STIEBEL ELTRON DEL 18 SL electronic LCD Instruction Manual

OPERATION AND INSTALLATION
Electronically controlled instantaneous water heater
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M1 Tmax M2

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CONTENTS | SPECIAL INFORMATION
SPECIAL INFORMATION
OPERATION
1. General information 23
1.1 Safety instructions 23
1.2 Other symbols in this documentation 23
1.3 Units of measurement 23
2. Safety 23
2.1 Intended use 23
2.2 General safety instructions 23
2.3 CE designation 24
2.4 Test symbols 24
3. Appliance description 24
4. Settings and displays 25
4.1 User interface 25
4.2 Temperature limit (child-proofing) 25
4.3 Inlet temperature information 26
4.4 Following an interruption to the water supply 26
5. Cleaning, care and maintenance 26
6. Troubleshooting 26
INSTALLATION
7. Safety 27
7.1 General safety instructions 27
7.2 Instructions, standards and regulations 27
8. Appliance description 27
8.1 Standard delivery 27
8.2 Accessories 27
9. Preparations 28
9.1 Installation site 28
10. Installation 29
10.1 Standard installation 29
10.2 Completing the installation 31
10.3 Installation options 31
11. Commissioning 34
11.1 Initial start-up 34
11.2 Recommissioning 35
12. Shutting down the system 35
13. Troubleshooting 35
13.1 Service mode 35
13.2 Indicator options for LED diagnostic traffic light 36
13.3 Fault table 36
14. Maintenance 36
15. Specification 37
15.1 Dimensions and connections 37
15.2 Wiring diagram 37
15.3 DHW output 38
15.4 38
15.5 Pressure drop 38
15.6 Fault conditions 38
15.7 Details on energy consumption 38
15.8 Data table 39
WARRANTY
ENVIRONMENT AND RECYCLING
SPECIAL INFORMATION
-
-
-
-
-
-
The appliance may be used by children aged
8 and up and persons with reduced physical,
sensory 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 appliance safely and have
understood the resulting risks. Children must
never play with the appliance. Children must
never clean the appliance or perform user
maintenance unless they are supervised.
Risk of scalding: The tap can reach tempera-
tures in excess of 50°C
Ensure the appliance can be separated from
the power supply by an isolator that discon-
nects all poles with at least 3mm contact sep-
aration.
Secure the appliance as described in chapter
"Installation / Installation”.
Observe the maximum permissible pressure
(see chapter “Specification / Dat table”).
Drain the appliance as described in chapter
"Installation / Maintenance / Draining the
appliance”.

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ENGLISH
OPERATION
General information
OPERATION
1. General information
The chapter "Operation" is intended for appliance users
and qualified contractors.
The chapter "Installation" is intended for qualified
contractors.
Note
Read these instructions carefully before using the
appliance 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 here.
1.1.2 Symbols, type of risk
Symbol Type of risk
!Injury
Electrocution
Burns or 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-serious or minor injury.
1.2 Other symbols in this documentation
Note
Notes are bordered by horizontal lines above and below
the text.General information is identified by the symbol
shown on the left.
Read these texts carefully.
Symbol
!Material losses
(appliance damage, consequential losses and
environmental pollution)
Appliance disposal
This symbol indicates that you have to do something.
The action you need to take is described step by step.
1.3 Units of measurement
Note
Unless specified otherwise, all dimensions are
given in mm.
2. Safety
2.1 Intended use
This appliance is intended for domestic use. It can be
used safely by untrained persons. The appliance can
also be used in a non-domestic environment, e.g. in a
small business, as long as it is used in the same way.
This pressure-tested 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
inappropriate. Observation of these instructions and of
instructions for any accessories used is also part of the
correct use of this appliance.
2.2 General safety instructions
CAUTION Burns
During operation, the tap can reach temperatures in
excess of 50°C, e.g. in the case of water that has
been preheated by solar energy.
There is a risk of scalding at outlet temperatures in
excess of 43 °C.
!
WARNING Injury
The appliance may be used by children aged 8 and
up and persons with reduced physical, sensory or
mental capabilities or a lack of experience and
know-how, provided that they are supervised or they
havebeen instructed on how to use the appliance
safely and have understood the resulting risks.
Children must never play with the appliance.
Children must never clean the appliance or perform
user maintenance unless they are supervised.

