STIEBEL ELTRON WPL 19 A User manual

OPERATION AND INSTALLATION
Air | water heat pump
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» WPL19IK
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» WPL24IK
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2| WPL 19 | WPL 24 www.stiebel-eltron.com
CONTENTS
SPECIAL INFORMATION
OPERATION
1. General information �����������������������������������������3
1.1 Relevant documents_____________________________________________ 3
1.2 Safety instructions_______________________________________________ 3
1.3 Other symbols in this documentation _______________________ 4
1.4 Information on the appliance _________________________________ 4
1.5 Units of measurement __________________________________________ 4
1.6 Standardised output data ______________________________________ 4
2. Safety����������������������������������������������������������4
2.1 Intended use______________________________________________________ 4
2.2 Safety instructions_______________________________________________ 4
2.3 Test symbols ______________________________________________________ 4
3. Appliance description ���������������������������������������5
3.1 Minimum software versions___________________________________ 5
3.2 Properties _________________________________________________________ 5
3.3 Function ___________________________________________________________ 5
4. Settings �������������������������������������������������������5
5. Maintenance and care ���������������������������������������5
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
8.2 Required accessories ___________________________________________ 7
8.3 Additional accessories __________________________________________ 7
9. Information on operating and installation instructions��8
10. WPL19I | WPL24I�������������������������������������������8
10.1 Safety_______________________________________________________________ 8
10.2 Preparations ______________________________________________________ 8
10.3 Installation _______________________________________________________ 12
10.4 Fitting the push-fit connectors_______________________________ 13
10.5 Power supply ____________________________________________________ 17
10.6 Sealing the appliance__________________________________________ 18
10.7 Fitting casing parts_____________________________________________ 19
10.8 Fitting the air hoses____________________________________________ 19
11. WPL19IK | WPL24IK�������������������������������������� 21
11.1 Safety______________________________________________________________ 21
11.2 Preparations _____________________________________________________ 21
11.3 Installation _______________________________________________________ 23
11.4 Power supply ____________________________________________________ 26
11.5 Closing the function module _________________________________ 27
11.6 Sealing the appliance __________________________________________ 28
11.7 Fitting casing parts_____________________________________________ 28
11.8 Connecting the air hoses______________________________________ 28
12. WPL19A | WPL24A ��������������������������������������� 29
12.1 Preparations _____________________________________________________ 29
12.2 Installation _______________________________________________________ 31
12.3 Power supply ____________________________________________________ 35
12.4 Fitting casing parts_____________________________________________ 37
13. Commissioning ��������������������������������������������� 38
13.1 Carrying out checks before commissioning the heat
pump manager__________________________________________________ 38
13.2 Commissioning the heat pump manager __________________38
13.3 Settings ___________________________________________________________ 38
14. Appliance shutdown ��������������������������������������� 39
14.1 Standby mode ___________________________________________________ 39
14.2 Power interruption _____________________________________________ 39
15. Appliance handover���������������������������������������� 39
16. Troubleshooting �������������������������������������������� 39
16.1 Controls on the IWS ____________________________________________ 40
16.2 Light emitting diodes (LEDs)__________________________________ 40
16.3 Resetting the high limit safety cut-out _____________________ 41
16.4 Fan noise _________________________________________________________ 41
17. Maintenance ������������������������������������������������ 41
17.1 Clean condensate pan and drain ____________________________ 41
18. Specification ������������������������������������������������ 43
18.1 Dimensions and connections _________________________________ 43
18.2 Wiring diagram WPL19I | WPL 24I | WPL 19A | WPL
24A________________________________________________________________46
18.3 Wiring diagram WPL19IK | WPL24IK _____________________ 48
18.4 Output diagrams WPL19I | WPL19IK| WPL19A _______ 49
18.5 Output diagrams WPL24I | WPL24IK| WPL24A _______ 50
18.6 Data table ________________________________________________________ 51
GUARANTEE
ENVIRONMENT AND RECYCLING

