STIEBEL ELTRON LWZ 304 Integral User manual

INSTALLATION
Central ventilation unit with heat recovery
» LWZ304Integral
» LWZ304Trend
» LWZ404Trend

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CONTENTS
SPECIAL INFORMATION
INSTALLATION
1. General information �����������������������������������������3
1.1 Relevant documents_____________________________________________ 3
1.2 Standardised output data ______________________________________ 3
2. Safety����������������������������������������������������������3
2.1 General safety instructions ____________________________________ 3
2.2 Instructions, standards and regulations ____________________ 4
2.3 Operation of the appliance in buildings with
combustion equipment _________________________________________ 4
3. Appliance description ���������������������������������������5
3.1 Standard delivery________________________________________________ 5
3.2 Required accessories ___________________________________________ 5
3.3 Additional accessories __________________________________________ 5
3.4 Appliance functions _____________________________________________ 5
4. Preparations ��������������������������������������������������6
4.1 Installation site___________________________________________________ 6
4.2 Air routing ________________________________________________________ 7
4.3 Sound emissions_________________________________________________ 7
4.4 Electrical installation____________________________________________ 8
4.5 Oxygen diffusion_________________________________________________ 9
4.6 Transport __________________________________________________________ 9
5. Installation����������������������������������������������������9
5.1 Siting the function module ____________________________________ 9
5.2 Installing the cylinder module _______________________________ 11
5.3 Connecting modules ___________________________________________ 12
5.4 Heating water connection_____________________________________ 14
5.5 Water connection _______________________________________________ 15
5.6 Filling the DHW cylinder ______________________________________ 15
5.7 Filling and venting the heating system_____________________ 16
5.8 Electrical connection___________________________________________ 17
5.9 Fitting the appliance casing __________________________________ 20
5.10 Outdoor air and exhaust air hose installation ____________ 21
5.11 Installing extract air and supply air pipes _________________ 22
6. Commissioning ��������������������������������������������� 23
6.1 Checks before commissioning________________________________ 23
6.2 Commissioning__________________________________________________ 24
6.3 Recommissioning_______________________________________________ 26
7. Settings ����������������������������������������������������� 26
7.1 Menus and parameters________________________________________ 26
 INFO _______________________________________________________________ 26
 DIAGNOSIS _______________________________________________________ 26
 PROGRAMS ______________________________________________________ 26
 STANDARD SETTING____________________________________________ 26
 SETTINGS_________________________________________________________ 26
 HEATING __________________________________________________________ 26
 DHW _______________________________________________________________ 27
 VENTILATION ____________________________________________________ 29
 DRY HEATING PROGRAM ______________________________________ 31
 COMMISSIONING________________________________________________ 31
 CONTRACTOR ____________________________________________________ 32
 ENTER CODE _____________________________________________________ 32
 FAULT SEARCH___________________________________________________ 32
 SWITCH ON MANUALLY ________________________________________ 32
 EVAPORATOR ____________________________________________________ 32
 REFRIGERATION UNIT__________________________________________ 33
 PUMPS ____________________________________________________________ 33
 PUMP CYCLES____________________________________________________ 33
 EMERGENCY MODE AUTO _____________________________________ 33
 POWER-OFF______________________________________________________ 33
 PROCESS VALUES _______________________________________________ 33
 PROCESS STATUS _______________________________________________ 34
 ANALYSIS _________________________________________________________34
7.2 Economy settings _______________________________________________34
8. Appliance shutdown ��������������������������������������� 35
9. Troubleshooting �������������������������������������������� 35
9.1 Exhaust air fan is catching____________________________________ 35
9.2 Cleaning defrost pan___________________________________________ 36
9.3 Circulation pump _______________________________________________ 36
9.4 Fault messages in the programming unit _________________ 36
10. Maintenance and cleaning �������������������������������� 40
10.1 Cleaning the air/air heat exchanger ________________________ 40
10.2 Cleaning the outdoor air filter _______________________________ 40
10.3 Cleaning the evaporator fins _________________________________ 40
10.4 Cleaning the condensate drain_______________________________ 41
10.5 Cleaning the filter ball valve__________________________________ 42
10.6 Replacing the anode ___________________________________________ 42
11. Specification ������������������������������������������������ 43
11.1 Dimensions and connections_________________________________ 43
11.2 Connection examples __________________________________________44
11.3 Wiring diagram _________________________________________________ 45
11.4 Output diagram _________________________________________________48
11.5 Fan curve _________________________________________________________ 49
11.6 Pump curve ______________________________________________________ 50
11.7 Application range_______________________________________________ 50
11.8 Sensor resistance values ______________________________________ 51
11.9 Data table ________________________________________________________ 52

ENGLISH
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SPECIAL INFORMATION | INSTALLATION
General information
SPECIAL INFORMATION
- Observe all applicable national and regional reg-
ulations and instructions during installation.
- The appliance is not approved for outdoor
installation.
- Observe the requirements concerning the instal-
lation room (see chapter "Specification/ Data
table").
- Observe minimum clearances (see "Preparations/
Installation site").
- The connection to the power supply must be in
the form of a permanent connection. Ensure the
appliance can be separated from the power sup-
ply by an isolator that disconnects all poles with
at least 3mm contact separation.
- Observe the MCB/fuse protection required for
the appliance (see chapter "Specification/ Data
table").
- Drain the appliance as described in chapter
"Shutdown".
- Install a type-tested safety valve in the cold water
supply line.
- The maximum pressure in the cold water supply
line must be at least 20% below the response
pressure of the safety valve. If the maximum
pressure in the cold water supply line is higher,
install a pressure reducing valve.
- Size the drain so that water can drain off unim-
peded when the safety valve is fully opened.
- Fit the discharge pipe of the safety valve with
a constant downward slope and in a room free
from the risk of frost.
- The safety valve discharge aperture must remain
open to atmosphere.
INSTALLATION
1. General information
These instructions are intended for qualified contractors.
1.1 Relevant documents
317238 LWZ 304-404 Trend/Integral Operation
1.2 Standardised output data
Explanations to determine and interpret the specified standardised
output data
1.2.1 Standard: EN 13141-7, EN 14511, EN 16147
The output data specifically mentioned in text, diagrams and
technical datasheets has been calculated according to the test
conditions of the standard shown in the heading of this section.
Generally, these standardised test conditions will not fully meet
the conditions found at the installation site of the system user.
Depending on the chosen test method and the extent to which
this method deviates from the conditions defined in the norm
shown in the heading of this section, any deviations can have a
considerable impact.
Additional factors that have an influence on the test values are the
measuring equipment, the system configuration, the age of the
system and the flow rates.
A confirmation of the specified output data can only be obtained
if the test conducted for this purpose is also performed in ac-
cordance with the conditions defined in the norm shown in the
heading of this section.
2. Safety
Only a qualified contractor should carry out installation, commis-
sioning, maintenance and repair of the appliance.
2.1 General safety instructions
We guarantee trouble-free function and operational reliability only
if original accessories and spare parts intended for the appliance
are used.
2.1.1 Electrical installation
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with national and regional regulations.
WARNING Electrocution
Isolate the appliance from the power supply prior to
commencing any work in the interior of the appliance.