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OPERATION
Where children or persons with limited physical, sensory
or men tal abilities are allowed to use this appliance, we
recommend a permanent temperature limit. The limit can
be set by you or a contractor:
- The temperature limit (child-proofing) is user adjustable
- Anti-scalding protection can be enabled by a qualified
contractor.
!
Damage to the appliance and environment
Protect the appliance and its tap against frost.
2.3 CE designation
The CE designation shows that the appliance meets all
essential requirements according to the:
- Low Voltage Directive
- Electromagnetic Compatibility Directive
The maximum permissible mains impedance is
indicated in chapter "Specification".
2.4 Test symbols
See type plate on the appliance
Country-specific approvals and certifications: Germany
In line with [German] State Building Regulations, a
general test certificate has been issued for the appliance,
as verification of its suitability regarding noise emissions.
DIN 4109
PA-IX 6816/I
3. Appliance description
The electronically controlled instantaneous water heater
with automatic output matching maintains a consistent outlet
temperature. This is irrespective of the inlet temperature, up
to the maximum output of the appliance.
DHW temperature
The DHW outlet temperature can be variably adjusted.
The selected temperature is displayed.
Display backlighting
Temperature limit (child-proofing)/ anti-scalding protection
The display has white backlighting. During the draw-off
process or a temperature adjustment, backlighting is enabled.
The temperature limit (child-proofing) can be individually
set using the Tmax key. The selected temperature then
limits the setting range of the DHW outlet temperature.
The qualified contractor can also enable static anti-scalding
protection from 43 for you (see chapter “Alternative
installation options/ Anti-scalding protection”). The anti-
scalding temperature then functions as the upper limit for
the DHW outlet temperature and for the temperature limit
(child-proofing).
Heating system
The heating system is suitable for hard and soft water
areas; it has low susceptibility to scale build-up. This system
ensures rapid and efficient DHW availability.
Note
The appliance is equipped with an air detector,
which largely prevents damage to the heating system.
If, during operation, air is drawn into the appliance,
heating out put is shut down automatically for one
minute, thereby protecting the heating system.
-
Appliance description

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OPERATION
4. Settings and displays
4.1 User interface
M1 Tmax M2
D0000040726
2
3
1
5
4
1 Temperature selector
2 LED scalding risk indicator
3 Memory keys M1 and M2
4 Display
Temperature limit T max5
Display symbols
1
2
3
4
D0000040989
1 In the event of an appliance fault, a spanner appears
The temperature limit can be individually set between 30°C
and 60°C
2 Segment display for temperature setting with °C
Performance bar, 10-100%3
4 Tmax, displayed when temperature limit is enabled
Setting the temperature
M1 Tmax M2
D0000040726
2
1
3
1
2 Call up preferred temperatures
Set temperature setting range 30 - 60°C (without end-stop)
35°C to 43°C in 0.5°C increments, other temperature
ranges in 1°C incerments
3 Set the temperature limit
Memory keys M1 and M2 can each be assigned a preferred
temperature.
Select a preferred temperature.
Press one of the M keys for 3 seconds to save the
preferred temperature . The temperature is confirmed
with 1x flashing.
!
Note
If the outlet temperature is not sufficiently high when
the draw-off valve is fully open and the temperature
selector is set to maximum, then more water is
flowing through the appliance than can be heated
by the heating system (working at maximum output).
Reduce the water volume at the draw-off valve
until the required temperature delivery is achieved.
4.2 Temperature limit (child-proofing)
M1 Tmax M2
D0000040981
Enabling the temperature limit (child-proofing)
Press and hold the Tmax key for > 6 seconds.The
set value display flashes and the current temperature
limit is shown.
The value for the temperature limit can be changed while
the display is flashing. If no key is pressed for 10 seconds,
the display stops flashing and the value is stored. The
display then shows the set value and the Tmax symbol.
Disabling the temperature limit (child-proofing)
The Tmax symbol on the display is no longer shown.
Press and hold the Tmax key > 6 seconds.
Inlet temperature information
If the inlet temperature is higher than the preferred temperature,
e.g. if water has been preheated by solar energy, the display
alternates between showing "hot" and the measured inlet
temperature. The LED scalding risk indicator also flashes.
Settings and displays

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ENGLISH
OPERATION
4.3 Inlet temperature information
If the inlet temperature is higher than the preferred
temperature, e.g. if water has been preheated by solar
energy, the display alternates between showing "hot"
and the measured inlet temperature. The LED scalding
risk indicator also flashes.
Recommended setting for operation with a thermostatic
valve and water preheated by solar energy
Set the temperature at the appliance to the max.
temperature.
4.4
Following an interruption to the water supply
!
Material losses
Following an interruption of the water supply the
appliance must be recommissioned by carrying out
the following 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/valves regularly. Limescale deposits
at the spouts can be removed using commercially
available descaling agents.
6. Troubleshooting
Fault Cause Remedy
The appliance will
not start despite the
DHW valve being
fully open.
There is no voltage in the
appliance.
Check the fuses/MCBs in
your fuse box.
The aerator in the tap or
the shower head is scaled
up or contaminated.
Clean and/or descale the
aerator or shower head.
The water supply has been
interrupted.
Vent the appliance and the
cold water inlet line (see
chapter "Settings / Following
an interruption to the water
supply").
Cold water flows
briefly while hot
water is being
drawn.
The air sensor detects air
in the water and the ap -
pliance's heating output is
briefly switched off.
The appliance restarts
automatically after 1 minute.
The temperature at
the appliance cannot
be set to > 43 °C
The child-proofing Tmax is
enabled.
Disable the child-proofing
(see chapter "Appliance
description")
The anti-scalding protec -
tion in the appliance is
enabled.
Your qualified contractor
can disable the anti-scald -
ing protection for you.
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 (000000-0000-000000):
No.:000000-0000-000000
DEL ... SL
26_02_02_1125_
Cleaning, care and maintenance

