STIEBEL ELTRON wpf 20 Specification sheet

OPERATION AND INSTALLATION
BRINE/WATER HEAT PUMPS
»WPF20
»WPF27
»WPF40
»WPF52
»WPF66

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General instructions
The chapter Operation is intended for the equipment user and the
heating contractor.
The chapter Installation is intended for the heating contractor.
The heat pump installation also requires the WPM II heat pump
manager operating instructions.
Subject to the relevant system, also observe the operating and
installation instructions of the components that are part of the
system.
Please read carefully!
Read these instructions carefully before using the unit
and retain them for future reference. If the device
is passed on to a third party please hand these
instructions to the new user.
Key
Symbols in these installation instructions:
In this documentation you will come across symbols and highlights
that are defined as follows:
!Danger to life through electrocution!
!Risk of damage!
Information regarding potential situations that bring
a risk with them that might occur during the device
installation or operation, the consequences of which
may be equipment damage, environmental pollution
or material loss.
» The "»" symbol indicates that you have to do something. The
action you need to take is described step by step.
General instructions__________________________________________________2
Key ___________________________________________________________________________ 2
OPERATION _____________________________________________ 2
1 Safety ____________________________________________________________3
1.1 Correct use___________________________________________________________ 3
1.2 Safety instructions _________________________________________________ 3
1.3 CE designation ______________________________________________________ 3
2 Device description ______________________________________________3
2.1 Operational characteristics _______________________________________ 3
2.2 Function ______________________________________________________________ 3
3 Control __________________________________________________________3
4 Maintenance and care__________________________________________3
5 What to do if... _________________________________________________3
INSTALLATION __________________________________________ 4
6 Safety ____________________________________________________________4
6.1 Instructions, standards and regulations, CE __________________ 4
7 Device description ______________________________________________5
7.1 Standard delivery___________________________________________________ 6
7.2 Accessories __________________________________________________________ 6
8 Installation ______________________________________________________6
8.1 Transport_____________________________________________________________ 6
8.2 Positioning___________________________________________________________ 6
8.3 Installation of the heat pump system __________________________ 9
8.4 Installation of the heat consumer system ____________________ 10
8.5 Fitting the casing parts___________________________________________ 12
8.6 Removing the casing parts ______________________________________ 13
8.7 Power supply _______________________________________________________ 14
8.8 Modules _____________________________________________________________ 14
9 Commissioning________________________________________________ 16
9.1 Operation and control ___________________________________________ 16
10 Maintenance___________________________________________________ 16
11 Troubleshooting_______________________________________________ 17
12 Specification___________________________________________________ 19
12.1 Standard control___________________________________________________ 19
12.2 Wiring diagrams___________________________________________________ 20
12.4 Output diagrams ____________________________________________ 24
13 Commissioning report________________________________________ 29
GUARANTEE____________________________________________ 35
ENVIRONMENT AND RECYCLING______________________ 35
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CONTENT | CONTROL
GENERAL INSTRUCTIONS | KEY