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INSTALLATION
Safety
WARNING Electrocution
The connection to the power supply must be in the form
of a permanent connection. The appliance must be able
to be separated from the power supply by an isolator
that disconnects all poles with at least 3mm contact
separation. This requirement can be met by contactors,
isolators, fuses, etc.
!
Material losses
The specified voltage must match the mains voltage. Ob-
serve the type plate.
2.2 Instructions, standards and regulations
Note
Observe all applicable national and regional regulations
and instructions.
WARNING Burns
In connection with the fire prevention regulations con-
cerning the installation of ventilation systems, observe
all country-specific regulations and requirements. In
Germany, these are particularly the building regulation
guideline on fire prevention requirements of ventilation
systems in its applicable issue.
2.3 Operation of the appliance in buildings with
combustion equipment
If the building contains combustion equipment (tiled stoves, fire-
places, etc.), the responsible flue gas inspector must be consulted
in the planning phase. The flue gas inspector assesses whether
all statutory regulations are being observed. Here, a differenti-
ation is made between room sealed and open flue combustion
equipment. For simultaneous operation of combustion equipment
and a mechanical ventilation system, we recommend choosing
approved room sealed combustion equipment (in Germany with
DIBt approval).
2.3.1 Room sealed combustion equipment
In conjunction with room sealed combustion equipment, no addi-
tional precautions are generally required. Assessment is carried
out by the flue gas inspector.
2.3.2 Open flue combustion equipment
!
WARNING – Injury
If open flue combustion equipment is operated with the
mechanical ventilation system, tested safety equipment
must be installed. The combustion equipment must also
have a separate combustion air supply.
With open flue combustion equipment, a differentiation must be
made between alternate and simultaneous operation of the ven-
tilation system and combustion equipment.
Alternate operation
Operation on alternate sides means that, when the combustion
equipment is commissioned, the mechanical ventilation system is
switched off and cannot be started.
Note
Operation on alternate sides is not recommended be-
cause, in this case, central heating and DHW heating are
carried out by the electric emergency/booster heater.
Simultaneous operation
!
WARNING – Injury
Ensure that no flue gas can enter the installation room
and that combustion equipment will always be supplied
with sufficient combustion air. Tested safety equipment
must be installed to monitor the chimney draught and
to switch off the ventilation unit in the event of a fault.
The equipment for differential pressure monitoring should fulfil
the following requirements:
- Monitoring of the differential pressure between the connec-
tion piece to the chimney and the room where the combus-
tion equipment is installed.
- Possibility of matching the shutdown value for the differential
pressure to the minimum draught requirement for the com-
bustion equipment.
- Floating contact to switch off the ventilation or heat pump
function.
- Optional connection of a temperature capturing device so
that differential pressure monitoring is only enabled when
the combustion equipment is in operation and so that un-
wanted shutdowns due to environmental influences can be
avoided.
Note
Differential pressure switches that use the pressure
differential between the outdoor air pressure and the
pressure in the room where the combustion equipment
is sited as a response criterion are not suitable.
 Connect the safety equipment with a floating contact to ter-
minal X4-13/14 (contact “Oven / fireplace”). We recommend
installing a 5-core cable between the combustion equipment
and the ventilation unit.
Triggering the safety equipment may shut down the domestic ven-
tilation system and block the integral heat pump of the appliance.
You can determine how the appliance will behave following a
triggering of the safety equipment using the "OVEN / FIREPLACE"
parameter.
If you want the entire appliance to be switched off when the safety
equipment is triggered, you can integrate the safety of equipment
in the same way as an underfloor heating system thermostat (see
chapter "Specification/ Connection examples").

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INSTALLATION
Appliance description
As the appliance in the installation room can produce negative
pressure, we recommend using a tightly sealing door between the
installation room and the living space for operation with combus-
tion equipment. If, due to its use, the installation room is connect-
ed to the extract air system, you must also allow for a supply air
valve in the installation room in this particular case to prevent any
further increase in the negative pressure in the installation room.
The negative pressure created by the appliance in the installation
room is heavily influenced by the pressure drop in the outdoor
air line. For this reason, the outdoor air line in particular should
be as short as possible.
Note
The maximum permissible pressure drop (see chapter
"Specification/ Data table/ Max. pressure drop, outdoor
air") must not be exceeded.
3. Appliance description
The appliance comprises a function module and a cylinder module
that are supplied as separate shipping units. The wider module
with the air hose connections in the cover is the function module.
The components required for installation are in a separate carton
inside the function module packaging.
3.1 Standard delivery
Note
Never install the push-fit connectors in the DHW line.
Only install the push-fit connectors in the heating circuit.
The following are delivered with the appliance:
- Operating instructions
- Installation instructions
- Programming unit
- Outside temperature sensor
- Four adjustable feet for the cylinder module
- Eight sliding blocks for easier positioning of the appliance
- Hose clips to secure the air hoses
- Adhesive tape to seal the inner hose to the hose connector
- PE plate for connection to a geothermal heat exchanger or an
external fresh air intake
- Fixing materials (screws, washers, etc.)
- Three straight push-fit connectors for the hydraulic connec-
tion of the function and cylinder modules
For connection to the heating circuit:
- Two straight push-fit connectors
- One filter ball valve
- One ball valve
- Two 90° push-fit connectors
- Four straight pieces of pipe with G1 union nut
3.2 Required accessories
- Air hose with thermal insulation, 4m
- Thermally insulated wall outlet with external wall grille
3.3 Additional accessories
- Transport aid (233485)
- Additional programming unit with wall mounted casing
- Spare filter set
- Diverter hood (enables the appliance to be sited in rooms
with <2.2m head height)
- Silencer DN315
- Relay set WPM-RBS
- Segmented anode
- Starting current limiter 25A (part number 281546)
- DHW circulation pipe set
- Filter box (for installation in round DN160 ventilation pipes)
- Internet Service Gateway ISG (not for LWZ304Integral)
- PK10 condensate pump
3.4 Appliance functions
The supply air fan induces outdoor air into the appliance. The
extract air fan draws stale air from the living areas into the appli-
ance. Outdoor air and extract air are routed through particle air
filters into separate ducts of a cross-countercurrent heat exchang-
er. Inside the cross-countercurrent heat exchanger, the outdoor
air is heated and channelled into the living space as supply air.
The extract air cools down inside the cross-countercurrent heat
exchanger and is routed as exhaust air first through the evaporator
and then outdoors.
The cross-countercurrent heat exchanger ensures that up to 90%
of the heat in the extract air is returned with the supply air into
the living space.
In addition, heat is extracted from the outdoor air by means of an
air source heat pump. The energy extracted from the outdoor air
in the evaporator is transferred via the condenser to the central
heating or DHW system.
In the case of low outside temperatures or high heat demand
from the central heating or DHW heating systems, the additional
heat demand is covered by an electric emergency/booster heater.
3.4.1 Frost protection for the cross-countercurrent heat
exchanger
A heat exchanger in the path of the outdoor air flow preheats
the outdoor air, and thus prevents the cross-countercurrent heat
exchanger from freezing up.
3.4.2 Buffer mode for air heating
If a heating system with a low draw-off rate and little thermal
capacity is used, e.g. air heating coil through which the domestic
ventilation flow is routed, the lower section of the DHW cylinder
can be utilised as a buffer cylinder.
Excess heat can be temporarily stored there, thereby reducing
compressor cycling. This function can be activated in the "DHW"
menu using the "DHW BUFFER MODE" parameter.