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OPERATION
INSTALLATION
7. Safety
Only a qualified contractor should carry out installation,
commissioning, 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.
Flow pressure
If the flow rate is not sufficient to switch on the appliance
even when the tap is open, remove the flow limiter and
replace it with the plastic profile washer supplied.
If required, the pressure in the water installation can
also be raised.
Note
To ensure the thermostatic valve works properly,
you should not replace the flow limiter in this valve
not replace the flow limiter in this valve with the
plastic profile washer.
!
Material losses
Observe the maximum inlet temperature. Higher
temperatures may damage the appliance. You can
limit the maximum inlet temperature by installing a
central thermostatic valve (see chapter” Appliance
description Accessories”).
7.2 Instructions, standards and regulations
Note Observe all applicable national and local instructions and
regulations, e.g. DIN 1988 / DIN EN 806 in Germany.
- The protection rating IP 25 (hoseproof) can only be
ensured with a correctly fitted cable grommet.
- The specific electrical resistance of the water must not
fall below that stated on the type plate. In a linked water
net work, factor in the lowest electrical resistance of
the water (see chapter “ Specification / Application
areas”). Your water supply utility will advise you of the
specific electrical water resistance or conductivity.
8. Appliance description
8.1 Standard delivery
The following are delivered with the appliance:
- Wall mounting bracket
- Installation template
- 2 twin connectors
- Cross-piece
- Tee
- Flat gaskets
- Strainer
- Plastic profile washer
- 2 flow limiters
- Plastic connection pieces / installation aid
- Cover and back panel guides
8.2 Accessories
Taps/valves
Plug G1/2 A
- MEKD - kitchen pressure tap
- MEBD - bath pressure tap
The plugs are required if you use any taps other than the
pressure taps for finished walls recommended in the
accessories.
Installation set for finished walls
-
- Compression fitting - copper pipe
Solder fitting - copper pipe for solder connection Ø12mm
- Compression fitting - plastic pipe (suitable for Viega: San-
fix-Plus or Sanfix-Fosta)
Universal mounting frame
Mounting frame with electrical connections.
Pipe assembly for undersink appliances
This assembly is required for undersink installation where
you need to have the water connections (G3/8A) above the
appliance.
Pipe assembly for offset installation
This pipe assembly with pipe bends is required if you
need to have the appliance vertically offset against the water
connection by approx. 90mm downwards.
Pipe assembly for replacing a gas water heater
This pipe assembly is required if the existing installation has
gas water heater connections (cold water connection on the
left and DHW connection on the right).
Pipe assembly for DHB water plug-in couplings
2 water plug-in couplings for connecting the appliance to the
existing water plug-in connections of a DHB.
Safety

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OPERATION
-
Load shedding relay (LR 1-A)
The load shedding relay for installation in the distribution
board provides priority control for the instantaneous water
heater when other appliances, such as electric storage
heaters, are simultane ously being operated.
ZTA 3/4 - central thermostatic valve
The thermostatic valve is for central premixing, for
example on an instantaneous water heater with solar
thermal system.
Service monitor
Diagnostic unit for detecting faults in the appliance.
9. Preparations
Flush the water line thoroughly.
Taps/valves
Use suitable taps (see chapter “ Appliance description/
Accessories"). Open vented taps are not permissible.
A safety valve is not required.
Note
Never use the cross-piece to reduce the flow rate. The
cross-piece should only be used to shut off the appliance.
Permissible water pipe materials
- Cold water inlet pipe:
galvanised steel pipe, stainless steel pipe, copper pipe or
plastic pipe
- DHW outlet pipe:
stainless steel pipe, copper pipe or plastic pipe
!
Material losses
If plastic pipework systems are used, take into account
the maximum inlet temperature and the maximum
permissible pressure (see chapter “ Specification / Data
table”)
Flow rate
Ensure that the flow rate (see chapter “ Specification /
Data table", On) is sufficient for switching on the
appliance.
Increase the mains water pressure if the required flow
rate is not sufficient with an open draw-off valve.
Flexible water connection lines
If the appliance is installed with flexible water
connection lines, ensure that the pipe bends do not
become twisted. Pipe bends have a bayonet fitting
and are installed inside the appliance.
Secure the back panel with an additional screw at the
bottom.
Appliance with adjustable connected load
The appliance DEL 18/21/24 SL electronic LCD is factory
set to 21kW. For other outputs, proceed as follows:
Plug in the coding card according to the selected output;
for selectable output and fuse protection of the appliance,
see "Specification".
Tick the selected output on the type plate. Please use
a ball point pen to do this.
9.1 Installation site
!
Material losses
Only install the appliance in rooms 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 installations.
Note
Mount the appliance on a sufficiently load-bearing wall.
Undersink installation
1
2
D0000040728
1 Cold water inlet
2 DHW outlet
Oversink installation
1
2
D0000040736
1 Cold water inlet
2 DHW outlet
Preparations

