
If plastic pipework systems are used, take into account
the maximum inlet temperature and the maximum pre-
ssure (see chapter "Specification/ Data table").
Flexible water connection lines
If the appliance is installed with flexible water connection
lines, ensure that the pipe bends with bayonet fittings do not
become twisted inside the appliance.
Secure the back panel at the bottom with two additional
screws.
INSTALLATION
Installation
ENGLISH
www.stiebel-eltron.com PER 18/21/24 | 11
10. Installation
10.1 Standard installation
- Electrical connection from above; installation on unfinished
walls
- Water connection on unfinished walls
- Medium connected load is selected
For further installation options, see chapter "Alternative installa-
tion methods":
- Electrical connection from below on unfinished walls
- Electrical connection on finished walls
- Connecting a load shedding relay
- Water installation on finished walls
- Water connection on unfinished walls for appliance
replacement
- Operation with preheated water
- Installation of wireless remote control
Opening the appliance
D0000041615
Open the appliance by releasing the snap lock.
NT
T-
so
X1
26�02�02�0762
Remove the back panel by pressing the two locking hooks
and pulling the lower section of the back panel forwards.
Preparing the power cable
160
≥ 30
26�02�02�0887
Fitting the wall mounting bracket
26�02�02�0972
Mark out the holes for drilling using the installation templa-
te. If the appliance is to be installed with water connections
on finished walls, also mark out the fixing holes in the lower
part of the template.
Drill the holes and secure the wall mounting bracket with
2screws and 2rawl plugs (screws and rawl plugs are not
part of the standard delivery).
Fit the threaded stud provided.
Fit the wall mounting bracket.
Fitting the cable grommet
26�02�02�0950
Fit the cable grommet. For connecting cables >6mm², en-
large the hole in the cable grommet.
INSTALLATION
Installation
12 | PER 18/21/24 www.stiebel-eltron.com
Making the water connection
!
Material losses
Carry out all water connection and installation work in
accordance with regulations.
26�02�02�0948
Seal and insert the twin connectors.
!
Material losses
Never use the shut-off valve in the cold water inlet to
reduce the flow rate.
Preparing the back panel
!
Material losses
If you break open the wrong knock-out in the back panel
by mistake, you must use a new back panel.
18
kW
24
21
26�02�02�0884
Break out the cable grommet knock-out in the back panel.
Deburr any sharp edges with a file if necessary.
Installing the appliance
18
kW
24
21
26�02�02�0885
Push the back panel over the threaded stud and the cable
grommet. Pull the cable grommet by the locking hooks into
the back panel using pliers, until both locking hooks audibly
click into place.
Remove the protective transport plugs from the water
connections.
Press the back panel firmly into place and lock the fixing tog-
gle by turning it clockwise through 90°.
D0000041925
Screw the water connection pipes with flat gaskets onto the
twin connectors.
!
Material losses
The strainer must be fitted for the appliance to function.
When replacing an appliance, check whether the
strainer is installed (see chapter "Maintenance").
INSTALLATION
Installation
ENGLISH
www.stiebel-eltron.com PER 18/21/24 | 13
Making the electrical connection
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with relevant regulations.
WARNING Electrocution
The connection to the power supply must be in the form
of a permanent connection in conjunction with the remo-
vable cable grommet. Ensure the appliance can be sepa-
rated from the power supply by an isolator that disco-
nnects all poles with at least 3mm contact separation.
WARNING Electrocution
Ensure that the appliance is earthed.
!
Material losses
Observe the type plate. The specified voltage must match
the mains voltage.
Connect the power cable to the mains terminal (see chapter
"Specification/ Wiring diagrams").
Re-plugging the coding card
In its delivered condition, the appliance is set to 21kW. When
changing to a different connected load, carry out the following
steps:
18
kW
24
21
18
kW
24
21
D0000037821
Re-plug the coding card according to the selected connected
load (for selectable connected load and fuse protection of the
appliance, see "Specification/ Data table").
Tick the selected connected load on the type plate. Use a
ballpoint pen to do this.
Fitting the base part of the back panel
3
L
3’
4
L
2’
1
L
1’
2
L
L
L
NT C
T- sol
l
X11
26�02�02�1348
Position the lower back panel on the main back panel and
click it into place.