SPECIAL INFORMATION
General information
www.stiebel-eltron.com WPL 19 | WPL 24 | 3
SPECIAL INFORMATION
- The appliance may be used by children aged8
and older and persons with reduced physical,
sensory or mental capabilities or a lack of ex-
perience and know-how, provided that they are
supervised or they have been instructed on how
to use the appliance safely and have understood
the potential risks. Children must never play with
the appliance. Children must never clean the ap-
pliance or perform user maintenance unless they
are supervised.
- 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.
- Maintain the minimum clearances to ensure trou-
ble-free operation of the appliance and facilitate
maintenance work.
- Maintenance work, such as checking the electri-
cal safety, must only be carried out by a qualified
contractor.
- We recommend an annual inspection (to establish
the current condition of the system), and main-
tenance by a qualified contractor if required (to
return the system to its original condition).
- Following isolation from the mains supply,
parts of the appliance may remain live for up to
20minutes. This is because the capacitors on the
inverter still have to discharge.
- Never interrupt the heat pump power supply,
even outside of the heating season. Otherwise,
system frost protection is not guaranteed.
- The heat pump manager automatically switches
the heat pump to summer or winter mode.
- If the heat pump is completely switched off and
there is a risk of frost, drain the system on the
water side.
OPERATION
1. General information
The chapters "Special information" and "Operation" are intended
for both users and qualified contractors.
The chapter "Installation" is intended for qualified contractors.
Note
Read these instructions carefully before using the appli-
ance and retain them for future reference.
Pass on the instructions to a new user if required.
1.1 Relevant documents
Operating and installation instructions for the WPM heat
pump manager
Operating and installation instructions for system
components
1.2 Safety instructions
1.2.1 Structure of safety instructions
!
KEYWORD Type of risk
Here, possible consequences are listed that may result
from failure to observe the safety instructions.
 Measures to prevent the risk are listed.
1.2.2 Symbols, type of risk
Symbol Type of risk
Injury
Electrocution
1.2.3 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.
!

OPERATION
Safety
4| WPL 19 | WPL 24 www.stiebel-eltron.com
1.3 Other symbols in this documentation
Note
General information is identified by the adjacent symbol.
 Read these texts carefully.
Symbol Meaning
Material losses
(appliance damage, consequential losses and environmen-
tal pollution)
Appliance disposal
 This symbol indicates that you have to do something. The ac-
tion you need to take is described step by step.
1.4 Information on the appliance
Symbol Meaning
Inlet/ intake
Drain/ outlet
Central heating
1.5 Units of measurement
Note
All measurements are given in mm unless stated oth-
erwise.
1.6 Standardised output data
Information on determining and interpreting the specified stand-
ardised output data.
1.6.1 EN 14511
The output data specifically mentioned in texts, diagrams and
technical datasheets has been calculated according to the test
conditions of the standard shown in the heading of this section.
However, there is a deviation from this norm in the output data for
air/water inverter heat pumps at source temperatures of > -7°C
as this concerns partial load values. The associated percentage
weighting in the partial load range can be found in EN14825 and
EHPA quality label regulations.
Generally, the test conditions stated above will not fully match 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 test conditions defined in the first
paragraph 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.
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 test conditions defined in the first paragraph
of this section.
2. Safety
2.1 Intended use
The appliance is designed for central heating within the applica-
tion limits listed in the specification.
The appliance is intended for domestic use. It can be used safely
by untrained persons. The appliance can also be used in non-do-
mestic environments, e.g. in small businesses, as long as it is
used in the same way.
Any other use beyond that described shall be deemed inappro-
priate. Observation of these instructions and of the instructions
for any accessories used is also part of the correct use of this
appliance.
2.2 Safety instructions
Observe the following safety instructions and regulations.
- Only qualified contractors are permitted to carry out electri-
cal work and the installation of the heating circuit.
- The qualified contractor is responsible for adherence
to all applicable regulations during installation and
commissioning.
- The appliance should only be operated once it is fully in-
stalled and all safety equipment has been fitted.
- Protect the appliance from dust and dirt during building
work.
!
WARNING Injury
The appliance may be used by children over 8years of
age and persons with reduced physical, sensory or men-
tal capabilities or a lack of experience and expertise,
provided that they are supervised or they have been
instructed on how to use the appliance safely and have
understood the potential risks. Children must never play
with the appliance. Children must never clean the ap-
pliance or perform user maintenance unless they are
supervised.
!
WARNING Injury
 For safety reasons, only operate the appliance with
the casing closed.
2.3 Test symbols
See type plate on the appliance.
!