1 Safety
1.1 Correct use
This device is exclusively designed for heating water heating. Any
other or additional use is inappropriate, in particular the heating
of alternative media. The correct use also includes the observation
of the operating and installation instructions. Only use the device
for the purpose stated by the manufacturer and never change or
convert the device in any way!
1.2 Safety instructions
Observe the following safety information and instructions.
The electrical installation and installation of the refrigerant circuit
must only be carried out by a recognised, qualified contractor or
by qualified Stiebel Eltron customer service engineers.
The recognised contractor is responsible for adherence to
all currently applicable instructions during installation and
commissioning.
Operate this device only if it is fully installed and all safety
equipment is fitted.
!Danger to life through electrocution!
Never spray the device with water or other liquids.
!Risk of damage!
Prior to maintenance work, isolate the device from its
power supply.
Where children or persons with limited physical, sensory or mental
capabilities are to be allowed to control this equipment ensure
that this will only happen under supervision or after appropriate
instructions by a person responsible for their safety. Children
should be supervised to ensure that they do not play with the
equipment.
1.3 CE designation
The CE designation shows that the device meets all the essential
requirements:
— Electrical Compatibility Directive (2004/108/EC)
— Low Voltage Directive (2006/95/EC)
— Pressure Equipment Directive (97/23/EC)
The rating plate is located at the back of the heat pump.
2 Device description
2.1 Operational characteristics
The WPF is a heating heat pump designed as brine/water heat
pump. The heat pump extracts energy from the heat source
medium, i.e. brine, at a low temperature level. This extracted
energy is then transferred to the heating water at a higher
level, enriched with the energy drawn by the compressor.
Subject to the heat source temperature, the heating water can be
heated up to a flow temperature of 60 °C.
A modular operation is possible with the WPF.
2.2 Function
The heat source medium (brine) enters the heat pump evaporator.
There, heat is extracted from the medium, so it exits the heat
pump at a lower temperature.
The energy made useful through the heat pump is transferred to
the heating water inside the condenser.
Then, the heating water transfers its energy to the heating
circuit.
3 Control
The heat pump is exclusively controlled by the heat pump manager
WPM II. Therefore, observe the instructions in the chapter Operation
in the operating and installation instructions of the heat pump
manager WPM II.
4 Maintenance and care
!Risk of damage!
Maintenance work, such as checking the electrical
safety, must only be carried out by a qualified
electrician. Protect the equipment from dust and dirt
ingress during building work.
A damp cloth is sufficient for cleaning all plastic and sheet steel
parts. Do not use abrasive or corrosive cleaning agents!
!Risk of damage!
Check the refrigerant circuit of the heat pump annually
for tightness in accordance with EU Directive 842/2006.
5 What to do if...
. . . there is no hot water or the heating system remains cold:
Check the fuse/circuit breaker in your fuse box. If it has blown/
tripped, replace/reset the fuse/MCB. Notify your local contractor
if the fuse/MCB blows/trips again.
Notify your local contractor in case of all other faults.
OPERATION
SAFETY | DEVICE DESCRIPTION | CONTROL | MAINTENANCE AND CARE
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6 Safety
6.1 Instructions, standards and regulations, CE
On the water side:
DIN EN12828: Safety equipment for hot water heating systems
TRD 721: Safety equipment to prevent excess pressure – safety
valves.
On the electrical side:
DIN VDE 0100: Regulations for the installation of HV systems with
rated voltages up to 1000 V.
VDE 0701: Regulations regarding the repair, modification and
testing of used electrical equipment.
DIN-EN 60335 part 2-40
TAB: Technical connection conditions for connection to the
LV mains.
On the refrigerant side:
EN 378: Safety and environmental requirements.
DIN 7003 (draft version)
General:
Collation of technical requirements for boiler rooms, e.g. Boiler
Room Directives or national/local Building Regulations, commercial
and fire as well as emission control regulations and requirements,
or local regulations.
TA-Lärm: Techn. noise protection regulations [Germany].
EnEV: Energy Savings Order [Germany]
The CE designation shows that the device meets all the essential
requirements: The rating plate is located at the back of the heat
pump.
INSTALLATION
SAFETY
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7 Device description
A Equipment layout
1
2
4
10
8
14
7
5
93
12
C26_03_01_1318
13
11
10
1
5
4
10
8
6
7
2
93
15
13
11
10
C26_03_01_0797
14
WPF 40, 52, 66
WPF 20, 27
15
12
1 Condenser
2 Evaporator
3 Sight glass
4 High pressure limiter
5 Low pressure sensor
6 Motor protection switch (only for WPF 52 and 66)
7 Filter dryer
8 Expansion valve
9 Compressor
10 Fill & drain valve (heating)
11 Fill & drain valve (brine)
12 Phase monitoring relay
13 Electrical terminals
14 Starting current limiter
15 High pressure sensor
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INSTALLATION
EQUIPMENT LAYOUT