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INSTALLATION
Preparations
You can determine the operating mode by positioning the cylinder
temperature sensor.
1
2
D0000039615
1 Cylinder temperature sensor - upper position
2 Cylinder temperature sensor - lower position
If the cylinder temperature sensor is in the upper position, ap-
prox. 100l water are always maintained at the required DHW
temperature. The remaining cylinder capacity is used as a heating
buffer and have a temperature corresponding to the heating flow
temperature.
If the cylinder temperature sensor is in the lower position, the
entire cylinder content is always maintained at the required DHW
temperature.
4. Preparations
4.1 Installation site
To be able to open the front door freely, maintain a minimum
clearance on the r.h. side and in front of the appliance.
The required room height depends on whether the reversing hood
is used or whether the hoses are connected directly (see chapter
"Installation site/ Minimum clearances").
Maintain a minimum clearance on the r.h. side of the appliance
for service work.
Never install the appliance in wet rooms.
The room in which the appliance is to be installed must meet the
following conditions:
- The room must be free from the risk of frost.
- The floor must have sufficient load-bearing capacity. In ad-
dition to the appliance weight, also take that of the cylinder
content into account.
- The substrate must be horizontal, level, solid and permanent.
- When installing the appliance inside a boiler room ensure
that the boiler operation is not impaired.
- The quantity of refrigerant makes it necessary to observe
the minimum volume of the installation room (see chapter
"Specification/ Data table").
!
Material losses
The installation room floor must be water resistant. Dur-
ing appliance operation, the outdoor air releases up to
50l of condensate per day. If the condensate drain is not
installed correctly or if maintenance is not carried out
properly, water may escape. We recommend installing a
drain in the floor of the installation room.
4.1.1 Minimum clearances
Outdoor/exhaust air connection with diverter hood
≥2200
1980
≥500
≥100
≥600
D0000039681

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INSTALLATION
Preparations
Outdoor/exhaust air connection with air hose
≥2500
2255
≥500
R 365
≥600
≥100
D0000039682
Connecting outdoor air to geothermal heat exchanger
≥300
≥2°
D0000039683
1
1 Filter box
Outdoor air domestic ventilation connection option
≥300
≥1000
D0000039684
1
1 Filter box
4.2 Air routing
Prevent air stream "short circuits". The air intake and discharge
apertures in the external walls should be arranged around cor-
ners. When installing the air intake and discharge apertures on
the same side of the building, maintain a minimum clearance of
at least 2m between apertures. Where that is impossible, create
a separation between the air streams, e.g. by a separating wall or
shrubs between the intake and discharge apertures.
Never align the apertures toward neighbouring living room or
bedroom windows.
4.3 Sound emissions
Sound insulation for rooms adjacent to the installation room
When the appliance is in operation, sound emissions can occur
which may be a nuisance in adjacent rooms. This is especially the
case if the installation room adjoins a living room or bedroom. To
prevent noise pollution, sound attenuation measures are neces-
sary, e.g. sound attenuation of a higher standard for the internal
wall. Pipe fixings and wall outlets must have anti-vibration insu-
lation. For the wall between the installation room and the living
space, we recommend a wall structure that ensures the following
level of sound attenuation:
- 45 dB(A) for adjacent living rooms and bedrooms
- 40 dB(A) for other rooms
Doors should be of sound safety category SK3.
If the appliance backs onto an adjacent room, we recommend the
following level of sound attenuation:
- 55 dB(A) for adjacent living rooms and bedrooms
- 50 dB(A) for other rooms
A passage to the neighbouring room is not recommended.