Align the mounted appliance by undoing the fixing toggle,
aligning the power supply and back panel, and then re-tigh-
tening the fixing toggle. If the back panel is not flush with the
wall, the appliance can be secured at the bottom with two
additional screws.
10.2 Alternative installation methods
10.2.1 Electrical connection from below on unfinished walls
18
kW
24
21
26�02�02�0890
Fit the cable grommet.
!
Material losses
If you break open the wrong knock-out in the back panel
by mistake, you must use a new back panel.
Break out the cable grommet knock-out in the back panel.
Deburr any sharp edges with a file if necessary.
Reposition the mains terminal in the appliance from the top
to the bottom.
Push the back panel over the threaded stud and the cable
grommet. Pull the cable grommet by the locking hooks into
the back panel using pliers, until both locking hooks audibly
click into place.
Press the back panel firmly into place and lock the fixing tog-
gle by turning it clockwise through 90°.
INSTALLATION
Installation
14 | PER 18/21/24 www.stiebel-eltron.com
10.2.2 Electrical connection on finished walls
Note
This type of connection changes the IP rating of the appli-
ance.
Change the type plate. Cross out "IP 25" and mark
the box "IP 24". Use a ballpoint pen to do this.
!
Material losses
If you break open the wrong knock-out in the back panel
by mistake, you must use a new back panel.
Cleanly cut or break out the required cable entries in the
back panel (for positions, see chapter "Specification/ Dimen-
sions and connections"). Deburr any sharp edges with a file if
necessary.
Route the power cable through the cable grommet and co-
nnect it to the mains terminal.
10.2.3 Connecting a load shedding relay
When operating additional electric appliances, such as electric
storage heaters, install a load shedding relay in the distribution
board. The relay responds when the instantaneous water heater
starts.
!
Material losses
Connect the phase that switches the load shedding relay
to the indicated terminal of the mains terminal in the
appliance (see chapter "Specification/ Wiring diagrams").
10.2.4 Water installation on finished walls
Note
This type of connection changes the IP rating of the appli-
ance.
Change the type plate. Cross out "IP 25" and mark
the box "IP 24". Use a ballpoint pen to do this.
26�02�02�0765
Fit water plugs with gaskets to seal the concealed
connections.
Fit a suitable pressure tap.
26�02�02�1006
Click the lower back panel section into place in the upper
section of the back panel.
Secure the connection pipes to the appliance.
Secure the back panel at the bottom with two additional
screws.
!
Material losses
If you break open the wrong knock-out in the back panel
by mistake, you must use a new back panel.
Cleanly break out the knock-outs in the appliance cover. De-
burr any sharp edges with a file if necessary.
Slide the lower back panel under the connection pipes of the
tap and click the lower back panel into place.
Secure the connection pipes to the appliance.
10.2.5 Water installation on unfinished walls for appliance
replacement
If the existing twin connectors of the old appliance only protrude
from the wall by approx.16mm, you cannot use the twin co-
nnectors provided.
Note
With this connection, the cold water supply can only be
shut off within the domestic installation.
16
D0000041634
Seal and fit the screw-in tap extensions provided.
Connect the appliance.
INSTALLATION
Commissioning
ENGLISH
www.stiebel-eltron.com PER 18/21/24 | 15
10.2.6 Operation with preheated water
You can limit the maximum inlet temperature by installing a cent-
ral thermostatic valve. For use in shower operation, the valve must
be set to a maximum of 55°C.
10.3 Completing the installation
Open the shut-off valve in the twin connector or the cold
water inlet line.
10.4 Installation of wireless remote control
You can attach the transmitter to the wall using the wall mounting
bracket.
Secure the wall mounting bracket to the wall using the adhe-
sive pad provided or a suitable countersunk screw (∅3mm
or less).
11. Commissioning
WARNING Electrocution
Commissioning must only be carried out by a qualified
contractor in accordance with safety regulations.
11.1 Initial start-up
D0000041617
Open and close all connected draw-off valves several times,
until all air has been purged from the pipework and the
appliance.
Carry out a tightness check.
Activate the safety pressure limiter by firmly pressing the
reset button (the appliance is delivered with the safety pres-
sure limiter deactivated).
Plug the temperature selector cable plug into the PCB.
Fit the appliance cover, ensuring it clicks into place. Check
that the appliance cover is seated correctly.
Switch the power supply ON.