OPERATION
Appliance description
www.stiebel-eltron.com WPL 19 | WPL 24 | 5
3. Appliance description
3.1 Minimum software versions
The following minimum software versions are necessary for op-
eration of the heat pump:
- WPM3: 390.10
- FES: 417.04
- IWS: 3 9307A
3.2 Properties
The appliance is an air | water heat pump that oper-
ates as a heating heat pump. The appliance extracts heat
from the outdoor air at a low temperature level and trans-
fers it to the heating water at a higher temperature level.
The heating water can be heated up to a flow temperature of 65°C.
The appliance is suitable for indoor or outdoor installation, de-
pending on the heat pump series.
The appliance is equipped with an electric emergency/booster
heater (DHC). If the dual mode point is undershot in mono mode
operation, the electric emergency/booster heater is activated to
safeguard heating operation and the provision of high DHW tem-
peratures. If the same thing happens in mono energetic operation,
the electric emergency/booster heater is activated as a booster
heater.
Additional features
- Suitable for underfloor and radiator heating systems
- Low temperature heating systems are preferred
- Still extracts heat from the outdoor air at –20°C outside
temperature
- Corrosion-protected, external casing parts made from galva-
nised sheet steel plus stove-enamelled finish
- Comprises all components and safety equipment required for
operation
- Filled with non-combustible safety refrigerant
Note
To control the heating system, you will need the WPM
heat pump manager.
WPL19IK| WPL24IK
The heating circuit pump and a 3-way valve for changeover be-
tween the heating circuit and the DHW circuit are part of the
function module. To heat DHW, the heating water that has been
heated by the heat pump is pumped through an indirect coil in the
DHW cylinder, where it transfers its energy to the DHW.
The function module and heat pump are regulated by an integral,
weather-compensated return temperature controller (WPM heat
pump manager).
3.3 Function
Heat is extracted from the outdoor air via the heat exchanger
(evaporator) on the air side. The refrigerant evaporates and is
compressed by a compressor. This process requires electrical
energy.
The refrigerant is then at a higher temperature level and transfers
the heat extracted from the air to the heating system via an addi-
tional heat exchanger (condenser). The refrigerant then expands
and the cycle begins again.
At air temperatures below approx. 7°C, the humidity in the air
condenses as hoarfrost on the evaporator fins. This hoarfrost is
automatically defrosted. Water created by this defrosting process
collects in the defrost pan and is drained off via a hose.
During the defrost cycle, the fan is switched off and the heat pump
circuit is reversed. The heat required for defrosting is drawn from
the buffer cylinder. The heat pump automatically reverts to heating
mode at the end of the defrost cycle.
!
Material losses
In dual mode operation, return water from the second
heat generator may flow through the heat pump. Please
note that the return temperature must be no higher than
65°C.
4. Settings
The system is controlled exclusively by the WPM heat pump man-
ager.
 Please observe the heat pump manager operating and instal-
lation instructions.
5. Maintenance and care
!
Material losses
Maintenance work, such as checking the electrical safety,
must only be carried out by a qualified contractor.
!
Material losses
 Keep the air discharge and intake apertures free
from snow and leaves.
A damp cloth is sufficient for cleaning all plastic and sheet metal
parts. Never use abrasive or corrosive cleaning agents.
 Protect the appliance from dust and dirt during building
work.
 Every month, check that the condensate drain is working
correctly (visual inspection). When doing so, check for
water collecting below or next to the appliance. See chapter
"Troubleshooting".
We recommend a regular inspection (to establish the current con-
dition of the system), and maintenance by a qualified contractor if
required (to return the system to its original condition).

OPERATION
Troubleshooting
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6. Troubleshooting
Fault Cause Remedy
There is no hot
water or the
heating system
remains cold.
No power at the appli-
ance.
Check the fuses/MCBs in your
distribution board. Replace the
fuses/reset the MCBs if required.
Notify your qualified contractor if
the fuses/MCBs blow/trip again.
Water is leaking
from the appli-
ance.
The condensate drain
may be blocked.
If necessary, contact your quali-
fied contractor.
Indoor installa-
tion:
Condensate is
collecting on the
outside of the
appliance or on
the air hoses.
The drying out phase of
the building is not yet
complete.
This condensate should no
longer form on the appliance
after the house is approx.two
years old, providing the room is
sufficiently well ventilated and
dehumidified.
The relative humidity in
the air is high (≥60%).
A change in weather conditions
should no longer cause conden-
sation to form on the appliance.
The appliance is sited
in a damp room. Damp
rooms are those where
humidity in the air is
high. They may, forex-
ample, be used for drying
laundry.
Ensure that the room is ade-
quately ventilated and dehumid-
ified. If necessary, hang your
laundry in a different room.
Use a vented tumble dryer.
Please note that condenser tum-
ble dryers do not reduce the level
of humidity in the air.
The air hoses are incor-
rectly fitted or poorly
sealed.
Cold air is escaping.
Check that the air hoses are
correctly fitted and sealed. If
necessary, contact your qualified
contractor.
Outdoor installa-
tion: Condensate
is collecting on
the outside of the
appliance.
The heat pump is extract-
ing heat from the outdoor
air to heat the building.
This can cause the hu-
midity in the outdoor air
to accumulate as dew or
frost on the cooled heat
pump casing. This is not
a defect.
Note
Even when the condensate is draining away correctly, it
is not unusual for water to drip from the appliance onto
the floor.
If you cannot remedy the fault, contact your qualified contractor.
To facilitate and speed up your request, provide the number from
the type plate (000000-0000-000000).
Sample type plate
Montageanweisung beachten! Dichtheit geprüft! Made in Germany
*xxxxxxxxxxxxxxxxxx*
26_03_01_1736
1
1 Number on the type plate