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INSTALLATION
Preparations
The floor between the installation room and living areas must
have carefully applied anti-vibration separation. Ensure that no
pipes are routed on or in the wall and that the air ducts have
anti-vibration separation.
If the appliance installation room is included in the building ven-
tilation system, an extract air valve and supply air valve must be
planned in. To avoid the need for an overflow aperture in the
door, the supply air and extract air flow rates must be balanced.
Note
The appliance can seem loud if operated in an unfinished
building without doors. This is because the fixtures and
fittings are not yet in place which will provide sound at-
tenuation; once the building is occupied this should no
longer occur.
Sound attenuation 45dB(A)
Sound attenuation of 45dB(A) can be achieved using, for ex-
ample, a lightweight wall of timber frame construction with full
insulation. The cross-section of the timber supports should be
60x60mm. The wall must have plasterboard panelling on both
sides, with a thickness of 12.5mm on one side and 10mm on the
opposite side.
2
1
3
3
2
D0000047127
1 Timber supports 60 x 60mm
2 Gypsum fibre board 12.5 mm
3 Gypsum fibre board 10 mm
Sound attenuation 55dB(A)
Sound attenuation of 55dB(A) can be achieved using, for example,
a lightweight twin wall of timber frame construction with full in-
sulation and 30mm parting line. The cross-section of the timber
supports should be 60x60mm. The wall must have 12.5mm
plasterboard panelling on both sides.
3
13
3
3
2
D0000047126
1 Parting line 30mm
2 Timber supports 60 x 60mm
3 Gypsum fibre board 12.5 mm
Anti-vibration separation
With the anti-vibration feet, it is possible to install the appliance
on floating screed, as long as this has been applied correctly. If
necessary provide separation.
If the appliance is positioned on a wooden beam ceiling, you must
take special steps to prevent structure-borne noise transmission.
Installation on foundations
342
1
26_04_01_0290
1 Concrete base
2 Impact sound insulation
3 Floating screed
4 Screed recess
The separation can also be made later, by cutting the screed all
the way around the appliance.
Installation on screed with impact sound insulation
23
1
4
26_04_01_0291
1 Concrete base
2 Impact sound insulation
3 Floating screed
4 Screed recess
 Protect all pipe fixings and wall transitions with anti-vibra-
tion insulation.
4.4 Electrical installation
Permission must be obtained from your local power supply utility.
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with national and regional regulations.

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INSTALLATION
Installation
Electrical data is provided in the chapter "Specification/ Data
table". In accordance with the fuse protection, use the following
cable cross-sections when wiring:
MCB/fuse rating Cable cross-section
16 A 2.5 mm2
1.5 mm² with only two live cores and routing on a wall
or in an electrical conduit on a wall.
20 A 4.0 mm²
2.5 mm² when routing a multi core cable on a wall or in
an electrical conduit on a wall
Note
Route the power cables and control cables separately.
Note
Provide separate fuses for the power circuits for the ap-
pliance, the electric emergency/booster heater and the
control unit.
4.5 Oxygen diffusion
!
Material losses
Avoid open vented heating systems and underfloor heat-
ing systems with plastic pipes which are permeable to
oxygen.
In underfloor heating systems with plastic pipes that are per-
meable to oxygen and in open vented heating systems, oxygen
diffusion may lead to corrosion on the steel components of the
heating system (e.g.on the indirect coil of the DHW cylinder, on
buffer cylinders, steel radiators or steel pipes).
!
Material losses
The products of corrosion (e.g.rusty sludge) can set-
tle in the heating system components, which may re-
sult in a lower output or fault shutdowns due to reduced
cross-sections.
4.6 Transport
!
Material losses
If the appliance is transported without packing and with-
out using a pallet, its outer casing may be damaged.
Remove the side panels and doors in such cases.
4.6.1 Function module
To protect the appliance against damage, transport it vertically
inside its packaging. Where space is restricted, you can also tilt
the appliance at an angle to move it.
To make handling easier, you may attach a transport aid on the
back of the function module. This comprises two angled brackets.
 Fit one angle bracket each vertically on the l.h. and r.h. side.
26_04_01_0620_
1
1 Transport aids
 Slide a robust pipe through the holes inside the transport
aids to create a handle.
 The transport aid can also be used in connection with a
crane/hoist to transport the appliance to the installation
location.
4.6.2 Cylinder module
!
Material losses
During transport, never hold the cylinder module by its
connection pipes, as these would bend out of shape.
Note
We recommend the transport of the cylinder module on
its pallet to the installation location. The pallet offers
more places to hold than the cylinder module casing.
There are two grip recesses at the top of the back panel.
1
26_04_01_0638
1 Recessed grips
5. Installation
5.1 Siting the function module
!
Material losses
Never tilt the appliance excessively. Contacts between the
casing and the floor can damage the paintwork.
The fascia and fascia frame that are fitted to the front of the ap-
pliance later, hang for shipping from the factory on the l.h. side
of the function module.
 Remove the adhesive tape with which the fascia is secured
for transport.
 Remove the fascia from the function module.

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INSTALLATION
Installation
 Remove the wooden braces secured to the pallet which pre-
vented the appliance from slipping during shipping.
1
D0000039736
1 Door hinge bracket that attaches the side panel to the appli-
ance and holds the door
 Detach the door hinge bracket.
D0000039625
 Remove the door of the function module from the appliance.
 Remove the r.h. side panel of the function module.
 Remove the function module carefully from the pallet.
 Push the sliding blocks supplied under the adjustable feet,
so the function module can be moved more easily to the re-
quired position.
 Remove the sliding blocks once the appliance is in its intend-
ed location.
Outdoor air domestic ventilation connection option
Note
Observe the minimum clearance at the back of the ap-
pliance. See chapter "Preparations/ Installation site/
Minimum clearances".
1.
2.
3.
26_04_01_0613
1 Upper front panel
2 Cross-countercurrent heat exchanger
3 Outdoor air filter cassette
 Remove the upper front panel.
 Remove the round knock-out from the back panel of the
function module.
 Cut a hole for a folded spiral-seam tube DN160 in the centre
of the knock-out in the EPS thermal insulation.
 Push the folded spiral-seam tube through the hole
(max.30mm deep).
 Seal the gap between the folded spiral-seam tube and the
EPS insulation with sealing tape.
 Pull out the cross-countercurrent heat exchanger.
 Grasp the outdoor air filter cassette by the grip holes and
pull it out.
 Push the plate supplied into the appliance in place of the out-
door air filter cassette.
Note
Fit a filter in the outdoor air duct to replace the internal
outdoor air filter that was removed previously. An air
filter box with coarse particle filter mat is available as
an accessory.
Fit the joining bracket at the back at the bottom
26_04_01_0555
 Insert the joining bracket at the rear l.h. adjustable foot of
the function module between the appliance floor and the ad-
justable foot. Secure the joining bracket with two screws to
the back panel of the function module.
 Level the function module vertically by turning the height-ad-
justable feet.