Check the appliance function.
Mini FFB wireless remote control
The wireless remote control is registered with the appliance at the
factory. If there is no data communication during commissioning,
carry out the pairing process as follows:
Use the ECO button to switch to the comfort function "Wire-
less remote control (rc)"
Press memory button1 on the appliance (the pairing phase
is activated, bar graph is shown on display).
Then press a button on the wireless remote control.
Anti-scalding protection/ temperature limit
In customer service mode, you can limit the temperature to
between 31 and 60°C.
Appliance handover
Explain the appliance function to users and familiarise them
with how it works.
Make the user aware of potential dangers, especially the risk
of scalding.
Hand over these instructions.
11.2 Recommissioning
Vent the appliance and the cold water inlet line (see chapter
"Settings").
See chapter "Initial start-up".
12. Appliance shutdown
Isolate all poles of the appliance from the power supply.
Drain the appliance (see chapter "Maintenance").
INSTALLATION
Troubleshooting
16 | PER 18/21/24 www.stiebel-eltron.com
13. Troubleshooting
WARNING Electrocution
To test the appliance, it must be supplied with power.
Fault Cause Remedy
The flow rate is too
low.
Strainer and/or aera-
tor are dirty
Clean the strainer and/or aerator.
The motorised valve
is faulty.
Check the motorised valve. Repla-
ce it if required.
Permanent error
display on the pro-
gramming unit
The sensor/PCB is
faulty.
Further analyse the fault in custo-
mer service mode (see chapter
"Customer service mode").
Communication
between the pro-
gramming unit and
the control unit is
faulty.
Check the programming unit and
the connecting cable.
The background
lighting in the pro-
gramming unit is
completely off.
No mains power
Check the fuses/MCBs in your
fuse box/distribution board.
Loose connecting
cable to the pro-
gramming unit
Reconnect the cable.
Safety pressure limi-
ter has triggered.
Remove the cause.
Open a downstream draw-off
valve for 1minute. This depressu-
rises and cools down the heating
system, protecting it against
overheating.
Activate the safety pressure limi-
ter at flow pressure by pressing
the reset button.
Faulty PCB. Check the PCB and replace if
required.
Heating does not
switch on/ no hot
water.
Heater is faulty.
Check the heater and replace it if
required.
Flow meter faulty or
not plugged in.
Check the connection.
Check the flow meter in the
customer service mode.
The high limit safety
cut-out has respon-
ded or suffered a
lead break.
Remove the cause.
Activate the high limit safety cut-
-out, replace the high limit safety
cut-out if required.
Error display only
appears when water
is being drawn off.
One phase has
dropped out.
Check the fuses/MCBs in your
fuse box/distribution board.
Inlet temperature
>45°C.
See chapter "Water installation";
limit inlet temperature if nece-
ssary.
Intermittent cold
water.
Wellness function
enabled.
Disable the Wellness function.
Brief drop in flow
rate
The appliance restarts automati-
cally when an adequate flow rate
has been detected.
Air detector re-
sponds (cold water
for approx.1min).
The appliance restarts automati-
cally after a delay.
13.1 Customer service mode
Activate/deactivate customer service mode with the SERVICE bu-
tton on the back of the user interface (connection to "T-set" must
be present). Use the ECO button to move to the next menu item
(see chapter "Settings/ Settings in the INFO menu").
Scroll through the respective submenu by turning the temperature
selector.
1
26�02�02�0920
13.1.1 Fault menu
This menu is only shown if there is a fault.
Code Meaning
E1, ELEC The electronic assembly is faulty.
Replace the electronic assembly.
E 3, ntc Check the electrical connection to the outlet sensor. Replace it
if required.
E 4, mot Check the electrical connection to the motorised valve. Replace
it if required.
13.1.2 Control menu
Code Meaning
C 1, 36.5°C Display of the current inlet temperature. If the cold water sen-
sor is faulty, a temperature of 1.0°C is displayed.
C 2, 47.5 °C Display of the current outlet temperature. If the cold water
sensor is faulty, a temperature of 65.0°C is displayed.
C 3, 6.8 l/min Display of the current flow rate.
C 4, 21.5 kW Display of the current power consumption.