INSTALLATION
Safety
www.stiebel-eltron.com WPL 19 | WPL 24 | 7
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.
7.2 Instructions, standards and regulations
Note
Observe all applicable national and regional regulations
and instructions.
8. Appliance description
The appliance provides additional frost protection for the heating
water pipes. The integral frost protection circuit starts the heating
circulation pump in the heat pump circuit automatically at +8°C
condenser temperature, and in doing so ensures circulation in all
water-filled sections.
The heat pump starts automatically when the temperature in the
heat pump circuit drops below +5°C.
8.1 Standard delivery
The casing parts for the appliance are delivered in a separate
packing unit.
8.1.1 WPL19I| WPL24I
- Type plate
Casing parts for indoor installation
- Front panel
- Back panel
- Side casing
- Cover - indoor installation
Connection accessories
- Connecting hoses
8.1.2 WPL19IK| WPL24IK
- Type plate
- Compact function module WPIC3
Casing parts for indoor installation
- Front panel
- Back panel
- Side casing
Connection accessories
- Connecting hoses
8.1.3 WPL19A| WPL24A
- Type plate
Casing parts for outdoor installation
- Front panel
- Back panel
- Side casing
- Cover - outdoor installation
Connection accessories
- Connecting hoses
8.2 Required accessories
8.2.1 WPL19I| WPL24I| WPL19A| WPL24A
- Heat pump manager WPM
8.3 Additional accessories
8.3.1 WPL19I| WPL24I| WPL19IK| WPL24IK
- Air hose LSWP560-4S
- Hose connection panel 560
- Wall outlet AWG 560 H-SR
- Wall outlet AWG 560 H-GL
- Wall outlet AWG 560 V-SR
- Wall outlet AWG 560 V-GL
- Wall outlet AWG 560L
- Wall outlet AWG 600L
- Remote control for FE7 heating systems
- Condensate pump PK 10
- Water softening fitting HZEA
- Internet Service Gateway ISG
- Mixer module MSMW
8.3.2 WPL19A| WPL24A
- Remote control for FE7 heating systems
- Water softening fitting HZEA
- Internet Service Gateway ISG
- Mixer module MSMW
- Duct silencer KSD1
- Ribbon heater HZB-1
- Ribbon heater HZB-2

INSTALLATION
Information on operating and installation instructions
8| WPL 19 | WPL 24 www.stiebel-eltron.com
9. Information on operating and
installation instructions
Note
For clarity, the various heat pumps are covered in sep-
arate chapters. The chapters are named after the heat
pumps to which they refer.
The following chapters apply to all heat pumps.
 Go to the relevant chapter for details of how to in-
stall the relevant heat pump.
10. WPL19I | WPL24I
10.1 Safety
Operation of the appliance in buildings with combustion
equipment
As the appliance can produce negative pressure in the installation
room, we recommend using a tightly sealing door between the
installation room and the living space for operation with com-
bustion equipment.
If, due to its use, the installation room is connected to the ex-
tract 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.
10.2 Preparations
Note
The appliance is designed for indoor installation, except
in damp areas.
10.2.1 Sound emissions
Take the following information into account when selecting the
installation location.
Note
For details regarding the sound power level, see chapter
"Specification / Data table".
- Never install on joists.
 Ensure that the entire appliance frame is in full contact
with the substrate. Uneven substrates can increase sound
emissions.
 Never install the appliance directly below or next to a living
room or bedroom.
 Never direct the air intake and discharge apertures in exter-
nal walls towards neighbouring windows or living rooms/
bedrooms.
 Protect pipe outlets through walls and ceilings with anti-vi-
bration insulation.
10.2.2 Minimum clearances
≥500
≥300
≥500
≥500
≥1000
D0000019242
 Maintain the minimum clearances to ensure trouble-free op-
eration of the appliance and facilitate maintenance work.
10.2.3 Preparing the installation location
 See chapter "Sound emissions".
!
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 humidity levels in the in-
stallation room are high, condensate may form on the
appliance and air hoses. 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 installation room floor.
The room where the appliance is installed must meet the following
conditions:
- Free from the risk of frost
- The room must not be subject to a risk of explosions arising
from dust, gases or vapours.
- If installing the appliance in a plant room together with other
heating equipment, ensure that the operation of other heat-
ing equipment will not be compromised.
- Minimum volume of the installation room. The minimum
volume of the installation room is assured if the minimum
clearances are observed.
- Load bearing floor (for the weight of the appliance, see chap-
ter "Specification/ Data table").
 Ensure that the appliance is accessible from all sides.
 Ensure that the substrate is level, even, solid and permanent.