7.1 Standard delivery
Heat pumps are delivered in two shipping units.
Designation Part no.
Standard heat pump device
Casing parts 223384
7.2 Accessories
Designation Part no.
Heat pump manager with wall mounting enclosure, WPMW II 185450
Heat pump manager as control panel mounted version, WPMS II 185451
Mixer module with wall mounting enclosure, MSMW 074012
Mixer module as control panel mounted version, MSMS 074011
Cylinder SBP 700 E 185459
Cylinder SBP 700 E SOL 185460
Kit WPVB 227760
Heating system remote control FE 7 185579
Contact sensor AVF 6 165341
Immersion sensor TF 6 165342
Heat transfer medium (concentrate) (30 litre can) 161696
8 Installation
8.1 Transport
To protect the equipment against damage, transport it vertically
inside its packaging. Storage and transport at temperatures below
– 20 °C and in excess of + 50 °C are not permissible.
In the top of the frame are four holes for fitting lifting eyes M 12
where the equipment can be lifted.
The casing parts are delivered in a separate package, and these
are fitted to the device at the place of installation.
8.2 Positioning
8.2.1 General
Level the device horizontally by adjusting the equipment feet.
To prevent the heat pump from being damaged by frost in case of
external installation, fit and electrically connect the contact sensor
AVF 6 (part no.: 165341) into the heating return as frost protection.
Electrical connection and sensor installation, see chapter 9.
Maintain the following minimum clearances to adjacent
surfaces:
— to the sides 300 mm
— in front 1500 mm
— upwards 100 mm
— The clearance to the back is subject to the installation and
installation location.
8.2.2 External installation
We recommend foundations as base for the device
(see Fig. D) .
Route all supply lines inside a conduit that is free from frost
(protective pipe).
Protect the connection area at the back panel against all weather
and solar influences.
8.2.3 Internal installation
The room where the WPF is to be installed must meet the following
conditions:
—Load-bearing floor. For the weight of the WPF, see
"Specification".
— For a quiet heat pump operation on floating screeds, recess the
screed and the anti-vibration insulation around the installation
location
(see Fig. C) of the heat pump.
— The room must not be subject to a risk of explosions arising
from dust, gases or vapours. Never allow the floor area and the
volume of the installation room to be less than the minimum
values listed in the table.
Type Volume Floor area
WPF 20 14 m³ 5 m²
WPF 27 16 m³ 7 m²
WPF 40 23 m³ 9 m²
WPF 52 28 m³ 11 m²
WPF 66 33 m³ 13 m²
— When installing the WPF in a boiler room together with other
heating equipment ensure, that the operation of other heating
equipment will not be impaired.
8.2.4 Sound emission.
Never install the heat pump immediately below or adjacent to
bedrooms. Insulate pipes through walls and ceilings against
structure-borne noise transmission.
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INSTALLATION
INSTALLATION

B Dimensions
C26_03_01_0867
4
2
1
C Plinth for internal installation
C26_03_01_0802
3
1 Concrete ceiling
2 Impact sound insulation
3 Floating screed
4 Recess
D Foundation for external installation
C26_03_01_0803
INSTALLATION
INSTALLATION
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E Water and brine connection
C26_03_01_0866
2
1
3
4
1 Heating flow
2 Heating return
3 Brine flow
4 Brine return
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INSTALLATION
INSTALLATION

8.3 Installation of the heat pump system
Design the heat source system for the brine/water heat pump in
accordance with Stiebel Eltron technical guides.
Permitted brine:
— Ethylene glycol
— Propylene glycol
— Heat transfer medium as concentrate part no.: 161696
— Heat transfer medium as ready-mixed solution part no.:
185472
When using the heat transfer medium with part no.: 185472, never
seal the heat source system with hemp.
8.3.1 Circulation pump and required flow rate
Use a circulation pump with compound-filled windings to supply
the brine, to prevent an earth short circuit through condensation
in the electrical part of the pump (cold water version).
Size the circulation pump in accordance with the system-specific
conditions, i.e. nominal flow rate and pressure drop must be taken
into consideration (see "Specification").
An adequate flow rate must be safeguarded at every possible
brine temperature, i.e.:
Size the nominal flow rate at brine temperature 0 °C with a
tolerance of + 10 %.
8.3.2 Connection and filling with brine
Prior to connecting the heat pump, check the heat source circuit
for possible leaks, and flush thoroughly.
Calculate the volume of the heat source circuit. You can obtain
the brine volume inside the heat pump from the "Specification"
table.
The overall volume equals that of the required amount of brine
that should be mixed
from 33 % by vol. undiluted ethylene glycol
and 67 % by vol. water.
Mix 1 unit of undiluted ethylene glycol with 2 units of water
(max. chloride content of the water 300 ppm) and then fill into
the system.
Check the brine concentration:
Determine the density of the ethylene glycol water mixture (e.g.
with an hydrometer). Using the density and temperature, the
current level of concentration can be checked in the diagram
(see
Fig. F)
.
F Density Uof ethylene glycol water mixtures of various
concentrations
C26_03_01_0833
{= Frost protection
!Risk of damage!
The quoted output details refer to ethylene glycol.
These output details vary slightly when using
propylene glycol.
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INSTALLATION
INSTALLATION
1.130
1.120
1.110
1.100
1.090
1.080
1.070
1.060
1.050
1.040
1.030
1.020
1.000
0.990
0.980
1.010