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INSTALLATION
Installation
5.2 Installing the cylinder module
 Undo the screws underneath the pallet with which the cylin-
der module is secured to the pallet.
!
Material losses
Never tilt the cylinder module excessively. Contacts be-
tween the casing and the floor can damage the paint-
work.
1
2
3
26_04_01_0550
1 Captive nut on the bottom of the cylinder module
2 Adjustable foot with nut for fitting with an open-ended
spanner
3 Sliding block
 Carefully tip the cylinder module far enough to enable the
adjustable feet to be inserted.
 Insert the adjustable feet into the captive nuts with which the
cylinder module was previously secured to the pallet.
 Remove the cylinder module carefully from the pallet.
 Push the sliding blocks supplied underneath the adjustable
feet.
 Level the cylinder module vertically by turning the height-ad-
justable feet. Arrange the bottom panel so that it is 4 to
5mm higher than the bottom panel of the function module.
This is the amount by which the cylinder module drops when
it is being filled with water.
Note
The adjustable feet must not be fully screwed in, oth-
erwise you will not be able to push the joining bracket
between the bottom panel and the foot.
26_04_01_0552
 Undo the cover screws on the cylinder module.
 Reach through the port on the r.h. side of the cylinder mod-
ule and push the cylinder module cover upwards.
 Remove the cylinder module cover.
D0000039733
1
1 Fixing screw on the cylinder module front panel
 Undo the fixing screw on the cylinder module front panel.
D0000039647
1
24
3
1 Front panel of the cylinder module
2 DHW flow
3 Heating flow
4 Common return
 Lift the front panel of the cylinder module slightly and re-
move it from the cylinder module.
 Remove the plugs from the three pipes (DHW flow, heating
flow, common return); these are located in the lower sec-
tion on the r.h. side of the function module. Later on, these
pipes connect the function module and cylinder module
hydraulically.
Note
The pipes must protrude at least 40mm. If necessary,
remove any protruding foam insulation.
 Push a straight push-fit connector onto each of the three
pipes.
5.2.1 Pushing the cylinder module towards the function
module
 Push the cylinder module carefully towards the function
module, so that the rear r.h. adjustable foot of the cylinder
module is near the recess in the joining bracket.

12 | LWZ304 Trend | LWZ 404 Trend | LWZ 304 Integral www.stiebel-eltron.com
INSTALLATION
Installation
5.3 Connecting modules
Cylinder temperature sensor, anode cable, earth cable
 Remove the cable tie that ties together the electrical cables of
the anode terminal, the cylinder temperature sensor and the
earth cable.
 Pull the cable through the aperture that is located at the top
right-hand side of the cylinder module.
1
D0000039618
1 Aperture in the thermal insulation for sensor lead of the cyl-
inder temperature sensor
 Push the cylinder temperature sensor from the top through
the aperture in the thermal insulation.
 Insert the cylinder temperature sensor into the lower cylin-
der sensor well.
Note
It is possible that the cylinder module and the function
module will still be too far apart to be able to insert the
cylinder temperature sensor into the sensor sleeve.
If so, you can insert the cylinder temperature sensor into
the sleeve at a later point. What is important is that you
route the sensor lead through the insulation before you
install the terminal bracket.
The top sensor sleeve is required either in connection with buffer
operation on convector heaters (see chapter "Settings/ DHW/
DHW buffer mode") or for economy mode (see chapter "Connecting
internal cables").
Pushing the cylinder and the function modules together
Note
An air hose to capture the differential pressure runs
along the l.h. side of the function module. This air hose
must run inside the curved groove cut into the thermal
insulation.
 Ensure that this air hose is seated correctly.
Note
The adjustable feet must not be fully screwed in, oth-
erwise you will not be able to push the joining bracket
between the bottom panel and the foot.
 Push the cylinder module further towards the function mod-
ule, so that the rear r.h. adjustable foot of the cylinder mod-
ule is pushed into the recess in the joining bracket.
 The lower joining bracket ensures that the cylinder module
is automatically pushed into its final position. Level the cyl-
inder module and the function module vertically to the same
height by turning the adjustable feet.
Note
The cylinder module drops 4 to 5 mm when its cylinder
is filled.
Turning anti-clockwise exposes more of the adjustable feet, mean-
ing the appliance moves upwards. The cylinder module must be
snug against the function module.
D0000039619
1
3
2
2
1 Joining plates
2 Spacer
3 Horizontal locking bracket
Connection top back
 Connect the function module and the cylinder module at
the top back by positioning joining plates and inserting two
screws each through the joining plate into the function mod-
ule and the cylinder module.
Fitting the horizontal locking bracket to the front
 Connect the function module and cylinder module at the
front by securing one horizontal locking bracket each at the
top and bottom using screws. The spacers supplied enable
you to align the cylinder and function modules. Position a
spacer on the side of the function module, behind the upper
cross bolt and two spacers behind the lower cross bolt.

ENGLISH
www.stiebel-eltron.com LWZ 304 Trend | LWZ 404 Trend | LWZ 304 Integral | 13
INSTALLATION
Installation
!
Material losses
B efore filling, tighten the screws only lightly so that the
paint finish is not damaged when the cylinder module
moves down during filling. Tighten the screws after filling.
Connecting the function module and cylinder module
hydraulically
D0000039616
3
2
1
1 Door lock
2 Fixing screws of the lower front panel
3 High limit safety cut-out retaining bracket
A door lock is located above the door of the function module.
 Push the door lock at the front upwards.
 Pull the door lock backwards and then upwards to unhook
the door lock.
 Open the function module door.
 Undo the fixing screws from the lower front panel.
 Remove the lower front panel.
To make yourself room for the assembly, you can temporarily
unhook the high limit safety cut-out retaining bracket.
 Undo the screws on the high limit safety cut-out retaining
bracket.
 Unhook the high limit safety cut-out retaining bracket from
the slots, pull it out of the appliance and hook it into the
same slots, but this time from the outside.
D0000053516
1 2
3
1 DHW flow
2 Heating flow
3 Common return
The hydraulic connection between the function and cylinder
module is provided by three pipes: DHW flow, heating flow and
common return.
 Make sure that the caps have been removed from the pipes.
5.3.1 How the push-fit connectors work
!Material losses
Never install the push-fit connectors in the DHW line.
Only install the push-fit connectors in the heating circuit.
!Material losses
Tighten the screw cap of the push-fit connector by hand.
Never use a tool.
!Material losses
Support sleeves are required when using plastic pipes.
The push-fit connectors are equipped with a retainer with stain-
less steel serrations and an O-ring for sealing. The push-fit con-
nectors also have a "twist and secure" function. Simply turning
the screw cap by hand will secure the pipe in the connector and
push the O-ring against the pipe to seal it.
Making the push-fit connection
The connector must be in its relaxed position before the pipe is
inserted. In this position, there is a small gap between the screw
cap and connector body.
26_03_01_0693
3
1
24
1 Retainer
2 Screw cap
3 Gap between screw cap and connector body
4 Connector body