INSTALLATION
WPL19I | WPL24I
www.stiebel-eltron.com WPL 19 | WPL 24 | 9
 For installation on floating screeds, make provisions for quiet
heat pump operation.
 Isolate the installation surface around the heat pump by
means of a recess. After completing the installation, seal the
recess with a waterproof, sound insulating material, suchas
silicone.
1 2 3 54
26_03_01_1466
1 Concrete base
2 Impact sound insulation
3 Floating screed
4 Floor covering
5 Recess
Note
For details of the dimensions and positions of the air
intake and discharge apertures, as well as the outlets for
hydraulic lines and power cables, see chapter "Specifica-
tion/ Dimensions and connections".
10.2.4 Wall outlet
 To route through the wall, use our wall outlet (see the chap-
ter "Appliance description/ Other accessories").
AWG 560H
Through an exterior wall to the outdoors with a horizontal
wall outlet
510
340
725
290
422
D0000017268
430-465
830-865
D0000022330
AWG 560V
Through an exterior wall to the outdoors with a vertical wall
outlet
510
340
290
422
725
D0000017269
430-465
830-865
D0000022331
AWG 560L
Through a cellar wall into a shaft with a horizontal wall outlet
881
477
878
85
290
510
625
422
824
340
725
D0000017271
430-465
830-865
D0000022330

INSTALLATION
WPL19I | WPL24I
10 | WPL 19 | WPL 24 www.stiebel-eltron.com
AWG 600L
Through a cellar wall into a shaft with a wall outlet
649
647
95
260
400
525
592
646
550
D0000017272
600-635
600-635
D0000022332
Air routing without a duct: Through an outside wall | Through two outside walls around a corner
≥300 ≥300 ≥500
≥1750 ≥1750
≥3000
≥ 1119
≥742
≥2160 ≥2160
D0000019251

INSTALLATION
WPL19I | WPL24I
www.stiebel-eltron.com WPL 19 | WPL 24 | 11
Air routing with a duct: Through an outside wall | Through two outside walls around a corner
≥ 600 ≥ 600
≥ 1000 ≥ 1000
≥300 ≥300 ≥500
≥1750
≥1750
≥3000
≥ 1119
≥742
≥2160 ≥2160
D0000019250
Insulating the brickwork
Ensure that no cold bridges form between the brickwork and the
hose connection panels or wall outlets. Cold bridges can result in
condensation forming in the brickwork.
 If necessary, fit suitable insulation between the brickwork
and the hose connection panels or wall outlets.
10.2.5 Electrical installation
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with national and regional regulations.
WARNING Electrocution
Only use a permanent connection to the power supply.
Ensure the appliance can 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 contactors, circuit breakers, fuses/MCBs,
etc.
Note
The specified voltage must match the mains voltage.
 Observe the type plate.
 For wiring, use cable with the relevant cross-sections. Ob-
serve the applicable national and regional regulations.
MCB/fuse
rating
Assignment Cable cross-section
16 A 2.5 mm²
1.5 mm² for only two live wires and rout-
ing on a wall or in an electrical conduit
on a wall.
3x C 16 A Compressor
(3-phase)
2.5 mm²
3x B 16 A Electric emergen-
cy/booster heater
2.5 mm²
1x B 16 A Control unit 1.5 mm²
The electrical data can be found in the chapter "Specification". The
bus requires a J-Y (St) 2x2x0.8mm² cable.
!
Material losses
Provide separate fuses/MCBs for the three power circuits,
i.e. those of the appliance, the control unit and the elec-
tricemergency/booster heater.
!
Material losses
Provide common fuses/MCBs for the appliance control
cable and the heat pump manager.

INSTALLATION
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Note
The appliance includes an inverter for the variable speed
compressor. In the event of a fault, inverters can cause
DC residual currents. If RCDs are provided, they have to
be type B AC/DC-sensitive.
A DC residual current can block type A RCDs.
 Ensure that the appliance power supply is discon-
nected from the distribution board.
10.2.6 Buffer cylinder
The installation of a buffer cylinder is essential to ensure trou-
ble-free operation of the appliance.
The buffer cylinder provides hydraulic separation of the volume
flows in the heat pump circuit and heating circuit, and also serves
as an energy source for defrosting.
10.3 Installation
10.3.1 Transport
 When transporting the appliance, be aware of its centre of
gravity.
- The centre of gravity is in the area where the compressor is
located.
- Lifting slings for handling the standard appliance can be
hooked in anywhere on the bottom of the frame.
 Protect the appliance against heavy impact during transport.
D0000071298
- If the appliance needs to be tilted during transport, this must
only be for a short time and it must only be titled on one of
its longitudinal sides. When transporting the appliance, en-
sure the compressor is on the upper appliance side.
- The longer the appliance is tilted, the greater the distribution
of refrigerant oil inside the system.
 Wait approximately 30minutes before starting the appliance
after it has been tilted.
10.3.2 Siting
Note
Two screws are available at the top of the appliance frame
to secure the cover.
At the bottom of the frame, one screw is available on each
side to secure the side panels.
 Undo the sixscrews from the appliance frame and keep them
safe.
 Position the standard appliance on the prepared substrate.
 Observe minimum clearances (see chapter "Preparations/
Minimum clearances").
 Place the cover on the appliance and secure with two screws.
10.3.3 Flow and return connection
5
4
3
6
26_03_01_0170
2
1
1 "Heating flow" connection
2 "Heating return" connection
3 Bus cable
4 Control cable
5 Electric emergency/booster heater power cable
6 Appliance power cable
 In the cover, cut out the pipe outlets to precisely fit the "heat-
ing flow" and "heating return" connections. Ensure that the
heat pump seal remains intact and that no splashing water
can enter the machine.
D0000068616
 Guide the assembly connections through the aperture.