13.1.3 Data menu
Code Meaning
d 1, 8042 Service code for customer support
d 2, 2341 Number of days, on which the appliance is connected to the
power supply.
d 3, 172h Heating time in hours.
d 4, 24 kW Maximum output in kW: This output may deviate from the
rated output, e.g. if the mains voltage is not 400V.
INSTALLATION
Maintenance
ENGLISH
www.stiebel-eltron.com PER 18/21/24 | 17
13.1.4 Anti-scalding protection/ Temperature limit menu
Code Meaning
OFF Anti-scalding protection/ Temperature limit OFF.
On Anti-scalding protection/ Temperature limit ON.
31-60°C Maximum selectable value on appliance when ON
Factory defaults (see chapter "Specification").
After exiting customer service mode, you cannot change the set
maximum temperature via the user interface.
CAUTION Burns
If operating with preheated water, the set temperature
limit and anti-scalding protection may be ineffective.
In such cases, limit the temperature with an upstream
central thermostatic valve.
14. Maintenance
WARNING Electrocution
Before any work on the appliance, disconnect all poles
from the power supply.
Draining the appliance
The appliance can be drained for maintenance work.
WARNING Burns
Hot water may escape when draining the appliance.
Close the shut-off valve in the twin connector or the cold
water inlet line.
Open all draw-off valves.
Undo the water connections on the appliance.
Store the dismantled appliance in a room free from the risk
of frost, as water residues remaining inside the appliance can
freeze and cause damage.
Cleaning the strainer
26�02�02�0949
If dirty, clean the strainer in the threaded cold water fitting. Close
the shut-off valve in the cold water inlet line before removing,
cleaning and refitting the strainer.
15. Specification
15.1 Dimensions and connections
395
100
485
325
45
5
93
226
190
50
112
190
35
c01
c06
b02
D0000017757
b02 Entry electrical cables I
c01 Cold water inlet Male thread G 1/2 A
c06 DHW outlet Male thread G 1/2 A
Alternative connection options
325
50
50
35
40
b03
b02
b04
b04
b04
D0000019778
b02 Entry electrical cables I
b03 Entry electrical cables II
b04 Entry electrical cables III
INSTALLATION

18 | PER 18/21/24 www.stiebel-eltron.com
15.2 Wiring diagrams
3/PE ~ 380-415 V
85�02�02�0005
1 Heating
2 High limit safety cut-out
3 Safety pressure limiter
Priority control with LR 1-A
85�02�02�0003�
2
1
1 Control cable to the contactor of the 2nd appliance (e.g.
electric storage heater).
2 Control contact drops out when switching the instantaneous
water heater on.
15.3 Factory settings
Wellness OFF
Automatic water volume
control
OFF/ 80 l
ECO 38 °C / 8 l/min
Childproofing OFF/ 43.0°C
Second line of the display l/min
Orientation light OFF
Backlighting blue/ red 100 %
15.4 DHW output
The DHW output is subject to the mains voltage, the appliance's
connected load and the cold water inlet temperature. The rated
voltage and rated output can be found on the type plate (see
chapter "Troubleshooting").
Connected load in kW 38 °C DHW output in l/min.
Rated voltage Cold water inlet temperature
380 V      
16.2 7.0 8.3 10.1 12.9
19 8.2 9.7 11.8 15.1
21.7 9.4 11.1 13.5 17.2
18 7.8 9.2 11.2 14.3
21 9.1 10.7 13.0 16.7
24 10.4 12.2 14.9 19.0
19.4 8.4 9.9 12.0 15.4
22.6 9.8 11.5 14.0 17.9
25.8 11.2 13.2 16.0 20.5
Connected load in kW 
Rated voltage Cold water inlet temperature
380 V      
16.2 5.1 5.8 6.6 7.7
19 6.0 6.8 7.8 9.0
21.7 6.9 7.8 8.9 10.3
18 5.7 6.4 7.3 8.6
21 6.7 7.5 8.6 10.0
24 7.6 8.6 9.8 11.4
19.4 6.2 6.9 7.9 9.2
22.6 7.2 8.1 9.2 10.8
25.8 8.2 9.2 10.5 12.3
15.5 Application areas/ Conversion table
Specific electrical resistivity and specific electrical conductivity
(see chapter "Data table").