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OPERATION
Operation
10.Installation
10.1Standard installation
- Electrical connection in the lower section of the
appliance for installation on unfinished walls
- Water connection for installation on unfinished walls
- For the appliance with adjustable connected load,
the middle load is preset.
For further installation options, see chapter "Installation
options".
electr o nic comf ort
D0000040738
Open the appliance.
26_02_02_1101
Remove the back panel by pressing the two locking hooks
and pulling the lower part of the back panel forwards.
26_02_02_0810_
Use the installation template to mark out the holes for drill -
ing. If the appliance is to be installed with water connections
for finished walls, also mark out the fixing hole in the lower
part of the template.
Drill the holes and secure the wall mounting bracket with
part of the standard delivery).
Note
If you are installing the appliance with flexible water
connections, also secure the back panel with a screw.
Fit the wall mounting bracket.
160
30
1
26_02_02_0824_
1 Installation aid
Prepare the power cable.
Making the water connection
!
Material losses
Carry out all water connection and installation work in
accordance with regulations.
26_02_02_0798
Seal and insert the twin connectors.
26_02_02_0799
2
3
1
3
1 Cold water with 3-way ball shut-off valve
2 DHW with tee
3 Gasket
Fit the water connections.
26_02_02_0856
Fit the strainer provided in the 3-way ball shut-off valve
!
Damage to the appliance and environment
The strainer must be fitted for the appliance to function.
When replacing the appliance, check that the strainer
is present.

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26_02_02_1334
21
1 Plastic profile washer
2 Flow limiter
Note
-
- With an increased cold water inlet temperature, e.g.
in the case of water preheated by solar energy.
-When using the appliance for showering.
With low water pressure.The pressure drop can be
reduced by replacing the flow limiter with the plastic
profile washer provided.
Installing the appliance
26_02_02_1336
For easy installation, push the cable grommet of the
upper electrical connection into the back panel from
behind.
Remove the transport plugs from the water connections.
Remove the fixing toggle from the upper part of the
back panel.
Route the power cable through the cable grommet from
behind, until the power cable rests against the cable
sheath. Align the power cable.
If the cross-section is > 6 mm2, enlarge the hole in the
cable grommet.
Press the appliance over the threaded stud of the wall
mounting bracket. When doing so, push through the
soft seal in the back panel of the appliance. If necessary,
use a screwdriver.
Push the fixing toggle on to the threaded stud of the wall
mounting bracket.
Push the back panel of the appliance on to the wall.Turn the
fixing toggle 90° clockwise to lock the appliance in place.
26_02_02_0921
Fit the pipes with flat gaskets onto the twin connectors.
Connecting the power supply
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with relevant regulations.
WARNING Electrocution
Connection to the power supply is only permissible
in the form of a permanent connection in conjunction
with the removable cable grommet. Ensure the
appliance can be separated from the power supply
by an isolator that disconnects all poles with at least
3mm contact separation.
WARNING Electrocution
Ensure that the appliance is earthed.
!
Damage to the appliance and environment
Observe the type plate. The specified voltage must
match the mains voltage.
26_02_02_1122_
Connect the power cable to the mains terminal (see chapter
“Specification / Wiring diagram”). The specified voltage must
match the mains voltage.
INSTALLATION
Installation
Install the blue flow limiter (7.5 l/min) as standard.
Use the brown flow limiter (12 l/min) in the
following instances:

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INSTALLATION
Installation
Adjustable connected load
With the DEL 18/21/24 SL, 3 connected load stages can be
selected. The middle load is preset. With a different connected
load, proceed as follows:
D0000047341
Select the connected load you require (see chapter
"Specification / Data table”).
Plug in the coding card according to the selected connected
load.
Change the type plate.Tick the selected connected load.
Please use a ballpoint pen to do this.
10.2Completing the installation
Open the 3-way ball shut-off valve.
26_02_02_1102_
Fit the lower part of the back panel. Ensure that it clicks into
place.
Align the mounted appliance by loosening the fixing toggle,
aligning the electrical connection and back panel, and then
re-tightening the fixing toggle. If the back panel of the appli-
ance is not flush, the appliance can be secured at the bottom
with an additional screw.
10.3Installation options
- Electrical connection from above on unfinished walls
- Electrical connection on finished walls
- Large cross-section for electrical connection from below
- Connecting a load shedding relay
- Water installation on finished walls
- Water installation for finished walls with solder / compres
sion fitting
- Water installation on finished walls, fitting the appliance
cover
- Installation of lower back panel with threaded fitting on fin
ished walls
- Use of existing wall mounting bracket when replacing an
appliance
- Installation with offset tiles
- Pivoting appliance cover
- Operation with preheated water
Anti-scalding protection / temperature limit
-
Electrical connection from above on unfinished walls
Cut open the cable grommet for the power cable.
Push down the locking hook to secure the mains terminal.
Pull out the mains terminal.
Reposition the mains terminal in the appliance from the
bottom to the top and secure the mains terminal by sliding it
under the locking hook.
Route the control wires below the wire guide.