14 | LWZ304 Trend | LWZ 404 Trend | LWZ 304 Integral www.stiebel-eltron.com
INSTALLATION
Installation
26_03_01_0693
ØPipe diameter mm 22
AInsertion depth mm 38
!Material losses
Pipe ends must be deburred.
 Always use a pipe cutter to trim pipes.
 Push the pipe through the O-ring into the push-fit connector
until it reaches the prescribed insertion depth.
 Tighten the screw cap fully to the joiner body until fin-
ger-tight. This locks the push-fit connection.
Undoing the push-fit connection
If the push-fit connectors later need to be undone, proceed as
follows:
 Turn the screw cap anti-clockwise until a there is a narrow
gap of approx. 2mm. Press the retainer back with your fin-
gers and hold on to it.
 Pull out the inserted pipe.
26_03_01_0693
5.3.2 Connecting modules with push-fit connectors
An elbow push-fit connector is pre-fitted on the heating flow in
the function module.
 Fit the elbow push-fit connector onto the heating flow port
on the r.h. side of the cylinder module.
 Push a straight push-fit connector on each of the two pipes
on the r.h. side of the cylinder module.
 Connect both of the free pipes inside the function module to
the push-fit connectors that you previously attached to the
cylinder module pipes.
 Refit the high limit safety cut-out retaining bracket from the
inside using the slots and secure the bracket.
5.4 Heating water connection
The heating system must be connected by a qualified contractor in
accordance with the water installation drawings, which are part of
the technical guides. You can use the push-fit connectors supplied
or ball valves to make the connection of the flow and return.
Note
Deburr the pipe ends.
A filter ball valve is provided for the return. Two union nuts and
two short flanged copper pipe ends are provided for fitting a ball
valve.
 As a suitable point, install an air vent valve at the highest
point of the heating system.
 Thoroughly flush the pipework before connecting the ap-
pliance. Foreign bodies such as welding pearls, rust, sand,
sealant, etc. can impair the operational reliability of the ap-
pliance, and can lead to the condenser becoming blocked.
 Remove the protective caps from the heating flow and heat-
ing return connections.
"Heating return" connection
1
2
3
4
3
5
2
3
6
3
26_04_01_0629
1 "Heating return" connection
2 Plug-in connector
3 Flanged pipe
4 Filter ball valve
5 "Heating flow" connection
6 Ball valve
 Using a push-fit connector, connect one of the flanged pipes
supplied to the heating return connection.
 Connect the filter ball valve to the flanged pipe end.
 Reconnect a flared pipe to the end of the ball valve.
 Connect the flanged pipe with a push-fit connector to the
heating circuit return.
"Heating flow" connection
 Using a push-fit connector, connect one of the flanged pipes
supplied to the connection for the heating flow.
 Connect a ball valve to the flanged pipe end.
 Connect a flanged pipe to the other side of the ball valve.
 Connect the flanged pipe with a push-fit connector to the
heating circuit flow.

ENGLISH
www.stiebel-eltron.com LWZ 304 Trend | LWZ 404 Trend | LWZ 304 Integral | 15
INSTALLATION
Installation
Thermal insulation
 Provide thermal insulation in accordance with current
regulations.
Heating circuit water quality
Carry out a fill water analysis before filling the system. This may,
for example, be requested from the relevant water supply utility.
To avoid damage as a result of scaling, it may be necessary to
soften or desalinate the fill water. The fill water limits specified
in chapter "Specification/ Data table" must always be observed.
 Recheck these limits 8-12 weeks after commissioning and as
part of the annual system maintenance.
Note
With a conductivity > 1000 μS/cm, desalination treatment
is recommended in order to avoid corrosion.
Note
If you treat the fill water with inhibitors or additives, the
same limits apply as for desalination.
Note
Suitable appliances for water softening, as well as for
filling and flushing heating systems, can be obtained via
trade suppliers.
Minimum flow rate
The appliance is designed in such a way that no buffer cylinder
is required to provide hydraulic separation of the flow in the heat
pump circuit and the heating circuit in conjunction with area heat-
ing systems. If several heating circuits are used, we recommend
using a low loss header.
Note
The minimum flow rate must be maintained at every
operating point of the heat pump to ensure perfect heat
pump operation (see "Commissioning/ Commissioning").
To do this, the following options are available:
 Install a remote control in a lead room and open this
heating circuit fully.
 Install a low loss header or buffer cylinder.
The lead room is the room where the remote control is installed,
preferably the living room or bathroom. The lead room can be
regulated with an external programming unit, or indirectly by ad-
justing the heating curve. See chapter "Operation/ MAIN MENU/
SETTINGS/ HEATING" in the operating instructions.
If an underfloor heating thermostat is installed, it should be set
with a sufficient differential (at least 20K) from the maximum
set heating circuit temperature. The electrical connection of the
underfloor heating thermostat is shown in chapter "Specification/
Connection examples".
!
Material losses
In the "ACTUAL VALUES" menu, the appliance offers the
option to display the water pressure.
 Ensure that the pump does not run without water.
5.5 Water connection
!
Material losses
Never install the push-fit connectors in the DHW line.
Only install the push-fit connectors in the heating circuit.
Stainless steel, zinc-plated steel, copper or plastic pipework are
approved materials for the cold water line.
We approve stainless steel, copper or plastic pipework for the
DHW line.
 Remove the protective caps from the cold water inlet and
DHW outlet connections.
Safety valve
The appliance is a sealed unvented DHW cylinder. Provide the
appliance with a pressure relief valve.
 Install a type-tested safety valve in the cold water supply
line. The response pressure of the safety valve must be below
or equal to the permissible operating pressure of the DHW
cylinder.
The safety valve protects the appliance against unacceptable ex-
cess pressure. The diameter of the cold water supply line must be
no greater than the diameter of the safety valve.
 Ensure that the expansion water escaping from the safety
valve can drip into a drain, e.g. a tank or funnel.
Ensure the drain cannot be shut off.
 Size the drain so that water can drain off unimpeded when
the safety valve is fully opened.
 Ensure that the discharge pipe of the safety valve is open to
atmosphere.
 Fit the discharge pipe of the safety valve with a constant
downward slope and in a room free from the risk of frost.
Pressure reducing valve
Bear in mind that, depending on the static pressure, you may also
need a pressure reducing valve.
DHW circulation
DHW circulation is not recommended for reasons of poor energy
efficiency. If, however, DHW circulation is nevertheless required
because lines are routed awkwardly, it must always be designed
in accordance with applicable standards, i.e. with time and tem-
perature control. A DHW circulation set can be found in our range
of accessories.
5.6 Filling the DHW cylinder
The DHW cylinder can be filled via the cold water inlet connection.
 Open one or more hot water draw-off points to fill the DHW
cylinder.
 Close the hot water draw-off points once the cylinder is full.