INSTALLATION
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D0000068617
 Hook the assembly onto the existing screws.
 Tighten the screws.
D0000068618
 Fit the pressure hoses in the appliance to the "heating circuit
flow" and "heating circuit return" connections.
 Check for leaks.
10.4 Fitting the push-fit connectors
Note
Never install the push-fit connectors in the DHW line.
Only install the push-fit connectors in the heating circuit
and the solar 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.
How the push-fit connectors work
The push-fit connectors are equipped with a retainer with stain-
less steel serrations and an O-ring for sealing. In addition, the
push-fit connectors are equipped with the "twist and lock" func-
tion. 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 main body.
26_03_01_0693
3
1
24
1 Retainer
2 Screw cap
3 Gap between screw cap and main body
4 Main body
26_03_01_0693
Pipe Ø 28 mm
Depth of insertion A 44 mm
!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 by hand against main body as far as it
will go. 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

INSTALLATION
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10.4.1 Heating water connection
!
Material losses
The heating system to which the heat pump is connected
must be installed by a qualified contractor in accordance
with the water installation drawings that are part of the
technical guides.
 Before connecting the heat pump, flush the pipework thor-
oughly with suitable water. Foreign bodies, such as welding
pearls, rust, sand or sealant can impair the operational relia-
bility of the heat pump.
 Connect the heat pump on the heating water side. Check for
tightness.
 Ensure that the heating flow and return are connected
correctly.
 Provide thermal insulation in accordance with applicable
regulations.
 When sizing the heating circuit, observe the internal pressure
differential (see chapter "Specification / Data table").
The pressure hoses acting as anti-vibration insulation for direct
connection of the on-site pipework are integrated inside the ap-
pliance.
10.4.2 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).
 With heating systems that are permeable to oxygen, separate
the heating system between the heating circuit and the buff-
er cylinder.
!
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.
10.4.3 Second heat generator
For dual mode systems, always connect the heat pump into the
return of the second external heat generator, e.g. oil boiler.
10.4.4 Filling the heating system
Carry out a fill water analysis before filling the system. This anal-
ysis may, forexample, be requested by the relevant water supply
utility.
!
Material losses
To avoid damage as a result of scaling, it may be neces-
sary 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 commission-
ing, every time the system is topped up and during
the annual service.
Note
With a conductivity > 1000 μS/cm, desalination treatment
is recommended in order to avoid corrosion.
Note
Suitable appliances for water softening and desalinating,
as well as for filling and flushing heating systems, can be
obtained from trade suppliers.
Note
If you treat the fill water with inhibitors or additives, the
same limits apply as for desalination.
D0000068608
1
1 Drain
 Fill the heating system via the drain.
 After filling the heating system, check the connections for
leaks.

INSTALLATION
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10.4.5 Venting the heating system
 Vent the pipework carefully.
D0000068607
1
1 Air vent valve
 Vent the heat pump via the air vent valve.
10.4.6 Minimum flow rate
You can set the flow rate in heat pump mode. In order to do this,
firstly make the following settings:
 Temporarily remove the fuse from the electric emergency/
booster heater to isolate the emergency/booster heater from
the power supply. Alternatively, switch OFF the second heat
generator.
 Operate the appliance in heating mode.
Minimum flow rate for systems with a buffer cylinder
When using a buffer cylinder, in menu "SETTINGS/ HEATING/
STANDARD SETTINGS", set parameter "BUFFER OPERATION" to
"ON".
In combination with a hydraulic module, cylinder and hydraulic
module or integral cylinder:
 In menu ""COMMISSIONING/ HEATING", set parameter
"HEATING CIRC PUMP RATE" so that the nominal flow rate
required for system operation is assured (see chapter "Speci-
fication/ Data table”).
If the appliance is operated on its own with a WPM:
 Set the heating circuit pump so that the nominal flow rate
required for system operation is assured.
The current flow rate can be viewed in menu "INFO/ HEAT PUMP
INFO/ PROCESS DATA" under "WP WATER FLOW RATE".
Note
The table applies if individual room control is installed.
Sizing recommendation for the underfloor heating system in the lead room:
Minimum flow
rate
Minimum water content of the
buffer cylinder or the open cir-
cuits
Composite pipework 16 x 2mm
/ clearance 10cm
Composite pipework 20 x 2.25mm
/ clearance 15cm
Lead room
floor area
Number of cir-
cuits
Lead room
floor area
Number of cir-
cuits
l/h lm² n x m m² n x m
WPL19I 1000 46 - - - -
WPL24I 1000 57 - - - -
Buffer cylinder always
required
Recommended buffer cylinder
volume, underfloor heating
system
Recommended buffer cylinder
volume, radiators
Activate the integral
emergency/booster
heater
WPL19I yes 100 100 yes
WPL24I yes 100 100 yes