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INSTALLATION
Installation
Power cable for finished walls
Cut or break out the required entries in the back panel and
appliance cover cleanly (for positions, see chapter
"Specification / Dimensions and connections”). If necessary,
use a file.
Route the power cable through the cable grommet. Connect
the power cable to the mains terminal.
Note
This type of connection changes the protection
rating of the appliance.
Change the type plate. Cross out "IP 25" and mark
the box "IP 24". Please use a ballpoint pen to do this.
Large cross-section for electrical connection from below
If you use cables with a large cross-section, you can fit the
cable grommet after the appliance has been installed.
1.
3. 4.
2.
26_02_02_1124_
Before installing the appliance, use a screwdriver to push out
the cable grommet.
Slide the cable grommet over the power cable.For this, use
the installation aid. If the cross-section is > 6 mm2, enlarge
the hole in the cable grommet.
Push the cable grommet into the back panel.
Connecting a load shedding relay
Install the load shedding relay in the distribution board in conjunc-
tion with other electric appliances, e.g. electric storage heaters.
The relay responds when the instantaneous water heater starts.
The load shedding relay is available as an accessory.
!
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 diagram”).
Water installation on finished walls
Suitable pressure-tested taps can be ordered as accessories.
D0000033104
1
2
1 Water plug
2 Pressure tap for finished walls
Fit the water plugs with gaskets to seal the in-wall connec-
tion. All pressure taps listed in the accessories are supplied
with plugs and gaskets as part of the standard delivery.
Install the tap.
Place the lower section of the back panel under the tap con-
nection pipes. Slide the lower section of the back panel into
place.
Fit the connection pipes to the appliance.
Water installation for finished walls with solder /
compression fitting
With the solder fitting or compression fitting accessories you can
connect both copper and plastic pipes.For installation, prepare
the appliance cover, see chapter "Water installation on finished
walls, fitting the appliance cover".
The solder fitting with threaded fitting is suitable for 12 mm copper
pipes.
Push the union nuts over the connection pipes.
Solder the inserts to the copper pipes.
Slide the lower section of the back panel under the tap con-
nection pipes. Push the lower section of the back panel into
place.
Fit the sealing elements on to the connection pipes.
Fit the connection pipes to the appliance.
Note
Observe the tap manufacturer's instructions.

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INSTALLATION
Installation
Water installation on finished walls,
fitting the appliance cover
26_02_02_0821
4
3
1
4
3
3
3
1 Back panel guides
2 Screw
3 Cover guides
4 Pipe aperture
Cleanly break out the knock-out apertures in the appliance
cover. If necessary, use a file.
Note
If the tap connection pipes are slightly offset, the appli-
ance can be sealed using the tabs on the cover guides.
If the tap connection pipes are offset, do not fit any
back panel guides.
If installing tap connection pipes which are not offset, break
off the tabs on the cover guides.
Click the cover guides into place in the pipe apertures.
Position the back panel guides on the pipes.
Push them to-
gether. Then push the guides until they are resting against
the back panel.
Secure the back panel at the bottom with a screw.
Installation of lower back panel with threaded fitting on
finished walls
You can install the lower back panel after fitting the taps.
1
2
26_02_02_1080
1 Connection pieces delivered in the pack
2 Screw
Cut open the lower back panel at the markings.
Fit the lower back panel by bending it out at the sides and
guiding it over the pipes.
Insert the connection pieces into the lower back panel from
behind.
Click the lower back panel into place.
Secure the lower back panel with a screw.
Wall mounting bracket when replacing an appliance
When replacing an appliance, you can use an existing wall mounting
bracket of a Stiebel Eltron appliance.
(except for a DHF instantaneouswater heater).
Press the appliance over the threaded stud of the existing
wall mounting bracket. When doing so, push through the soft
seal in the back panel of the appliance.If necessary, use a
screwdriver.
DHF replacement
26_02_02_0815_
Reposition the threaded stud on the wall mounting bracket
(the stud has a self-tapping thread).
Rotate the wall mounting bracket 180° and mount it on the
wall (the DHF logo is then turned towards the reader).
Installation with offset tiles
110
20
26_02_02_1066_
2
1
1 Minimum contact area of the appliance
2 Maximum tile offset
Adjust the wall clearance. Lock the back panel with the fixing
toggle by turning it 90° clockwise.

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INSTALLATION
Commissioning
Pivoting appliance cover
You can rotate the appliance cover for undersink installation.
electronic comfor t
electr oniccomfort
D0000040745
Remove the programming unit from the appliance cover by
pressing the locking hooks and taking out the programming
unit.
Turn the appliance cover (not the appliance) and refit the
programming unit, ensuring that all locking hooks click into
place. When clicking the locking hooks into place, make sure
you press against the inner side of the appliance cover (shad-
ed area).
Plug the set value transducer cable into the PCB (see chapter
“Commissioning / Initial start-up”).
Hook the appliance cover in at the bottom.Pivot it up to the
back panel.
Ensure the all-round seal of the back panel is firmly seated
by pushing the cover gently forwards and back.
Secure the appliance cover.
Operation with preheated water
Anti-scalding protection / temperature limit
By installing a central thermostatic valve you will limit the max -
Accessories").
60
43
D0000040985
2
1
1 Position 43:Maximum temperature setting 43°C
2 Position 60:No temperature limit, for temperature setting
range, see chapter “Specification / Data table”.
Remove the appliance cover.
Slide the switch to the required position.
Fit the appliance cover.
11.Commissioning
WARNING Electrocution
Commissioning may only be carried out by an authorised
contractor in accordance with the safety regulations.
11.1Initial start-up
electroniccomfort
D0000040746
Open and close all connected draw-off valves several times,
until all air has been vented from the pipework and the
appliance.
Check for leaks in the appliance screw joints.
Activate the safety pressure limiter for flow pressure by
firmly pressing in the reset button (the appliance is delivered
with the safety pressure limiter disabled).
Push the temperature selector plug into the "set tempera-
ture" PCB.
Fit the appliance cover and secure with a screw.
Switch the mains power ON.
Check the function of the appliance.
Remove the protective foil from the user interface.