16 | LWZ304 Trend | LWZ 404 Trend | LWZ 304 Integral www.stiebel-eltron.com
INSTALLATION
Installation
5.7 Filling and venting the heating system
1
D0000039056
1 Drain connection for filling and draining the heating circuit
 Undo the cap from the drain connection.
 Connect the fill hose.
1
D0000071354
1 Air vent valve on the multi function assembly
 Open the air vent valve of the multi function assembly by
turning anti-clockwise.
 After venting, check whether the air vent valve of the multi
function assembly drips.
1
D0000039621
1 Air vent valve of the DHW heating line
 Open the air vent valve of the DHW heating line.
 For filling, turn the lever on the drain connection 90°
anti-clockwise.
 Switch on the appliance and set the displayed system
pressure at the programming unit ("PRESSURE HTG CIRC"
parameter).
 Fill the system.
 After filling close the drain connection.
 Fit the cap on the drain connection.
You can check the water pressure in the heating circuit on the
programming unit with the "PRESSURE HTG CIRC" value.
 Determine the "PRESSURE HTG CIRC" value for one of the
three favourites. For this, navigate from the default display to
the "FAVOURITES" parameter.
WEDNESDAY 10.SEP 14 10:23 h
PRESSURE HTG CIRC
DHW TEMPERATURE
1.3 bar
35.0 °C
18.0 °CFLOW TEMPER ATUR E
DAY MODE
26_04_01_0292
Note
Proceed carefully when filling as the "PRESSURE HTG
CIRC" value is only updated every 10 seconds. If you
have determined the value not in association with one
of your favourites but instead by calling up the "ACTUAL
VALUES" parameter, the value will only be updated every
60sections.
Note
Air locks in the system are detrimental to the appliance
operation.
 Vent the pipework carefully.
5.7.1 Condensate drain
D0000039623
12
1 Condensate drain
2 Safety valve drain
On its r.h. side, the appliance is equipped with a condensate drain.
 Connect a condensate drain pipe to the condensate drain.
!
Material losses
To ensure the condensate drains perfectly, never kink the
hose. If necessary, create a loop.
 Route the condensate drain pipe with a sufficient
fall.

ENGLISH
www.stiebel-eltron.com LWZ 304 Trend | LWZ 404 Trend | LWZ 304 Integral | 17
INSTALLATION
Installation
Route the condensate into a floor drain. When doing so, ensure the
drain is adequately ventilated, e.g. free discharge into a siphon.
Use a condensate pump if there is insufficient fall.
 Check the position of the condensate pump in the function
module. The condensate pump must be lying entirely on the
floor.
Drain of the pressure relief valve
On the r.h. side of the appliance, the safety valve drain connection
also routes the pressure relief valve discharge hose out of the
casing. Ensure that draining water can run off freely.
5.8 Electrical connection
WARNING Electrocution
Only qualified electricians may carry out the connec-
tion in accordance with these instructions. Carry out all
electrical connection and installation work in accordance
with national and regional regulations.
WARNING Electrocution
Disconnect the appliance from the power supply before
carrying out work on the control panel.
WARNING Electrocution
The connection to the power supply must be in the form
of a permanent connection. The appliance must be able
to be separated from the power supply by an isolator
that disconnects all poles with at least 3mm contact
separation. This requirement can be met by using con-
tactors, circuit breakers, fuses/MCBs, etc.
!
Material losses
The specified voltage must match the mains voltage. Ob-
serve the type plate.
!
Material losses
The cable entries at the back of the appliance are closed
with cable grommets. To prevent an ingress of water, cut
as small a hole as possible in the cable grommet.
5.8.1 General information
The electrical data is given in the chapter "Specification/Data
table". You will need a BUS cable typeJ-Y(St)2x2x0.8mm². The
BUS cable should not be longer than 50m.
5.8.2 Control panel
2.
3.
1.
1.
D0000062335
1
1 Control panel fastening screws
 Undo the fixing screws of the control panel cover.
Note
A serrated washer is used on one of the fastening screws
to earth the control panel cover.
When you refit the control panel cover after working at
the control panel, place the serrated washer behind the
fastening screw.
The control panel cover is held by means of a tab above and below
which grip behind the appliance side panel.
 Push the control panel cover upwards and pull out at the
bottom to remove it from the appliance.
5.8.3 Cable routing
 Push all connecting cables and sensor leads through one of
the cable entries, "Entry electrical cables," located in the back
panel of the function module.
5.8.4 Terminals X3: Heat pump (compressor) and electric
emergency/booster heater
N
L3
L2
L1
N
L3
L2
L1
WP 400V
X3
MFG 400V
X3
D0000059860
MFG Electric emergency/booster heater of the multi function assembly
WP Heat pump (compressor)
For optimum function, connect all three stages of the electric
emergency/booster heater.