Standard specifica-


25 °C
Resisti-
vity ρ ≥
Conductivity σ Resisti-
vity ρ ≥
Conductivity σ Resisti-
vity ρ ≥
Conductivity σ
Ωcm mS/m μS/cm Ωcm mS/m μS/cm Ωcm mS/m μS/cm
900 111 1111 800 125 1250 735 136 1361
1000 100 1000 890 112 1124 815 123 1227
15.6 Pressure drop
Taps
Tap pressure drop at a flow rate of 10 l/min
Mono lever mixer tap, approx. MPa 0.04 - 0.08
Thermostatic valve, approx. MPa 0.03 - 0.05
Hand shower, approx. MPa 0.03 - 0.15
Sizing the pipework
When calculating the size of the pipework, an appliance pressure
drop of 0.1MPa is recommended.
15.7 Fault conditions
In the event of a fault, loads up to a maximum of 95°C at a pres-
sure of 1.2MPa can occur temporarily in the installation.
INSTALLATION

ENGLISH
www.stiebel-eltron.com PER 18/21/24 | 19
15.8 Test symbols
See type plate on the appliance.
15.9 Energy consumption data
Product datasheet: Conventional water heaters to regulation (EU)
no. 812/2013 and 814/2013
PER 18/21/24
233990
Manufacturer STIEBEL ELTRON
Load profile S
Energy efficiency class A
Energy conversion efficiency % 39
Annual power consumption kWh 479
Default temperature setting °C 60
Sound power level dB(A) 15
Special information on measuring efficiency Data at Pmax.
Daily power consumption kWh 2,186
15.10 Data tables
PER 18/21/24
233990
Electrical data
Rated voltage V 380 400 415
Rated output kW 16.2/19/21.7 18/21/24 19.4/22.6/25.8
Rated current A 27.6/29.5/33.3 29/31/35 30.1/32.2/36.3
Fuse protection A 32/32/35 32/32/35 32/32/40
Frequency Hz 50/60 50/60 50/-
Phases 3/PE
Max. mains impedance at 50Hz Ω 0.284 0.270 0.260
Specific conductivity σ
15
≤ (at ϑcold ≤25 °C) μS/cm 1111 1111 1000
Specific resistance ρ
15
≥ (at ϑcold ≤25°C) Ω cm 900 900 1000
Specific resistance ρ
15
≥ (at ϑcold ≤45°C) Ω cm 1200 1200 1300
Specific conductivity σ
15
≤ (at ϑcold ≤45°C) μS/cm 830 830 770
Connections
Water connection G 1/2 A
Application limits
Max. permissible pressure MPa 1
Max. inlet temperature for reheating °C 45
Values
Max. permissible inlet temperature °C 60
ON l/min >2.5
Pressure drop at flow rate MPa 0.08/0.1/0.13
Flow rate for pressure drop l/min 5.2/6.0/6.9
DHW delivery l/min 9.4/11.0/12.6
Δϑ on delivery K 26
Hydraulic data
Nominal capacity l 0.4
Versions
Adjustable connected load X
Temperature settings °C 30-60
Insulating block Plastic
Heating system heat generator Bare wire
Cover and back panel Plastic
Colour White
IP rating IP25
Dimensions
Height mm 485
Width mm 226
Depth mm 93
Weights
Weight kg 3.8
20 | PER 18/21/24 www.stiebel-eltron.com
INSTALLATION | GUARANTEE | ENVIRONMENT AND RECYCLING

GUARANTEE
ENVIRONMENT AND RECYCLING
Note
The appliance conforms to IEC 61000-3-12.
Mini FFB
Dimensions (H/W/D) excluding
wall mounting bracket
mm 50/50/17
Radio frequency MHz 868.3
Range inside a building incl.
one separating ceiling
m Approx. 25
Temperature setting range °C 30-60
IP rating to EN 60529 Shower
Bath
IP X5
IP X7
Battery type 1 x CR 2032
Guarantee
The guarantee conditions of our German companies do not
apply to appliances acquired outside of Germany. In countries
where our subsidiaries sell our products a guarantee can only
be issued by those subsidiaries. Such guarantee is only grant-
ed if the subsidiary has issued its own terms of guarantee. No
other guarantee will be granted.
We shall not provide any guarantee for appliances acquired in
countries where we have no subsidiary to sell our products.
This will not aect warranties issued by any importers.
Environment and recycling
We would ask you to help protect the environment. After use,
dispose of the various materials in accordance with national
regulations.
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