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INSTALLATION
Shutting down the system
Appliance handover
Explain the appliance function to users and familiarise them
with its operation.
Make users aware of potential dangers, especially the risk of
scalding.
Hand over these instructions.
11.2Recommissioning
See chapter "Settings and displays / Following aninterruption to
the water supply"
12.Shutting down the system
Isolate all poles of the appliance from the power supply.
Drain the appliance (see chapter "Maintenance").
13.Troubleshooting
WARNING Electrocution
In order to check the appliance it must be
connected to the power supply.
13.1Service mode
M1 Tmax M2
D0000040982
M1
12
1 Memory keys M1 and M2
2 Spanner symbol
The spanner symbol is displayed in the event of a fault or when
the appliance is in service mode.
Activate customer service mode by pressing and holding down
both memory keys M1 and M2 for > 6 seconds.
Disable customer service mode by briefly pressing one of the
three keys. Service mode is automatically terminated after
30 seconds of inactivity.
Fault displays
--- No display, there is no fault
ntc Outlet sensor malfunction
ELE Faulty PCB

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INSTALLATION
Maintenance
13.2Indicator options for LED diagnostic traffic light
Indicator options
Red Illuminates in the event of a fault
Yellow Illuminates during heating mode
Green Flashing:Appliance is supplied with mains power
13.3Fault table
LED diagnostic
traffic light
Fault Cause Remedy
No display No hot water. The fuse/MCB in the fuse box has blown/responded. Check the fuses/MCBs in your fuse box.
The safety pressure limiter has responded. Remove the cause of the fault
(e.g. faulty pressure washer).
Protect the heating system against overheating
by opening a draw-off valve downstream of the
appliance for one minute.This depressurises
and cools down the heating system.
Activate the safety pressure limiter at flow
pressure by pressing the reset button; see also
chapter "Initial start-up".
The PCB is faulty. Check the PCB, replace if required.
Flashing green
light
The appliance does not start. Inadequate flow rate. Descale / clean the connected aerator /
shower head.
Inadequate flow rate. Clean the strainer in the water inlet.
No hot water at flow rate
> 3 l/min.
The flow sensor (DFE) plug has not been inserted. Plug the flow sensor plug back in.
The flow sensor (DFE) is faulty. Check the flow sensor and replace if required.
Flashing green
light and steady
yellow light
No hot water at flow rate of
> 3 l/min.
The high limit safety cut-out has responded or its
lead is broken.
Check the appliance and the high limit safety
cut-out.
The set temperature is not
achieved.
One phase down. Check the fuses/MCBs in your fuse box.
The heater is faulty. Measure the resistance of the heating system
and replace if required.
The outlet temperature sensor is faulty. Check the outlet temperature sensor and
replace if required.
The appliance is at its output limit. Reduce the flow rate or install the flow limiter.
The outlet temperature is approx.
45°C , irrespective of the set
value transducer
The set value transducer or connecting cable is faulty,
or the connecting cable is not attached.
Attach the connecting cable; replace the set
value transducer if required.
A set temperature of > 43°C
is no achieved.
The temperature limit (child-proofing) /
anti-scalding protection is enabled.
Disable the temperature limit (child-proofing)/
anti-scalding protection.
Flashing green
light and steady
red light
No hot water.
The outlet temperature sensor is faulty. Check the outlet temperature sensor and
replace if required.
The cold water sensor is faulty.
The flow rate is > 25 l/min
Check the PCB, replace if required.
The air sensor detects the presence of air in the water
and briefly interrupts the heating output.
The appliance restarts after one minute.
Reduce the flow rate or install the flow limiter.
Selected temperatures about
45°Care not achieved.
The cold water inlet temperature is above 45°C
(e.g.in the case of water preheated by solar energy).
Reduce the cold water inlet temperature to the
appliance.
14.Maintenance
WARNING Electrocution
Before any work on the appliance, disconnect all poles
from the power supply.
Draining the appliance
You can drain the appliance for maintenance work or to protect
it from frost.
CAUTION Scalding
Hot water may escape when draining the appliance.
Close the shut-off valve in 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.