8.3.3 Checking the flow rate (during heat pump commissioning)
Check the flow and return temperatures of the heat source. For
this, determine the temperature differential by measuring the
temperature under the thermal insulation on both flow and
return pipes of the heat pump. The diagram (Fig. G) shows the
temperature spread at the nominal flow rate.
!Risk of damage!
At the WPM II, set parameter 12 (source) in the
commissioning list to "Ethylene glycol", otherwise the
frost stat would stop the heat pump at temperatures
below 7 °C. The source inlet temperature can be
checked on the display of the WPM II under the Info
Temp. system parameter.
G Temperature spread at nominal flow rate
C26_03_01_0834
A Brine = heating flow 35 °C
B Brine = heating flow 50 °C
T1 Temperature differential
T2 Source inlet temperature
8.4 Installation of the heat consumer system
8.4.1 Implement the heat consumer system (heating circuit)
in accordance with current technical rules. For safety equipment
in heating systems, consult the DIN EN 12828.
Protect the heating water lines against frost and moisture (only
in case of external installation). Protect flow and return lines
in external installations with an adequate amount of thermal
insulation against frost and by routing them inside a conduit
against moisture
(see Fig. D).
Maintain the required insulation thickness in accordance with the
Heating System Order [or local regulations].
The integral frost protection control (inside the heat pump), that
automatically starts the circulation pump in the heat pump circuit
at + 8 °C and thereby safeguards circulation in all water-bearing
components, offers additional frost protection. The heat pump is
started automatically no later than when the temperature inside
the buffer cylinder drops below + 5 °C.
Prior to connecting the heat pump, check the heating system for
leaks, flush it thoroughly, fill and carefully vent it.
When filling the system with heating water, observe VDI 2035,
sheet 1 [or local regulations]. In particular, this means that
— during the service life of the system, the total of the fill and
top-up water must not exceed three times the nominal volume
of the heating system,
— the total alkaline earths in the water must be < 3.0 mol/m³,
— the total water hardness must be < 3 mmol/l. Soften the water,
if the above conditions are not met.
Generally soften the heating water, if the specific system volume
> 20 l/kW output (e.g. systems with buffer cylinder).
Ensure the correct connection of the heating flow and return.
Fit the thermal insulation in accordance with local regulations
appertaining heating systems.
8.4.2 Buffer cylinder
A buffer cylinder is recommended to ensure a trouble-free heat
pump operation. The buffer cylinder provides hydraulic separation
of the volume flow in the heat pump circuit and the heating circuit.
The flow rate in the heat pump remains constant if, for example,
the flow rate in the heating circuit is reduced by thermostatic
valves.
8.4.3 Circulation pump (cylinder primary pump)
When using a buffer cylinder, observe the pressure drop of the
evaporator, of the connecting lines, bends, valves etc. in sizing the
circulation pump to be installed.
8.4.3 Circulation pump (heating circuit pump)
Where no buffer cylinder is used, size the circulation pump on the
heating side taking the condenser pressure drop into consideration.
The flow rate at 'T = 10 K (see "Specification") of the heat pump
must be assured under all operating conditions of the heating
system through the installation of an overflow valve.
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INSTALLATION
INSTALLATION

8.4.5 Second external heat source
For dual-mode heating systems, always connect the heat pump
into the return of the second heat source (e.g. oil fired boiler).
High heating water temperature: In dual-mode heating systems,
the return water from the second heat source can flow through
the heat pump, immediately after it has been switched off, with
a max. temperature of 60 °C. The temperature may be 70 °C no
earlier than ten minutes after the heat pump has been shut down.
8.4.6 Heat meter
Observe the additional pressure drop when installing heat meters
on the heating side. The sieves inside the heat meters are easily
blocked by dirt particles in the heating circuit, further increasing
the pressure drop.
8.4.7 Oxygen diffusion
Steel radiators, pipes or steel containers can corrode through
oxygen diffusion if permeable plastic pipes are used in underfloor
or open heating systems.
The product of corrosion, i.e. rusty sludge, can settle inside the
heat pump evaporator and can result in output loss through a
reduction of cross-section or in a heat pump shutdown triggered
by the high pressure limiter.
Therefore it is advisable to avoid open heating systems or the
installation of steel pipes in conjunction with plastic pipes that are
permeable to oxygen in underfloor heating systems.
8.4.8 Scaling
Water quality, operating conditions and the water volume are
decisive factors for the extent of scaling. To prevent damage to
valves, heat exchanger and heating elements, check the water
condition and assess it in accordance with VDI 2035 [or local
regulations].
Note: An awareness of the hardness in accordance with the
Detergent Act [Germany] is insufficient. Decisive for scaling is the
concentration of calcium hydrogen carbonate; relevant detailscan
be supplied by your water supply utility.
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INSTALLATION
INSTALLATION

