STIEBEL ELTRON DEL 27 AU 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 �����������������������������������������3
1.1 Safety instructions����������������������������������������������� 3
1.2 Other symbols in this documentation ����������������������� 3
1.3 Units of measurement ������������������������������������������ 3
2. Safety����������������������������������������������������������4
2.1 Intended use������������������������������������������������������ 4
2.2 General safety instructions ������������������������������������ 4
2.3 CE designation ��������������������������������������������������� 4
2.4 Test symbols ������������������������������������������������������ 4
3. Appliance description ���������������������������������������4
4. Settings and displays ����������������������������������������5
4.1 User interface ���������������������������������������������������� 5
4.2 Temperature limit (childproofing)���������������������������� 5
4.3 Inlet temperature information �������������������������������� 6
4.4 Following an interruption of the water supply ������������ 6
5. Cleaning, care and maintenance ���������������������������6
6. Troubleshooting ����������������������������������������������6
INSTALLATION
7. Safety����������������������������������������������������������7
7.1 General safety instructions ������������������������������������ 7
7.2 Instructions, standards and regulations �������������������� 7
8. Appliance description ���������������������������������������7
8.1 Standard delivery������������������������������������������������ 7
9. Preparations ��������������������������������������������������7
9.1 Installation site��������������������������������������������������� 8
10. Installation����������������������������������������������������8
10.1 Standard installation�������������������������������������������� 8
10.2 Completing the installation����������������������������������� 10
10.3 Installation options��������������������������������������������� 11
11. Commissioning ��������������������������������������������� 13
11.1 Initial start-up��������������������������������������������������� 13
11.2 Recommissioning����������������������������������������������� 14
12. Shutting down the system �������������������������������� 14
13. Troubleshooting �������������������������������������������� 14
13.1 Service mode ���������������������������������������������������� 14
13.2 Indicator options for LED diagnostic traffic light ��������� 15
13.3 Fault table�������������������������������������������������������� 15
14. Maintenance ������������������������������������������������ 16
15. Specification ������������������������������������������������ 16
15.1 Dimensions and connections��������������������������������� 16
15.2 Wiring diagram ������������������������������������������������� 17
15.3 DHW output ����������������������������������������������������� 17
15.4 Application areas/ conversion table ����������������������� 17
15.5 Pressure drop ��������������������������������������������������� 17
15.6 Fault conditions ������������������������������������������������� 17
15.7 Data table �������������������������������������������������������� 18
WARRANTY | ENVIRONMENT AND RECYCLING
SPECIAL INFORMATION
- The appliance may be used by children aged 8
and up and persons with reduced physical, sen-
sory or mental capabilities or a lack of experience
and know-how, provided that they are supervised
or they have been instructed on how to use the
appliance safely and have understood the result-
ing risks. Children must never play with the ap-
pliance. Children must never clean the appliance
or perform user maintenance unless they are
supervised.
- Ensure the appliance can be separated from the
power supply by an isolator that disconnects all
poles with at least 3mm contact separation.
- Secure the appliance as described in chapter "In-
stallation/ Installation".
- Observe the maximum permissible pressure (see
chapter "Specification/ Data table").
- Drain the appliance as described in chapter "In-
stallation/ Maintenance/ Draining the appliance".

OPERATION
General information
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OPERATION
1. General information
The chapter "Operation" is intended for appliance users and qual-
ified 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 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-seri-
ous 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 ac-
tion you need to take is described step by step.
1.3 Units of measurement
Note
Unless specified otherwise, all dimensions are given in
mm.

OPERATION
Safety
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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-do-
mestic 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 inappropri-
ate. 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 ex-
cess of 43 °C.
!
WARNING Injury
The appliance may be used by children aged 8 and up and
persons with reduced physical, sensory or mental capa-
bilities 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.
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
qualified contractor:
- The temperature limit (childproofing) 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
Information for Australia/New Zealand:
Installation complies with standard AS/NZS 3500.4.
3. Appliance description
The electronically controlled instantaneous water heater with
automatic output matching maintains a consistent outlet tem-
perature. 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 select-
ed temperature is displayed.
Display backlighting
The display has white backlighting. During the draw-off process
or a temperature adjustment, backlighting is enabled.
Temperature limit (childproofing)/ anti-scalding protection
You can set the temperature limit (childproofing) individually 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 pro-
tection from 43°C 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 the temperature limit (childproofing).
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 that large-
ly prevents damage to the heating system. If, during op-
eration, air is drawn into the appliance, heating output
is shut down automatically for one minute, thereby pro-
tecting the heating system.