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INSTALLATION
Maintenance
15.Specification
15.1Dimensions and connections
478
100
414
44
105≤ 20225
140
30
35
35
114
368
b02
c01c06
D0000017971
Alternative connection options
165
50
44
30
35
72
325
338
47
b03
b02
b04
b04
b04
b04 b04
D0000019212
DEL SL
b02
b03
b04
c01 Cold water inlet Male thread G 1/2 A
c06 DHW outlet Male thread G 1/2 A
15.2Wiring diagram
3/PE ~ 380-415 V
85_02_02_0005_
1 Heater
2 High limit safety cut-out
3 Safety pressure limiter
Priority control with load shedding relay (LR 1-A)
See also chapter “Appliance description / Accessories”.
85_02_02_0003_
2
1
1 Control cable to contactor of second appliance (e.g. electric
storage heater).
2 Control contact, opens when instantaneous water heater is
switched on.
Entry electrical cables I
Entry electrical cables II
Entry electrical cables III

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INSTALLATION
Specification
15.3DHW output
The DHW output is subject to the mains voltage, the connected
load of the appliance 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 400 V 415 V 5 °C 10 °C 15 °C 20 °C
16,2 7,0 8,3 10,1 12,9
16,3 7,1 8,3 10,1 12,9
18,0 7,8 9,2 11,2 14,3
19,0 8,2 9,7 11,8 15,1
19,4 8,4 9,9 12,0 15,4
21,0 9,1 10,7 13,0 16,7
21,7 9,4 11,1 13,5 17,2
22,6 9,8 11,5 14,0 17,9
23,5 10,2 12,0 14,6 18,7
24,0 10,4 12,2 14,9 19,0
24,4 10,6 12,4 15,2 19,4
25,8 11,2 13,2 16,0 20,5
26,0 11,3 13,3 16,1 20,6
27,0 11,7 13,8 16,8 21,4
Connected load in kW 50 °C DHW output in l/min.
Rated voltage Cold water inlet temperature
380 V 400 V 415 V 5 °C 10 °C 15 °C 20 °C
16,2 5,1 5,8 6,6 7,7
16,3 5,2 5,8 6,7 7,8
18,0 5,7 6,4 7,3 8,6
19,0 6,0 6,8 7,8 9,0
19,4 6,2 6,9 7,9 9,2
21,0 6,7 7,5 8,6 10,0
21,7 6,9 7,8 8,9 10,3
22,6 7,2 8,1 9,2 10,8
23,5 7,5 8,4 9,6 11,2
24,0 7,6 8,6 9,8 11,4
24,4 7,7 8,7 10,0 11,6
25,8 8,2 9,2 10,5 12,3
26,0 8,3 9,3 10,6 12,4
27,0 8,6 9,6 11,0 12,9
15.4
Specific electrical resistance and specific electrical conductivity
(see chapter "Data table").
Standard specification
at 15 °C 20 °C 25 °C
Resist -
ance ρ
Conductivity σResist -
ance ρ
Conductivity σResist -
ance 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
15.5Pressure drop
Taps/valves
Pressure drop at taps, at 10 l/min flow rate
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
To calculate pipework sizing, apply a pressure drop of
0.1 Mpa to the appliance.
In the event of a fault, loads up to a maximum of 80°C, at a
pressure of 1.0 MPa, can temporarily occur in the installation.
15.6Fault conditions
15.7Details on energy consumption
Product data complies with EU regulations relating to the Directive
on the ecodesign of energy related products (ErP).
DEL 18/21/24 SL DEL 27 SL
233678 233679
Manufacturer STIEBEL ELTRON STIEBEL ELTRON
Load profile S S
Energy efficiency category A A
Annual power consumption kWh 477 473
Energy efficiency % 39 39
Default temperature setting °C 60 60
Sound power level dB(A) 15 15
Special information on measuring the efficiency Data at Pmax. None
Application areas / conversion table

39 | DEL SL electronic LCD www.stiebel-eltron.com
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INSTALLATION
Specification
15.8Data table
DEL 18/21/24 SL DEL 27 SL
233678 233679
Electrical details
Rated voltage V 380 400 415 380 400 415
Rated output kW 16.2/19/21.7 18/21/24 19.4/22.6/25.8 24.4 27
Rated current A 27.6/29.5/33.3 29/31/35 30.1/32.2/36.3 37.1 39
Fuse A 32/32/35 32/32/35 32/32/40 40 40
Phases 3/PE 3/PE
Frequency Hz 50/60 50/60 50/- 50/- 50/- 50/-
Specific resistance ρ
15
≥(atϑcold ≤25 °C) Ωcm 900 900 1000 900 900 1000
Specific conductivityσ15 ≤(atϑµS/cm 1111 1111 1000 1111 1111 1000
Specific resistance ρ
15
≥(atϑcold ≤45 °C) Ωcm 1200 1200 1300 1200 1200 1300
Specific conductivityσ15 ≤(atϑµS/cm 833 833 770 833 833 770
Max. mains impedance at 50Hz Ω0.284 0.270 0.260 0.254 0.241
Connections
Water connection G 1/2 A G 1/2 A
Application limits
Max. permissible pressure MPa 1.0 1.0
Max. inlet temperature for reheating °C 45 45
Values
Max. permissible inlet temperature °C 65 65
ON l/min >2.5 >2.5
Flow rate for pressure drop l/min 5.2/6.0/6.9 7.7
Pressure drop at flow rate MPa 0.08/0.10/0.13 (0.06/0.08/0.10 without DMB) 0.16 (0.12 without DMB)
Flow rate limit at l/min 12 (7.5) 12 (7.5)
DHW delivery l/min 9.2/10.7/12.3 13.3
Δϑ at DHW delivery K 28 28
Hydraulic data
Rated capacity l 0.4 0.4
Versions
Connected load options X -
Temperature adjustment °C 30-60 30-60
Protection class 1 1
Insulation block Plastic Plastic
Heating system heat generator Bare wire Bare wire
Cap and back panel Plastic Plastic
Colour white white
IP-Rating IP25 IP25
Dimensions
Height mm 478 478
Width mm 225 225
Depth mm 105 105
Weights
Weight kg 3.6 3.6
Guarantee
The warranty conditions of our German companies do not
apply to appliances acquired outside of Germany. In countries
where our subsidiaries sell our products, it is increasingly the
case that warranties can only be issued by those subsidiaries.
Such warranties are only granted if the subsidiary has issued
its own terms of warranty. No other warranty will be granted.
We shall not provide any warranty for appliances acquired in
countries where we have no subsidiary to sell our products.
Environment and recycling
We would ask you to help protect the environment. After use,
dispose of the various materials in accordance with national
regulations.