INSTALLATION
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10.4.7 Circulation pump
When configuring the heat pump system, follow the stated max-
imum available external pressure differentials (see the chapter
"Specification/ Data table").
!
Material losses
When adjusting the circulation pump, you must ensure
that the minimum flow rate is guaranteed in all operating
points (see the chapter "Specification/ Data table" in the
heat pump operating and installation instructions).
10.4.8 Condensate drain
A condensate drain hose is fitted to the defrost pan to enable the
condensate to drain off. The condensate drain hose is delivered
inside the refrigeration unit. You can route the condensate drain
hose to the left through the knock-out "condensate drain outlet"
(see chapter "Specification/ Dimensions and connections") or to
the bottom right through the floor plate and out of the appliance.
 Ensure the condensate drain hose is not kinked.
 Ensure the condensate drain hose is not inserted airtight into
a drain. Unhindered drainage requires an ingress of air.
 Route the hose with a continuous fall.
 Use a suitable condensate pump if there is insufficient fall.
Take the building characteristics into account.
 If using a condensate pump, ensure that it delivers at least
6l/min.
Condensate drain towards the left
26_03_01_0956
1
1 Knock-out "condensate drain outlet"
 Use pliers to remove the knock-out "condensate drain outlet"
from the left-hand side panel.
 Route the condensate drain hose to the left and out of the
appliance.
 Route the condensate into a drain.
Condensate drain towards the left
If a bottom drain is provided, you can drain the condensate down-
wards through the "supply line entry" in the bottom of the appli-
ance.
D0000068605
1
1 Knock-out "supply line entry"
 Remove the knock-out "supply line entry" in the bottom of
the appliance.
 Route the condensate drain hose diagonally through the
knock-out aperture "supply line entry".
 Secure the condensate drain hose to ensure it does not slip
out of place.
 Route the condensate into the drain in the floor.
10.4.9 Checking the draining of condensate
After routing the condensate drain hose, check that the condensate
can drain correctly. Proceed as follows:
 Pour water onto the evaporator, which will then flow into the
defrost pan. Observe the maximum condensate drain capac-
ity of 6l/min.
 Check whether the water is draining off through the conden-
sate drain hose.
10.4.10High limit safety cut-out for underfloor heating systems
!
Material losses
In order to prevent excessively high flow temperatures
in the underfloor heating system causing damage in the
event of a fault, we always recommend using a high limit
safety cut-out to limit the system temperature.

INSTALLATION
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10.5 Power supply
WARNING Electrocution
Before working on the appliance, isolate it from the
power supply at the control panel.
The connection must only be made by a qualified contractor and
in accordance with these instructions.
You must have permission to connect the appliance from the rel-
evant power supply utility.
Note
Please observe the heat pump manager operating and
installation instructions.
The terminals are located in the appliance control panel.
 See chapter "Preparations/ Electrical installation".
 Use appropriate electrical cables in accordance with local
regulations.
 Check that the strain relief fittings are working as intended.
 Connect the heating circulation pump to the heat pump man-
ager in accordance with the technical guides.
10.5.1 Connecting electrical cables
Note
In the appliance there are cable clamps that you can use
for routing the electric cables.
D0000071291
 Route the electric cables as shown in the illustration.
10.5.2 Heat pump connection
Terminal assignment
 Connect the cables in line with the following diagrams.
 Then check that the strain relief fittings are working as
intended.
 Put the sheath on the earth clip.
D0000059492
1
1 Earth clip
X2 Low voltage (bus)
H Bus high
L BUS Low
Bus earth
" + " bus " + "
X3 Heat pump power supply (WP)
L1, L2, L3, N, PE
X4 Control unit ("Steuerung")
ON Compressor output signal
ERR Output signal fault
L, N, PE Power supply
X5 Electric emergency/booster heater power supply
(DHC)
L1, L2, L3, N, PE
X7 Connection for ribbon heater
L, N, PE
Note
As soon as the compressor is running, the "ON" output
issues a 230V signal.
Note
The "ERR" output issues a 230V signal for every appliance
fault. The output passes the signal on to the external
controller.
In the case of temporary faults, the output switches the
signal through for a specific time.
In the case of faults that result in a permanent appliance
shutdown, the output switches through permanently.