8.5 Fitting the casing parts
H Fitting the plinth facia and control panel frame
1
2
1
C26_03_01_0791
2
1.
3.2.
» Hook the plinth facia 1into the device frame and secure each with three screws
» Position the covers 2and secure each with two screws to the sides.
I Fitting the side covers
C26_03_01_0792
2
1
» Fix the guard plate 1with four screws. The both in the front with the toothed locked washer.
» Secure the control panel frame 2with five screws.
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INSTALLATION
INSTALLATION

1
J Fitting the side panels
C26_03_01_0793
1
2
» Hook the side panels 1from the top into the slots and hooks
provided and secure with one screw each at the bottom of the
control panel frame.
» Install sound insulation 2in the control panel frame
K Fit front panel
C26_03_01_0795
» Hook the bottom of the front panel into the control panel frame,
pivot it towards the frame and secure with one screw on each
side.
L Fit centre cover
C26_03_01_0794
» Position the cover at the front of the device and push it back;
then secure it with two screws.
» Make the power supply before the centre cover and front panel
are fitted.
»
8.6 Removing the casing parts
The casing parts are removed in reverse order.
INSTALLATION
INSTALLATION
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8.7 Power supply
Notify your local power supply utility of the electrical connection.
Only qualified electricians must carry out the installation in
accordance with these instructions.
!Danger to life through electrocution!
Before any work, isolate the equipment from the power
supply at the control panel.
Observe VDE 0100 [or local regulations] and the regulations of your
local power supply utility.
The heat pump must be able to be separated from the mains power
supply by an additional isolator, that disconnects all poles with at
least 3 mm contact separation. For this purpose, use contactors,
main isolators, fuses, etc. on site.
The terminals are located above the control panel. Remove the lid
to enable the equipment to be connected
(see Fig. K) .
The following are connected at the terminals:
— the power supply of the IWS heat pump control unit
— the compressor power supply
— the brine pump power supply
— the BUS cable (J-Y (St) 2x2x0.8)
Ensure that High, Low and Ground are correctly connected.
— the enable signal for the stand-alone operation at terminal X4/2.
For this, remove the jumper between X4/L and X4/2.
The IWS (integral heat pump controller) is a PCB that is fitted as
standard into the heat pump control panel. The IWS controls the
contactors of the compressors and the starting current limiter,
receives the signal inputs for high pressure, low pressure and
central faults and contains the BUS interface to the WPM II.
Use appropriate cables in accordance with local regulations
for all connections. For this, observe the Electrical details in
"Specification" and the Electrical connection diagram.
Check the strain relief function.
Observe the operating instructions for the WPM II heat pump
manager.
Connect the circulation pump for the heat consumers in accordance
with the electrical connection diagram
or the engineering
documentation.
In case of external installation, use only weather-proof
connecting cables to VDE 0100 [or local regulations]. As a
minimum requirement, use cables with rubber sheathing with
the identification 60245 IEC 57. Route all lines inside a conduit
(protective pipe).
To prevent the heat pump from being damaged by frost in case of
external installation or when installing it in a room that is not free
from the risk of frost, fit and electrically connect the contact sensor
AVF 6 (part no.: 165341) at the heating-return. The contact sensor
is electrically connected at terminals X2/4 and X2/5.
The heating circuit pumps are started when the heating-return
temperature falls to +8 °C. The reverse switching hysteresis is
4 K.
Sensor installation:
» Thoroughly clean the pipe.
» Apply heat conducting paste A.
» Secure the sensor with a tie.
STAND-ALONE operation
In emergencies, this heat pump can also operate without the heat
pump manager (see troubleshooting).
Route all connecting cables and sensor leads through the apertures
in the back panel.
!Risk of damage!
The compressor can only turn in one direction. Should
the compressor fail to start, interchange two phases
to alter the direction of rotation. The rotating field can
be checked at the phase monitoring relay diode (see
Fig. A). The rotating field is connected correctly if the
diode illuminates.
8.8 Modules
When using a modular approach, connect the individual heat
pumps via terminal BUS 1, 2, 3. Ensure that High, Low and
Ground are correctly connected at the WPM II as well as at the
heat pump.
INSTALLATION
POWER SUPPLY
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INSTALLATION
POWER SUPPLY
X2 LV terminal
1 BUS High H
2 BUS Low L
3 BUS Ground
4 & 5 Temperature sensor B6
X3 Power supply
Heat pump (compressor)
L1, L2, L3, N, PE
X4 Control terminal
Power supply: L, N, PE
Control input:
Ext. control. STAND-ALONE operation
X5 Power supply
Brine pump
L1, L2, L3, N, PE
M Power supply WPF 20, WPF 27, WPF 40, WPF 52, WPF 66
X3
X5
X4
3/N/PE
~400V 50Hz
3/N/PE
~400V 50Hz
~230V 50Hz
X2
WPM II
BUS / Fühler
C26_03_01_0796

