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
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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.
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Appliance description

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ENGLISH
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
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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
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- 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
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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.
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Seal and insert the twin connectors.
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2
3
1
3
1 Cold water with 3-way ball shut-off valve
2 DHW with tee
3 Gasket
Fit the water connections.
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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.
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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: