STIEBEL ELTRON WPL 10 AC Instruction Manual

OPERATION AND INSTALLATION
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CONTENTS
SPECIAL INFORMATION
OPERATION
1. General information �����������������������������������������3
1.1 Safety instructions����������������������������������������������� 3
1.2 Other symbols in this documentation ����������������������� 4
1.3 Units of measurement ������������������������������������������ 4
1.4 Standardised output data �������������������������������������� 4
2. Safety����������������������������������������������������������4
2.1 Intended use������������������������������������������������������ 4
2.2 Safety instructions����������������������������������������������� 4
3. Appliance description ���������������������������������������5
3.1 Properties ��������������������������������������������������������� 5
3.2 Function ����������������������������������������������������������� 5
4. Settings �������������������������������������������������������5
5. Maintenance and care ���������������������������������������6
6. Troubleshooting ����������������������������������������������6
6.1 Other problems �������������������������������������������������� 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 Accessories�������������������������������������������������������� 7
9. Preparations ��������������������������������������������������7
9.1 Acoustic emissions ���������������������������������������������� 7
9.2 Minimum clearances�������������������������������������������� 7
9.3 Preparation of the installation location ��������������������� 8
9.4 Transport ���������������������������������������������������������� 8
9.5 Siting ��������������������������������������������������������������� 8
9.6 WPM 3 heat pump manager����������������������������������� 9
9.7 Buffer cylinder ��������������������������������������������������� 9
9.8 Preparing the electrical installation ������������������������ 10
10. Installation�������������������������������������������������� 10
10.1 Siting �������������������������������������������������������������� 10
10.2 Heating water connection������������������������������������� 11
10.3 Flow and return connection ���������������������������������� 11
10.4 Oxygen diffusion������������������������������������������������ 11
10.5 Filling the heating system ������������������������������������ 11
10.6 Minimum flow rate ��������������������������������������������� 12
10.7 Setting the flow rate on the heating side ������������������ 12
10.8 Condensate drain ����������������������������������������������� 13
10.9 External heat source 2����������������������������������������� 13
10.10 Safety temperature controller for underfloor heating
system ������������������������������������������������������������ 13
11. Power supply ����������������������������������������������� 14
11.1 Access to the wiring chamber�������������������������������� 14
11.2 Power supply WPL 10 AC (three-phase) ������������������� 14
11.3 Power supply WPL 10 ACS (single phase) ����������������� 16
11.4 Closing the wiring chamber ���������������������������������� 17
12. Commissioning ��������������������������������������������� 18
12.1 Checks before commissioning�������������������������������� 18
12.2 Initial start-up��������������������������������������������������� 20
12.3 Operation and control ����������������������������������������� 20
12.4 Decommissioning����������������������������������������������� 21
13. Maintenance ������������������������������������������������ 21
14. Troubleshooting �������������������������������������������� 21
14.1 Light emitting diodes (LEDs)���������������������������������� 21
14.2 Reset button ����������������������������������������������������� 22
14.3 Resetting the high limit safety cut-out ��������������������� 22
14.4 Fan noise ��������������������������������������������������������� 22
15. Specification ������������������������������������������������ 23
15.1 Connection dimensions and variations��������������������� 23
15.2 Wiring diagram WPL 10 AC (three-phase) ����������������� 24
15.3 Wiring diagram WPL 10 ACS (single phase)��������������� 26
15.4 Output diagrams, heating WPL 10 AC����������������������� 28
15.5 Output diagrams, cooling WPL 10 AC����������������������� 29
15.6 Output diagrams, heating WPL 10 ACS ��������������������� 30
15.7 Output diagrams, cooling WPL 10 ACS ��������������������� 31
15.8 Data table �������������������������������������������������������� 32
GUARANTEE
ENVIRONMENT AND RECYCLING

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SPECIAL INFORMATION | OPERATION
General information
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 resulting 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.
- In dual mode operation, return water from the
second heat generator may flow through the heat
pump. Please note that the return water tempera-
ture may be a maximum of 60 °C.
- 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 system's current condition), and maintenance
by a qualified contractor if required (to return the
system to the desired condition).
- Never interrupt the power supply, even outside
the heating season. The system's active frost pro-
tection is not guaranteed if the power supply is
interrupted.
- If the heat pump and frost protection are com-
pletely switched off, drain the system on the
water side.
OPERATION
1. General information
The chapters "Special Information" and "Operation" are intended
for both the user 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 Safety instructions
1.1.1 Structure of safety instructions
!
KEYWORD Type of risk
Here, possible consequences are listed that may result
from failure to observe the safety instructions.
 Steps to prevent the risk are listed.
1.1.2 Symbols, type of risk
Symbol Type of risk
Injury
Electrocution
1.1.3 Keywords
KEYWORD Meaning
DANGER Failure to observe this information will result in serious
injury or death.
WARNING Failure to observe this information may result in serious
injury or death.
CAUTION Failure to observe this information may result in non-seri-
ous or minor injury.
!

OPERATION
Safety
4| WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
1.2 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.
1.3 Units of measurement
Note
All measurements are given in mm unless stated oth-
erwise.
1.4 Standardised output data
Explanations to determine and interpret the specified standardised
output data
1.4.1 Standard: EN 14511
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.
Further 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
2.1 Intended use
The appliance is designed for the following purposes:
- For central heating
- For central cooling
- For DHW heating
Observe the operating limits listed in chapter "Specification".
This appliance is intended for domestic use. It can be used safely
by untrained persons. The appliance can also be used in a non-do-
mestic environment, e.g. in a small business, as long as it is used
in the same way.
Any other use beyond that described shall be deemed inappropri-
ate. Observation of these instructions and of instructions for any
accessories used is also part of the correct use of this appliance.
Any changes or conversions to the appliance void any warranty.
2.2 Safety instructions
Observe the following safety instructions and regulations.
- The electrical installation and installation of the heating cir-
cuit must only be carried out by a qualified contractor or by
our customer service engineers.
- The qualified contractor is responsible for adherence to
all currently applicable regulations during installation and
commissioning.
- Operate the appliance only when fully installed and with all
safety equipment fitted.
- Protect the appliance from dust and dirt ingress during
building work.
!
WARNING Injury
The appliance may be used by children aged 8 and up and
persons with reduced physical, sensory or mental capa-
bilities or a lack of experience and know-how, provided
that they are supervised or they have been instructed on
how to use the appliance safely and have understood
the resulting risks. Children must never play with the
appliance. Children must never clean the appliance or
perform user maintenance unless they are supervised.
!
WARNING Injury
 For safety reasons, only operate the appliance with
the casing closed.
!

OPERATION
Appliance description
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3. Appliance description
3.1 Properties
The appliance is an air source heat pump for outdoor installation
that is designed to provide central heating. Heat is extracted from
the outdoor air at a low temperature level, and is then transferred
to the heating water at a higher temperature. The heating water
can be heated up to a flow temperature of 60 °C. The refrigerant
circuit is reversed for cooling operation.
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. In such a case in mono energetic operation, the electric
emergency/booster heater is activated as a booster heater.
This appliance has further operational characteristics:
- Suitable for underfloor and radiator heating.
- Preferred for low temperature heating systems.
- Extracts heat from the outdoor air even at outside tempera-
tures of -20 °C.
- Corrosion-protected, external casing made from hot-dipped
galvanised sheet steel plus stove-enamelled finish.
- Comprises all components and safety equipment required for
operation.
- Filled with non-combustible safety refrigerant.
- Suitable for cooling through extraction of heat from the heat-
ing system.
Note
For centralised control over the entire heating system,
you would need the "WPM 3" heat pump manager.
3.2 Function
3.2.1 Heating
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 drawn from the air to the heating system via an additional
heat exchanger (condenser). During this process, the refrigerant
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. Any hoarfrost is au-
tomatically defrosted. Water created from this defrosting process
collects in the defrost pan and is drained off via a hose.
In 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 or heating circuit. When operating without
buffer cylinder, observe the general conditions defined in chap-
ter "Installation / Preparations / Buffer cylinder". Otherwise the
heating water freezes under unfavourable conditions.
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
60 °C.
3.2.2 Cooling
!
Material losses
The heat pump is not suitable for continuous, year-round
cooling.
 Observe the application limits (see chapter "Specifi-
cation / Data table").
Rooms are cooled by reversing the heat pump circuit. Heat is
extracted from the heating water and the evaporator transfers
this heat to the outdoor air.
Area cooling requires the installation of the FEK remote control
unit in a reference room to capture the relative humidity and the
room temperature as part of monitoring the dew point.
3.2.3 Heat pump application limit
The heat pump is switched off if the outside temperature falls
below the selected lower application limit for cooling (parameter
LIMITCOOLING).
4. Settings
The system is operated exclusively with the heat pump manager
(WPM 3).
 Observe the heat pump manager operating and installation
instructions.

OPERATION
Maintenance and care
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5. Maintenance and care
!
Material losses
Maintenance work, such as checking the electrical safety,
must only be carried out by a qualified contractor.
A damp cloth is sufficient for cleaning all plastic and sheet metal
parts. Never use abrasive or corrosive cleaning agents.
1.
2.
1
D0000037831
1 Inspection port
Check the condensate drain monthly (visual inspection). Remove
contaminants and blockages immediately (see chapter "Position-
ing").
!
Material losses
Keep the air discharge and intake apertures free from
snow and leaves.
We recommend an annual inspection (establishing the actual
state) and, if required, maintenance (returning the set state) by a
specialist contractor.
6. Troubleshooting
Fault Cause Remedy
There is no hot
water or the heat-
ing system stays
cold.
No power at the appliance. Check the fuses/MCBs
in your fuse box/
distribution panel.
Replace the fuses/reset
the MCBs if required.
Notify your qualified
contractor if the fuses/
MCBs blow/trip again.
Water is leaking
from the appliance.
The condensate drain may be
blocked.
Clean the condensate
drain as described
in chapter 'Care and
maintenance'.
Condensate is
collecting on the
outside of the ap-
pliance.
The heat pump is drawing heat
from the outdoor air to heat
the building. This can cause the
humidity 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,
expect water to drip from the appliance onto the floor.
6.1 Other problems
If you cannot remedy the fault, notify your qualified contractor.
To facilitate and speed up your enquiry, please provide the serial
number from the type plate. The type plate is located at the front
top, on the right or left hand side of the casing.
Sample type plate
Montageanweisung beachten! Dichtheit geprüft! Made in Germany
*xxxxxxxxxxxxxxxxxx*
1
26�03�01�1570
1 Number on the type plate

INSTALLATION
Safety
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INSTALLATION
7. Safety
7.1 General safety instructions
- Only a qualified contractor should carry out installation,
commissioning, maintenance and repair of the appliance.
- We guarantee trouble-free function and operational reliabil-
ity 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 protects the heating water lines against freezing up.
The integral frost protection circuit starts the circulation pump in
the heat pump circuit automatically at a condenser temperature
of 8 °C, and thereby ensures circulation in all water-carrying sec-
tions. If the temperature inside the buffer cylinder drops, the heat
pump starts automatically no later than when the temperature
falls below +5°C.
8.1 Standard delivery
The following are delivered with the appliance:
- Wiring diagram
- Condensate drain hose
8.2 Accessories
8.2.1 Required accessories
- Heat pump manager with wall mounting casing, WPMW 3
8.2.2 Further accessories
- Wall mounting bracket WK 1
- T-support SK-WPL
- Mounting bracket MK 1
- Cylinder and hydraulic module HSBB 3
- Integral cylinder HSBC 200
- Hydraulic module HM (Trend)
- Pressure hoses DN 25
- Remote control for heating systems FEK
- Remote control for heating systems FE7
- Starting current limiter 25 A
- Safety temperature controller STB-FB
9. Preparations
!
D0000060163
The appliance is designed for siting in front of a wall. Observe the
minimum clearances. If the appliance is installed in an open space
or on a roof, protect the air intake side. Do this by erecting a wall
to shield it against the wind.
9.1 Acoustic emissions
The appliance is louder on the air intake and air discharge sides
than on the two enclosed sides. Please therefore observe the in-
formation below.
For the sound power level, see chapter "Specification/Data table".
 Ensure that the air intake direction is the same as the dom-
inant wind direction. Air should not be drawn in against the
wind.
 Never direct the air intake or discharge towards noise sensi-
tive rooms of the house (e.g. bedrooms).
Lawn areas and shrubs help reduce the spread of noise.
Sound propagation can also be reduced by installing closely
spaced palisade fencing around the appliance. Observe the min-
imum clearances.
9.2 Minimum clearances
≥200
≥2000
≥500
≥1000
≥800
D0000022153

INSTALLATION
Preparations
8| WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
91�00�00�0036
 Never install the appliance in a recess. Two sides of the ap-
pliance must remain exposed.
 Avoid installation on large, echoing floor areas (e.g. tiled
floors).
 Avoid installation between reflective building walls. Reflect-
ing building walls can increase the noise level.
9.3 Preparation of the installation location
The substrate must be horizontal, level, solid and permanent.
 Ensure that the appliance is accessible from all sides.
9.4 Transport
- Lifting straps to transport the appliance can be hooked into
the area highlighted in grey at the bottom of the support
frame.
26�03�01�1548
!
Material losses
Protect the appliance against heavy impact during trans-
port.
If the appliance needs to be tilted during transport only do so
for a short time on one of its longitudinal sides. The longer the
appliance is tilted, the greater the distribution of refrigerant in
the system. Wait approx. 30 minutes before starting the appliance
after it has been tilted.
9.5 Siting
 Observe chapter "Sound emissions".
Note
 Observe the clearance dimension in the following
diagram when using a T-support or wall mounting
bracket.
890
26�03�01�1683�
 Only use weather-resistant cables.
 Protect the flow and return lines against frost with sufficient
thermal insulation. Provide thermal insulation in accordance
with applicable regulations.
 Also protect all supply lines/cables against humidity, damage
and UV radiation by means of a conduit.
Note
When routing the condensate hose, observe chapter "In-
stallation / Condensate drain".
Example: T-support SK-WPL
A
B
2
8
5
7
3
4
6
1
D0000019236
A Depth of frost line
B 300
1 Heating flow
2 Heating return
3 Conduit for supply lines
4 Foundation
5 T-support
6 Gravel bed
7 Drainage pipe
8 Condensate drain
 Observe the static limits of the T-support used.

INSTALLATION
Preparations
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Example: Wall mounting bracket WK 1
≥200
2
5
3 1
4
D0000019244
1 Heating flow
2 Heating return
3 Condensate drain
4 Drainage pipe
5 Wall mounting bracket
 Observe the static limits of the building wall and the wall
mounting bracket.
Example: Mounting bracket MK 1
610
635
265
525
1350
e01
e02
80
110
b01
120
4
5
1
3
2
D0000034844
b01 Entry electrical cables
e01 Heating flow
e02 Heating return
1 Air intake side
2 Air discharge side
3 Main wind direction
4 Condensate drain
5 Supply line outlet
2
8
7
3
4
6
1
2
1
9
5
A
70-80
D0000024451
A Depth of frost line
1 Heating flow
2 Heating return
3 Conduit for supply lines/cables
4 Foundation
5 Mounting bracket
6 Gravel bed
7 Drainage pipe
8 Condensate drain
9 Outlet for supply lines opt.
9.6 WPM 3 heat pump manager
A WPM3 heat pump manager is required to operate the appliance.
This controls the entire heating system.
9.7 Buffer cylinder
A buffer cylinder is recommended to ensure trouble-free appliance
operation.
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.
 When operating without buffer cylinder, observe the details
specified in chapter "Minimum flow rate with individual room
controller by means of FEK / FE7 in the case of systems with-
out buffer cylinder".
!
Material losses
A buffer cylinder with diffusion-proof insulation is essen-
tial for cooling mode.

INSTALLATION
Installation
10 | WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
9.8 Preparing the electrical installation
WARNING Risk of electrocution!
Carry out all electrical connection and installation work
in accordance with national and regional regulations.
WARNING Risk of 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.
!
Material losses
Provide separate fuses for the 3 power circuits (for the
appliance, the electric emergency/booster heater and the
control unit).
 Always connect "L" for the heat pump and the control unit to
the same phase.
Where required, you can install our starting current limiter with
25 A for the WPL 10 AC (see "Additional accessories").
 Route cables with the following cross-sections in accordance
with the respective fuse rating:
MCB/fuse
rating
Assignment Cable cross-section
C 25 A Heat pump
(single phase)
2.5 mm² for routing above the surface
4.0 mm² for routing through a wall
C 16 A Heat pump
(3-phase)
2.5 mm²
B 35 A Electric emergen-
cy/booster heater
(DHC)
(single phase)
6.0 mm² for routing through a wall
4.0 mm² when routing multi-core cables
on a wall or in an electrical conduit on
a wall
B 16 A Electric emergen-
cy/booster heater
(DHC)
(3-phase)
2.5 mm
1.5 mm² with only two live cores and
routing on a wall or in an electrical con-
duit on a wall.
B 16 A Control 1.5 mm²
The electrical data is provided in the chapter "Specification" . You
require a J-Y (St) 2x2x0.8mm² cable as BUS cable.
10. Installation
10.1 Siting
 When installing the appliance, observe the air intake
direction.
 Position the standard appliance on the prepared substrate.
26�03�01�1544
 Remove the cover.
26�03�01�1550

INSTALLATION
Installation
www.stiebel-eltron.com WPL 10 AC | WPL 10 ACS | 11
 Remove the transport locks (threaded rods) from the
compressor.
1
26�03�01�1759
1 Sound insulation
 Position the cover on the appliance.
 Secure the cover with the four screws.
10.2 Heating water connection
The heat pump heating system must be installed by a qualified
contractor in accordance with the water installation drawings that
are part of the technical documents.
 Thoroughly flush the pipework before connecting the heat
pump. Foreign matter, such as welding pearls, rust, sand
or sealant will impair the operational reliability of the heat
pump and can result in the heat pump condenser becoming
blocked.
10.3 Flow and return connection
!
Material losses
Insulate the heating flow and return lines with vapour
diffusion-proof material.
Fit an anti-vibration mount at least 1 m long to the connectors.
Structure-borne noise is largely prevented by the anti-vibration
construction of the heat pump and by the flexible pressure hoses,
which act as anti-vibration mounts.
 Take the position of the heating flow and return from the fol-
lowing figure:
26�03�01�1552
1
2
1 Heating circuit flow
2 Heating circuit return
 Connect the heat pump to the heating circuit. Check for
tightness.
10.4 Oxygen diffusion
!
Material losses
Avoid open heating systems and plastic pipes in under-
floor heating systems 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 heating elements or steel pipes).
!
Material losses
The products of corrosion (e.g. rusty sludge) can settle in
the heating system components and can result in a lower
output or fault shutdowns due to reduced cross-sections.
10.5 Filling the heating system
10.5.1 Water quality
Carry out a fill water analysis before the system is filled. This may,
for example, be requested by the relevant water supply utility.
To avoid damage as a result of scaling, it may be necessary to
soften or desalinate the fill water. Always observe the fill water
limits specified in the "Specification / Data table" chapter.
 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 as for desalination apply.
Note
Suitable appliances for water softening, as well as for
filling and flushing heating systems, can be obtained via
trade suppliers.

INSTALLATION
Installation
12 | WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
10.5.2 Venting the heating system
 Vent the pipework carefully. For this, also activate the air
vent valve integrated into the heating flow inside the heat
pump.
10.6 Minimum flow rate
For heating operation without buffer cylinder, ensure the mini-
mum flow rate and the availability of defrost energy.
10.7 Setting the flow rate on the heating side
Note
In combination with an hydraulic module or integral cyl-
inder, the flow rate can be checked and set at the heat
pump manager. Observe that the flow rate is set indirectly
via the rating of the pump used.
 Check the flow rate in the heat pump manager menu
"INFO / HEATING / FLOW RATE" or "INFO / DHW /
FLOW RATE".
 Set the flow rate in the heat pump manager menu
"COMMISSIONING / HEATING / HEATING CIRC PUMP
RATE" or "COMMISSIONING / DHW / DHW PUMP
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 panel
heating systems.
We recommend the use of a buffer cylinder for installations with
several heating circuits.
The minimum flow rate is set via the temperature differential of
the heating system.
Set the heating circuit pump so that the value is equal to or lower
than the maximum temperature differential.
The setting is made in heat pump mode. For this, make the fol-
lowing settings first:
 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.
10.7.1 Minimum flow rate with individual room controller by
means of FEK / FE7 in systems without buffer cylinder
Maximum temperature differential on the heating side with indi-
vidual room controller and external programming unit:
0
2
4
6
8
10
12
-15 -10 -5 0 5 10 15 20 25 30
D0000063627
1
1 Minimum flow rate
X Outside temperature [°C]
Y Maximum temperature differential [K]
In the case of systems without buffer cylinder, in menu "SET-
TINGS/ HEATING/ STANDARD SETTINGS", set parameter "BUFFER
OPERATION" to "OFF".
In such cases, one or more heating circuits in the heating system
must be left open. Ensure the minimum flow rate (see "Techni-
cal Data / Data table") by means of the correspondingly opened
heating circuits (see table "Design recommendation for underfloor
heating system inside the lead room").
Design recommendation for underfloor heating system inside the lead room:
Minimum flow
rate
Minimum water content of buffer
cylinder or open circuits
Composite pipework 16 x 2mm/
routing gap 10cm
Composite pipework 20 x 2.25mm/
routing gap 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 10 AC 700 19 21 3x70 21 2x70
WPL 10 ACS 700 19 21 3x70 21 2x70
Buffer cylinder always
required
Recommended buffer cylinder
volume, underfloor heating
Recommended buffer cylinder
volume, radiators
enable booster heater
WPL 10 AC no 100 200 Yes
WPL 10 ACS no 100 200 Yes

INSTALLATION
Installation
www.stiebel-eltron.com WPL 10 AC | WPL 10 ACS | 13
 Install the open heating circuit(s) in the lead room (room
where the external programming unit of the heat pump
control unit is installed, such as in the living room). The indi-
vidual room can then be controlled either with the external
programming unit or directly by adjusting the heating curve
or the room influence.
 Fully open the heating circuit(s) in the lead room.
 Close all other heating circuits.
 If an overflow valve has been installed in the heating system,
fully close this overflow valve in order to determine the mini-
mum flow rate.
 Make the settings at the circulation pump when the temper-
ature differential between the flow and return temperature
has stabilised.
 Set the heating circuit pump so that the minimum flow rate
required to operate the system is safeguarded.
 Compare the resulting temperature difference between the
flow and return at the appliance with the diagram "Maximum
temperature differential on the heating side with individual
room controller and external programming unit".
 Set the heating circuit pump so that the maximum tempera-
ture differential is achieved or undershot.
 Set the heating circuit pump to ∆p constant.
 If the appliance will be used for DHW heating, check the set-
ting of the delivery head in DHW mode.
10.7.2 Flow rate with buffer cylinder
When using a buffer cylinder, make the following setting: In the
menu "SETTINGS/ HEATING/ STANDARD SETTINGS", set param-
eter "BUFFER OPERATION" to "ON".
The flow rate can be adjusted using the temperature differential
of the buffer circuit. The value must not fall below the minimum
flow rate.
Maximum temperature differential on the heating side with buffer
cylinder:
1
0
2
4
6
8
10
-15 -10 -5 0 5 10 15 20 25 30
D0000063550
1 Nominal flow rate
X Outside temperature [°C]
Y Maximum temperature differential [K]
 Make the settings at the circulation pump when the temper-
ature differential between the flow and return temperature
has stabilised.
 Compare the resulting temperature difference between the
flow and return at the appliance with the diagram “Maxi-
mum temperature differential on the heating side with buffer
cylinder”.
 Set the buffer charging pump so that the maximum tempera-
ture differential is achieved or undershot.
 If the appliance will be used for DHW heating, check the set-
ting of the delivery head in DHW mode.
 If necessary, adjust the delivery head setting for the DHW
primary pump.
 Set the buffer charging pump and the DHW primary pump to
∆p constant.
10.8 Condensate drain
A condensate drain connector is fitted to the defrost pan at the
factory to enable the condensate to drain off.
26�03�01�1552
1
1 Condensate drain
 Secure a hose to the condensate drain connector.
 Insulate the hose to ensure frost protection.
!
Material losses
Ensure the hose is not kinked. Route the hose with a
slope.
 After routing the hose, check that the condensate can drain
correctly.
10.9 External heat source 2
For dual mode systems, always connect the heat pump into the
return of the second heat generator (e.g. oil boiler).
10.10 Safety temperature controller for underfloor
heating system
!
Material losses
In case of failure, in order to prevent an excessively high
flow temperature in the underfloor heating system, we
generally recommend the use of a safety temperature
controller to limit the system temperature.

INSTALLATION
Power supply
14 | WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
11. Power supply
Note
Observe the operating and installation instructions of the
WPM3 heat pump manager.
The connection must only be carried out by a qualified contractor
and in accordance with these instructions.
Permission to connect the appliance may need to be obtained from
your local power supply utility.
The terminals are located in the wiring chamber of the appliance.
 Observe chapter "Preparing the electrical installation".
 Use appropriate cables in accordance with local regulations
for all connections.
 Route all cables and leads through strain relief fittings.
11.1 Access to the wiring chamber
26�03�01�1544
 Remove the cover.
26�03�01�1552
1
1 Cable entries
 Thread the connecting cables from below through the cable
entries upwards to the connecting chamber.
26�03�01�1535
1
1 Wiring chamber
11.2 Power supply WPL 10 AC (three-phase)
 Connect cables according to the following diagram.
 Connect the electric emergency/booster heater 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 heat pump undershoots the dual mode point, the
electric emergency/booster heater safeguards both the
heating operation and the delivery of high DHW temper-
atures.
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, you can discon-
nect the electric emergency/booster heater if it is not
required for the appliance operation.
Please note that during the heat-up program, the emer-
gency operation cannot be selected.
Pasteurisation
control
The electric emergency/booster heater starts automati-
cally when the pasteurisation control is active in order to
regularly heat the DHW to 60 °C to protect it against the
growth of legionella bacteria.

INSTALLATION
Power supply
www.stiebel-eltron.com WPL 10 AC | WPL 10 ACS | 15
1
2
3
4
5
26�03�01�1730
D0000035392
6
1X5 Electric emergency/booster heater (DHC)
L1, L2, L3, N, PE
Connected
load
Terminal assignment
2.6 kW L1 N PE
3.0 kW L2 N PE
3.2 kW L3 NPE
5.6 kW L1 L2 N PE
5.8 kW L1 L3 NPE
6.2 kW L2 L3 NPE
8.8 kW L1 L2 L3 NPE
2X3 Power supply (heat pump, compressor)
L1, L2, L3, N, PE
3X4 Control voltage
Power supply: L, N, PE
4X2 Low voltage (BUS cable)
BUS High H
BUS Low L
BUS earth
BUS "+" (is not connected)
5 Earth terminal for screening the LV lead
6Ribbon heater
Power supply: L, N, PE
 Earth the LV lead by inverting the screen over the external
sheath and clamping it under the earth terminal.
 Then check the function of the strain relief fittings.

INSTALLATION
Power supply
16 | WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
11.3 Power supply WPL 10 ACS (single phase)
 Connect cables according to the following diagram.
 Connect the electric emergency/booster heater 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 heat pump undershoots the dual mode point, the
electric emergency/booster heater safeguards both the
heating operation and the delivery of high DHW temper-
atures.
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, you can discon-
nect the electric emergency/booster heater if it is not
required for the appliance operation.
Please note that during the heat-up program, the emer-
gency operation cannot be selected.
Pasteurisation
control
The electric emergency/booster heater starts automati-
cally when the pasteurisation control is active in order to
regularly heat the DHW to 60 °C to protect it against the
growth of legionella bacteria.
1
2
3
4
5
26�03�01�1529
D0000035392
6
1X5 Electric emergency/booster heater (DHC)
L, L, N, PE
Connected load Terminal assignment
3.0 kW L N PE
3.2 kW L N PE
6.2 kW L L N PE
2X3 Power supply (heat pump, compressor)
L, N, PE
3X4 Control voltage
Power supply: L, N, PE
4X2 Low voltage (BUS cable)
BUS High H
BUS Low L
BUS earth
BUS "+" (is not connected)
5 Earth terminal for screening the LV lead
6Ribbon heater
Power supply: L, N, PE
 Earth the LV lead by inverting the screen over the external
sheath and clamping it under the earth terminal.
 Then check the function of the strain relief fittings.
!
Material losses
When making the L and N connections of the compressor
and the L and N connections of the control unit in single
phase appliances, ensure that the same phase is used.
Protect the circuit with an RCD.

INSTALLATION
Power supply
www.stiebel-eltron.com WPL 10 AC | WPL 10 ACS | 17
Connection example
BUS H BUS L BUS -
L N PE L L N PE L N PE 1 2 3
WP DHC
K1
L N PE
T
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
N 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 PE
Netz N Netz L Netz L´ Pumpen L UP-WP 1 UP-WP 2 UP-Quelle UP-Hzg. 1 UP-Hzg. 2 UP-WWB UP-Zirkul. 2. WE 2. WE Mischer+ Mischer- UP-Sol/Kue
Außen
Vorlauf
Rücklauf
WB Ein
2. WE
Quelle
Mischer
Analog
Fern 1 Fern 3
BUS H
BUS L
BUS -
BUS +
Fühler 1 Fühler 2
1
3
4
2
D0000035461
1 Heat pump
2 Heat pump manager
3 Main control panel
4 Power-OFF contactor
11.4 Closing the wiring chamber
1
26�03�01�1759
1 Sound insulation
 Position the cover on the appliance.
 Secure the cover with the four screws.
 Connect the circulation pump for the heat utilisation side to
the heat pump manager in accordance with the technical
guides.

INSTALLATION
Commissioning
18 | WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
12. Commissioning
A WPM3 heat pump manager is required to operate the appliance.
All necessary adjustments prior to and during operation are made
on this device.
Only qualified contractors may carry out adjustments on the heat
pump manager commissioning report, commission the appliance
and instruct the owner in its use.
Carry out commissioning in accordance with these installation
instructions and the operating and installation instructions of the
heat pump manager. Our customer support can assist with com-
missioning, which is a chargeable service.
Where this appliance is intended for commercial use, the rules of
the relevant Health & Safety at Work Act must be observed at com-
missioning. For further details, check your local authorising body.
After commissioning, complete the commissioning report that is
included in these instructions.
12.1 Checks before commissioning
Before commissioning, check the following:
12.1.1 Heating system
- Have you filled the heating system to the correct pressure,
and opened the quick-action air vent valve?
12.1.2 Temperature sensor
- Have you correctly positioned and connected the outside
temperature sensor and the return temperature sensor (in
connection with a buffer cylinder)?
12.1.3 Power supply
- Have you correctly connected the power supply?
12.1.4 Transport locks
- Have you removed the threaded rods that secure the
compressor?
12.1.5 Checking the IWS DIP switch settings
Carry out the following steps to make the IWS accessible.
26�03�01�1544
 Remove the cover.
26�03�01�1530
 Remove the bracket highlighted in grey as follows:
1
26�03�01�1531
1 IWS
 Lift the panel highlighted in grey.
26�03�01�1532
1
1 Locking stay
 Secure the panel with the locking stay.

INSTALLATION
Commissioning
www.stiebel-eltron.com WPL 10 AC | WPL 10 ACS | 19
IWS
BA
BA
3
4
1
2
C26�03�01�0921
1 LEDs
2 Reset button
3 DIP switch (WP-Typ)
4 DIP switch (BA)
DIP switch (WP-Typ)
With the DIP switch ("WP-Typ"), you can select the various heat
pump types on the IWS.
Factory setting
Compressor mode with electric emergency/booster heater
WP - Typ
ON
1 2 3 4
D0000057054
 Check whether the DIP switch is set correctly.
Compressor mode with external second heat generator
!
Material losses
In this case, do not connect the electric emergency/boost-
er heater.
If the appliance is operated in dual mode operation with an ex-
ternal second heat generator or as module with a further WPL,
set the DIP switch as follows:
WP - Typ
ON
1 2 3 4
D0000057055
DIP switch (BA)
 Check whether the DIP switch(BA) is set correctly.
Heating mode:
BA
ON
1 2 3 4
D0000057050
Cooling mode:
BA
ON
1 2 3 4
D0000057051
12.1.6 High limit safety cut-out
In ambient temperatures of below -15 °C it is possible that the high
limit safety cut-out of the electrical emergency/booster heater
may trip.
 Check whether the high limit safety cut-out has tripped.
 Remove the cause of the fault.
26�03�01�1528
 Reset the high limit safety cut-out by pressing the reset
button.

INSTALLATION
Commissioning
20 | WPL 10 AC | WPL 10 ACS www.stiebel-eltron.com
12.1.7 Closing the wiring chamber
1
26�03�01�1759
1 Sound insulation
 Position the cover on the appliance.
 Secure the cover with the four screws.
12.2 Initial start-up
12.2.1 Heating curve adjustment
The efficiency of a heat pump decreases as the flow temperature
rises. The heating curve should therefore be adjusted with care.
Heating curves that are set too high cause the zone valves and
thermostatic valves to close, which may lead to the minimum flow
rate required for the heating circuit not being achieved.
 Observe the WPM operating and installation instructions.
The following steps will help you to adjust the heating curve cor-
rectly:
- Fully open thermostatic or zone valves in a lead room (e.g.
living room and bathroom).
We do not recommend installing thermostatic or zone valves
in the lead room. Control the temperature for these rooms
via remote control.
- At different outside temperatures (e.g. –10°C and +10°C),
adjust the heating curve so the required temperature is set in
the lead room.
Standard values to begin with:
Parameters Underfloor heating Radiator heating
system
Heating curve 0.4 0.8
Control response time 5 15
Room temperature 20 °C 20 °C
If the room temperature is not high enough in spring and autumn
(approx. 10 °C outside temperature), raise the "COMFORT TEM-
PERATURE" parameter in the heat pump manager menu under
"SETTINGS / HEATING / HEATING CIRCUIT".
Note
If no remote control is installed, raising the "COMFORT
TEMPERATURE" parameter leads to a parallel offset of
the heating curve.
Increase the "HEATING CURVE" parameter, if the room tempera-
ture is not high enough when outside temperatures are low.
If you raise the "HEATING CURVE" parameter, adjust the zone valve
or thermostatic valve in the lead room to the required temperature
when outside temperatures are high.
!
Material losses
Never reduce the temperature in the entire building by
closing all zone or thermostatic valves, instead use the
setback programs.
When everything has been implemented correctly, the system
can be heated to its maximum operating temperature and vented
once again.
!
Material losses
With underfloor heating systems, observe the maximum
permissible temperature for the system.
12.2.2 Other settings
 For operation with and without buffer cylinder, observe
chapter "Operation / Menu structure / Menu SETTINGS/
STANDARD SETTING/ BUFFER OPERATION" in the operating
and installation instructions of the WPM.
When using the heat-up program
If you use the heat-up program, make the following settings on
the WPM:
 Initially set parameter "DUAL MODE TEMP HZG" to 30°C.
 The set parameter "LOWER APP LIMIT HZG" to 30 °C.
Note
Following the heat-up process, return parameters "DUAL
MODE TEMP HZG" and "LOWER APP LIMIT HZG" to their
default values or to system values.
12.3 Operation and control
!
Material losses
Never interrupt the power supply, even outside the heat-
ing season. The system's active frost protection is not
guaranteed if the power supply is interrupted.
The system does not have to be switched off in summer. The
WPM3 has an automatic summer/winter changeover.