18 | LWZ304 Trend | LWZ 404 Trend | LWZ 304 Integral www.stiebel-eltron.com
INSTALLATION
Installation
5.8.5 Terminal X4
Note
Install additional contactor relays if more than one exter-
nal heating circuit pump is to be connected at the "Pump
heating circuit 2 (HC2)" terminal. Use our relay box (see
chapter "Appliance description/ Further accessories").
N
N
FA
SL
ext. UMV
O/K
L
L
L´
L
L´
L
N
N
L2
L1
EVU
Steuerung
X4
X33
Mischer AUF
Mischer ZU
-
-
-
-
L´
NHK2 230 V
L
D0000059867
EVU Contact for Power-OFF command by the power supply utility
(option)
Steuerung Control unit
Mischer AUF Mixer open
Mischer ZU Mixer close
HK2 Heating circuit 2 pump
O/K Oven / fireplace (option)
ext. UMV External diverter valve
SL Quick-acting air vent valve (option)
FA Window open (option)
The SL terminal is a 230V input for activating ventilation by means
of a pushbutton.
The FA terminal is a 230V output for switching an automatically
controlled window with passive cooling, for example.
5.8.6 Power-OFF
Connect the signal from the power time switch to the X4/power
supply terminal (see chapter "Commissioning/ Power-OFF").
5.8.7 External pumps (PWM)
Note
The power supply to the external pumps is not provid-
ed via the appliance. The X5 terminals only deliver low
voltages.
Externe Pumpen
X5
-
-
GND
GND
CAN-H
+Ub
PWM HK2
PWM SOL
0-10V HK2
0-10V SOL
Td
Td
Tx
Tx
Temperaturen
X5
D0000060873
HK2 Control connection for the pump of heating circuit 2 (control with
PWM signal)
SOL No function
5.8.8 Special tariff
Note
For special tariff connections, ensure that terminal X4/L1
(extractor fan) is always 'live'.
5.8.9 Connecting internal cables/leads
The cylinder temperature sensor and the power cable for the sig-
nal anode are routed out of the function module at the top l.h.
side. All cables/leads are identified accordingly.
1
D0000059866
2
1 Anode connection at the cylinder
2 Earth block X32
 Connect the signal anode at the top of the cylinder. Route
the anode cable through the groove cut into the thermal
insulation.
 Connect the earth cable to earth block X32.

ENGLISH
www.stiebel-eltron.com LWZ 304 Trend | LWZ 404 Trend | LWZ 304 Integral | 19
INSTALLATION
Installation
1
2
D0000039615
1 Sensor well for the cylinder temperature sensor (economy
mode/buffer mode)
2 Sensor well for the cylinder temperature sensor (Comfort)
1
23
D0000039618
1 Aperture in the thermal insulation for the sensor lead
2 Clamp (prevents the cylinder temperature sensor from slip-
ping out)
3 Cylinder temperature sensor inside the sensor well
 Insert the cylinder temperature sensor into the cylinder
sensor well. Ensure that the cylinder temperature sensor is
seated correctly.
The sensors integrated in the appliance, the sensors supplied and
the outside temperature sensor are PTC and PT1000 sensors. The
collector sensor supplied is a PT1000 sensor.
5.8.10 Connecting sensors
Temperaturen
X5
CAN-H
CAN-L
GND
Ts
Ts
Tr
Tr
Tv
Tv
Ta
Ta
+Ub
Externe Pumpen
X5
-
-
GND
GND
PWM HK2
PWM SOL
0-10V HK2
0-10V SOL
Td
Td
Tx
Tx
Temperaturen
X5
D0000060874
Ta Outside temperature sensor
Tv Mixer circuit flow temperature sensor
Tr Room temperature sensor
Ts No function
Tx No function
Td No function
Outside temperature sensor AFS2
26_03_21_0052
The outside temperature sensor should be freely exposed to the
elements. Never fit it above windows, doors, light wells or air
ducts, and never subject it to direct insolation.
Install the outside temperature sensor on a north or north-east
facing wall on the exterior side of a heated room.
Never install the outside temperature sensor near an exhaust air
discharge or any other influencing factors (e.g. drier discharge).
The minimum height above the ground is 2.5m, and minimum
side clearance to windows and doors is 1m.
 Remove the cover of the sensor enclosure.
 Secure the sensor enclosure to the wall using the screw
provided.
 Route the sensor lead through the cable entry in the back
panel of the cylinder module.
 Connect the sensor lead to terminal X5-Ta.
 Connect the sensor lead to the outside temperature sensor.
 Place the cover on the sensor enclosure so that it clicks audi-
bly into place.

20 | LWZ304 Trend | LWZ 404 Trend | LWZ 304 Integral www.stiebel-eltron.com
INSTALLATION
Installation
Room temperature sensor
If planned as part of the system configuration, install the sensor
according to the sensor installation instructions.
 Route the sensor lead through the cable entry in the back
panel of the cylinder module.
 Connect the room temperature sensor to X5-Tr.
5.8.11 Connecting the external programming unit
Note
Check whether the room in which the external program-
ming unit is installed receives a lot of warmth, for ex-
ample sunlight. If it is warmed from outside, the device
might regulate the flow temperature downwards. As a
result, the temperature in other rooms may be lower
than desired.
With an external programming unit, you can switch all appliance
functions and make all settings from the living space. In addition,
the external programming unit captures the room temperature.
If required, this value influences the heating curve. With this, you
can reduce the heating curve if the set room temperature in the
lead room, i.e. the room where the programming unit is installed,
is exceeded (for example through insolation or a wood stove).
The weighting of the room influence is set using the “ROOM INFLU-
ENCE” parameter (“SETTINGS/ HEATING/ HEATING CURVE HC1”).
Temperaturen
X5
CAN-H
CAN-L
GND
Ts
Ts
Tr
Tr
Tv
Tv
Ta
Ta
+Ub
0-10V SOL
D0000071638
GND Ground
CAN-L Low
CAN-H High
+Ub
 Connect the external programming unit with a BUS cable
typeJ-Y(St)2x2x0.8mm²to terminal X5 (GND/CAN-L/CAN-
H/+Ub). The BUS cable should not be longer than 50m.
Note
Observe correct separation when installing the BUS cable,
the mains power cable and the sensor leads.
5.8.12 LWZ 304/404 Trend: Internet Service Gateway
The Internet Service Gateway (ISG) enables you to operate the
appliance within your local home network and via the internet
when on the go.
Temperaturen
X5
CAN-H
CAN-L
GND
Ts
Ts
Tr
Tr
Tv
Tv
Ta
Ta
+Ub
0-10V SOL
D0000071638
GND Ground
CAN-L Low
CAN-H High
The power supply to the ISG is not provided via the appliance.
 Also observe the ISG operating instructions.
The CAN BUS cable conductors are allocated as follows:
White High
Brown Low
Black Earth (Ground)
5.8.13 Safety temperature controller for underfloor heating
system
!
Material losses
In order to prevent excessively high flow temperatures in
the underfloor heating system in the event of a fault, we
always recommend using a safety temperature controller
to limit the system temperature
5.9 Fitting the appliance casing
5.9.1 Installing front panel and cover of the cylinder module
 Hook the front panel of the cylinder module into the hooks
on the cylinder module frame.
D0000039733
1
1 Fixing screw on the cylinder module front panel
 Fix the front panel of the cylinder module to the appliance
using a screw.
 Place the cover onto the cylinder module so that the la-
bels with the terminal designations are located behind the
terminals.
 Secure the cylinder module cover with screws.