OPERATION
Settings and displays
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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
5 Temperature limit Tmax
Display symbols
1
2
3
4
D0000040989
1 In the event of an appliance fault, a spanner appears
2 Segment display for temperature setting with °C
3 Performance bar, 10 - 100%
4 Tmax, displayed when temperature limit is enabled
Setting the temperature
M1 Tmax M2
D0000040726
2
1
3
1 Set temperature setting range 30 - 60°C (without end-stop)
35°C ... 43°C in 0.5°C increments, other temperature ranges
in 1°C increments
2 Call up preferred temperatures
3 Set the temperature limit
Memory keys M1 and M2 can each be assigned a preferred tem-
perature.
 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 preferred temperature delivery is achieved.
4.2 Temperature limit (childproofing)
M1 Tmax M2
D0000040981
The temperature limit can be individually set between 30°C and
50°C.
Enabling the temperature limit (childproofing)
 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 (childproofing)
 Press and hold the Tmax key for >6seconds.
 The Tmax symbol on the display is no longer shown.

OPERATION
Cleaning, care and maintenance
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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 alter-
nates 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 of the water supply
!
Material losses
Following an interruption of the water supply the appli-
ance must be recommissioned by carrying out the follow-
ing 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 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/distribution
panel.
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 / Follow-
ing 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 au-
tomatically after 1minute.
The temperature at
the appliance cannot
be set to >43°C.
The Tmax childproofing is
enabled.
Disable the childproofing
(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 ... AU
26�02�02�1125�

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INSTALLATION
Safety
INSTALLATION
7. Safety
Only a qualified contractor should carry out installation, commis-
sioning, 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
For the thermostatic valve to function correctly, the flow
limiter for this valve must not be replaced with the plastic
profile washer.
!
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.
7.2 Instructions, standards and regulations
Note
Observe all applicable national and regional regulations
and instructions.
- 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 plugs
- 2 extensions
- 2 caps
- 2 tees
- 8 flat gaskets
- Strainer
- 2 flow limiters
- Plastic profile washer
- Plastic connection pieces / installation aid
- Cover and back panel guides
9. Preparations
 Flush the water line thoroughly.
Taps/valves
 Use appropriate pressure-tested taps. Open taps are not
permitted.
A safety valve is not required.
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 pres-
sure (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.

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INSTALLATION
Installation
9.1 Installation site
!
Material losses
Only install the appliance in rooms free from the risk of
frost.
 Always install the appliance vertically 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 pipe
2 DHW outlet pipe
10. Installation
10.1 Standard installation
- Electrical connection in the lower section of the appliance for
installation on unfinished walls
- Water connection for installation on finished walls
- For the appliance with adjustable connected load, the middle
load is preset.
For further installation options, see chapter "Installation options".
electronic comfor t
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�
 Mount the wall mounting bracket.
Align the installation template based on the existing electrical
connection when marking out the drill holes (wall mounting and
lower back panel).
If you want to adapt the existing water connections, take the di-
mensions from the drawing when marking out the drill holes; see
chapter "Specification/ Dimensions and connections". In this case,
check beforehand that the electrical connection lies within one of
the areas marked on the installation template.

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INSTALLATION
Installation
160
30
1
26�02�02�0824�
1 Installation aid
 Prepare the power cable.
Preparing the water connection
!
Material losses
Carry out all water connection and installation work in
accordance with regulations.
D0000041720
 Remove the caps from the tees.
 Fit the plugs and the extensions with gaskets.
D0000041721
 Fit the strainer in the tee for the cold water inlet.
!
Damage to the appliance and environment
The strainer must be fitted for the appliance to function.
 When replacing the appliance, check that the strain-
er is present.
D0000041722
12
1 Flow limiter
2 Plastic profile washer
 Fit the flow limiter or the plastic profile washer.
Note
 Install the blue flow limiter (7.5l/min) as standard.
 Use the brown flow limiter (12l/min) in the follow-
ing instances:
- 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 be-
hind, 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.

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INSTALLATION
Installation
D0000041723
 Screw the pre-assembled parts with flat gaskets to the cold
water and DHW pipes of the appliance.
 Fit the cold water inlet pipe and the DHW outlet pipe from
the pipework with flat gaskets to the extensions from the
appliance.
Making the electrical connection
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 dis-
connects all poles with at least 3mm 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.
Lower back panel installation
1
2
26�02�02�1080
1 Connection pieces delivered in the pack
2 Screw
 Cut open the lower part of the back panel (see illustration).
 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.
 Align the mounted appliance by loosening the fixing toggle,
aligning the power supply and back panel, and then re-tight-
ening the fixing toggle.
 Secure the lower back panel with a screw.
10.2 Completing the installation
 Open the shut-off valve in the cold water inlet line.
Fitting the sealing elements for the appliance cover
1
2
3
D0000040777
1 Pipe aperture
2 Cover guides
3 Back panel guides
!
Material losses
If you cut open the wrong knock-out in the appliance
cover by mistake, you must use a new appliance cover.
 Cleanly cut or break out the knock-out openings in the appli-
ance cover. If necessary, use a file.
Note
You can compensate for a slight connection pipe offset
using the tabs on the cover guides. If the connection pipes
are offset, do not fit any back panel guides.