Deutschland
STIEBEL ELTRON GmbH & Co. KG
Dr.-Stiebel-Straße 33 | 37603 Holzminden
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.de
Verkauf Tel. [phone] | Fax [phone] | [email protected]
Kundendienst Tel. [phone] | Fax [phone] | [email protected]
Ersatzteilverkauf Tel. [phone] | Fax [phone] | [email protected]
Irrtum und technische Änderungen vorbehalten! | Subject to errors and technical changes! | Sous réserve
d‘erreurs et de modifications techniques! | Onder voorbehoud van vergissin gen en technische wi jzigingen! |
Salvo error o modificación técnica! | Excepto erro ou alteração técnica | Zastrzeżone zmiany techniczne i
ewentualne błędy | Omyly a technické změny jsou vyhrazen y! | A muszaki változta tások és tévedések jogát
fenntartjuk! | Отсутствие ошибок не гарантируется. Возможны технические изменения. | Chyby a
technické zmeny sú vyhradené! Stand 9030
Australia
STIEBEL ELTRON Australia Pty. Ltd.
6 Prohasky Street | Port Melbourne VIC 3207
Tel. [phone] | Fax [phone]
[e-mail]
www.stiebel.com.au
Austria
STIEBEL ELTRON Ges.m.b.H.
Eferdinger Str. 73 | 4600 Wels
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.at
Belgium
STIEBEL ELTRON bvba/sprl
't Hofveld 6 - D1 | 1702 Groot-Bijgaarden
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.be
China
STIEBEL ELTRON (Guangzhou) Electric Appliance
Co., Ltd.
Rm 102, F1, Yingbin-Yihao Mansion, No. 1
Yingbin Road
Panyu District | 511431 Guangzhou
Tel. [phone] | Fax [phone]
[e-mail]
www.stiebeleltron.cn
Czech Republic
STIEBEL ELTRON spol. s r.o.
K Hájům 946 | 155 00 Praha 5 - Stodůlky
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.cz
Denmark
Pettinaroli A/S
Mandal Allé 21 | 5500 Middelfart
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.dk
Finland
STIEBEL ELTRON OY
Kapinakuja 1 | 04600 Mäntsälä
Tel. [phone]
[email protected]
www.stiebel-eltron.fi
France
STIEBEL ELTRON SAS
7-9, rue des Selliers
B.P 85107 | 57073 Metz-Cédex 3
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.fr
Hungary
STIEBEL ELTRON Kft.
Gyár u. 2 | 2040 Budaörs
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.hu
Japan
NIHON STIEBEL Co. Ltd.
Kowa Kawasaki Nishiguchi Building 8F
66-2 Horikawa-Cho
Saiwai-Ku | 212-0013 Kawasaki
Tel. [phone] | Fax [phone]
[email protected]
www.nihonstiebel.co.jp
Netherlands
STIEBEL ELTRON Nederland B.V.
Daviottenweg 36 | 5222 BH 's-Hertogenbosch
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.nl
Poland
STIEBEL ELTRON Polska Sp. z O.O.
ul. Działkowa 2 | 02-234 Warszawa
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.pl
Russia
STIEBEL ELTRON LLC RUSSIA
Urzhumskaya street 4,
building 2 | 129343 Moscow
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.ru
Slovakia
TATRAMAT - ohrievače vody s.r.o.
Hlavná 1 | 058 01 Poprad
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.sk
Switzerland
STIEBEL ELTRON AG
Industrie West
Gass 8 | 5242 Lupfig
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.ch
Thailand
STIEBEL ELTRON Asia Ltd.
469 Moo 2 Tambol Klong-Jik
Amphur Bangpa-In | 13160 Ayutthaya
Tel. [phone] | Fax [phone]
[email protected]
www.stiebeleltronasia.com
United Kingdom and Ireland
STIEBEL ELTRON UK Ltd.
Unit 12 Stadium Court
Stadium Road | CH62 3RP Bromborough
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron.co.uk
United States of America
STIEBEL ELTRON, Inc.
17 West Street | 01088 West Hatfield MA
Tel. [phone] | Fax [phone]
[email protected]
www.stiebel-eltron-usa.com
A 313147-38680-9041
4 017213 131472