INSTALLATION
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10.5.3 Emergency/booster heater power supply
Terminal X5: Appliance and electric emergency/booster heater
(DHC)
 Connect the electric emergency/booster heater to terminal X5
if you want to utilise the following appliance functions:
Appliance func-
tion
Effect of the electric emergency/booster
heater
Mono energetic op-
eration
If the dual mode point is undershot, the electric emer-
gency/booster heater safeguards both the heating oper-
ation and the provision of high DHW temperatures.
Emergency mode Should the heat pump suffer a fault that prevents its
continued operation, the heating output will be covered
by the electric emergency/booster heater.
Heat-up program
(only for underfloor
heating systems)
Where return temperatures are < 25°C, the electric
emergency/booster heater must provide the necessary
heat for screed drying.
With these low system temperatures, the drying heat
must not be provided by the heat pump, otherwise the
frost protection of the appliance can no longer be guar-
anteed during the defrost cycle.
When the heat-up program has ended, the electric
emergency/booster heater can be disconnected if it is
not required for the appliance operation.
Please note that during the heat-up program, emergen-
cy mode is not available.
Pasteurisation con-
trol
The electric emergency/booster heater starts automat-
ically when pasteurisation control is active, in order to
regularly heat the DHW to 60°C to protect it against the
growth of legionella bacteria.
10.5.4 Internet Service Gateway ISG
The Internet Service Gateway ISG enables you to operate the heat
pump in your local home network and via the internet whilst you
are away from home. Connect the Internet Service Gateway to
terminals H, L, and to terminal strip X2 of the appliance.
The ISG is not supplied with power by the heat pump.
 Also observe the ISG operating instructions.
10.6 Sealing the appliance
Note
If you want to prevent negative pressure in the instal-
lation room, you can seal the appliance by affixing the
plastic screen provided.
D0000068609
 Apply fabric tape to seal the hole at the bottom of the frame
on the left-hand side. The fabric tape is supplied with the air
hose.
D0000068610D0000068611
 Hang the plastic screen with the pre-cut holes onto the hooks
on the appliance.

INSTALLATION
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D0000068612
 Remove the backing from the adhesive strips on the frame
and on the plastic screen.
 Secure the plastic screen by pressing it onto the standard
appliance.
 Seal the gaps around the hooks with fabric tape.
10.7 Fitting casing parts
2
13
1
54
26_03_01_1443
1 Side panel
2 Cover
3 Front panel
4 Type plate
5 Back panel
 Hook the side panels, front panel and back panel into the
hooks on the standard appliance. Secure the casing parts
with one screw each.
 Affix the type plate supplied in a highly visible position on
one of the appliance casing panels.
10.8 Fitting the air hoses
Note
In the case of heat pumps installed indoors, if a blow-
er door test to EN13829 is to be carried out, then all
apertures which are purposely provided in the building
envelope must be closed or sealed off before the air hoses
are installed.
 For the blower door test, seal off the heat pump
supply air and extract air ducts.
Note
Air hoses guide the intake air to the appliance and route
the discharge air from the appliance outdoors. They are
highly flexible, thermally insulated and self-extinguishing
in case of fire.
Note
If the air hoses are shortened, the sound power level at
the air inlet/ outlet rises.
The air hose can be extended by turning the hose spirals into
each other. There must be an overlap of approx.30cm. The total
length of hoses on the air intake and discharge sides must not
exceed 8m.
 Never incorporate more than four 90° bends. The radius of
the bends must be at least 600mm, relative to the centre of
the hose.
 Cut to size using a sharp knife. The wire spirals can be cut
using wire cutters.
 Secure the air hose at intervals of approx. every1m to pre-
vent it from sagging.
 Manipulate the ends of the air hoses to fit the oval shape of
the connectors on the cover and the hose connection panels
or wall outlets.
D0000070816
 Firstly, push the outer hose slightly upwards.

INSTALLATION
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D0000070817
 Push the inner hose halfway down the connector.
D0000070818
 Seal the inner hose by affixing it to the connector using the
fabric tape provided.
D0000070819
 With the sound-optimised hoses (LSWP560-4S), pull the
sheet over the connector.
D0000070820
 With the sound-optimised hoses (LSWP560-4S), seal the
sheet to the connector using the fabric tape provided.
D0000070821
 Place the sealing strip provided around the connector.
D0000070822
 Pull the outer hose over the connector.
D0000070824
 Secure the hose using the oval hose clip provided and seal it.