9 Commissioning
Only approved contractors may commission this equipment and
instruct the owner in its use.
Commission the WPF in accordance with these installation
instructions and the operating and installation instructions of the
heat pump manager WPM II. Our customer service can assist in
the commissioning, which is chargeable.
Where this heat pump is used in an installation that is intended
for commercial use, the rules of the relevant Health & Safety at
Work Act may come into play. For further details, check your local
authorising body. The function of the device, including those of
any safety equipment fitted is tested at the factory.
After commissioning, the installer should complete the
commissioning report contained in these instructions.
Check the following prior to commissioning:
Heating system
— Was the heating system filled to the correct pressure, and was
the quick-acting air vent valve opened?
Temperature sensor
— Were the outside temperature and the return temperature sensor
(in conjunction with a buffer cylinder) correctly positioned and
connected?
Power supply
— Was the mains power supply properly connected?
— The rotating field at the heat pump connection (mains) is correct
if, when power is applied to the heat pump connection (mains),
the red diode of the phase monitoring relay illuminates
(see
Fig. A)
.
—The heat pump will not start if the red diode of the phase
monitoring relay does not illuminate.
When everything has been implemented correctly, the system
can be heated to its maximum operating temperature and vented
once again.
!Risk of damage!
Observe the maximum system temperature in
underfloor heating systems.
9.1 Operation and control
A WPM II heat pump manager is required to operate the heat pump.
It regulates the entire heating system. All necessary adjustments
prior and during operation are made on this device.
Only qualified contractors must make adjustments listed in the
commissioning report of the WPM II heat pump manager.
!Risk of damage!
The system does not need to be shut down during
summer, as the WPM II implements an automatic
summer/winter changeover. If the system is,
nevertheless, to be shut down, set the WPM II to
standby. That way the safety functions that protect
the system remain enabled (e.g. frost protection).
Drain the water side of the equipment, if the heat pump is taken
out of use at a location subject to a risk of frost or if it is installed
externally.
Drain the liquid contained inside the evaporator via the fill & drain
valve that becomes accessible after removing the r.h. side panel
(pos. 11, Fig. A).
10 Maintenance
!Risk of damage!
Check the refrigerant circuit of the heat pump annually
for tightness in accordance with EU Directive 842/2006.
Document tightness tests in the service record.
If heat meters are installed, frequently clean their sieves, which
block easily.
When the heat pump operation is impaired (high pressure limiter
responds) through deposits of corrosion by-products (rust sludge)
inside the condenser, only dissolving them by means of solvents
used by our customer service will remove this problem.
!Risk of damage!
Never change the factory setting of the rotary selector
on the overcurrent circuit breaker.
Factory setting
WPF 52 35 A
WPF 66 45 A
A permanently set overcurrent circuit breaker is installed inside the
compressor of the WPF 20, 27 and 40.
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INSTALLATION
COMMISSIONING | MAINTENANCE

11 Troubleshooting
N Checking the IWS settings
BA
3
2
1
4
C26_03_01_0661
1 LEDs
2 DIP switch (S1)
3 Reset button
4 DIP switch (heat pump)
The control panel with the "Internal heat pump controller" (IWS II)
becomes accessible after removing the front hood. The following
list the adjustments of the IWS II required for the WPF:
DIP switch (heat pump)
The DIP switch (heat pump) enables the pre-selection of the
various compressor systems. Subject to the system heat pump
type, for the WPF this was set to 12 at the factory.
If the WPF is to be operated as a module with another WPF, this
setting (heat pump) remains at 12.
Please check whether the DIP switch (heat pump) is set
correctly.
The correct position of the slide switch can also be checked on
control level 3 on the WPM II. The display should indicate a C under
parameter "Type IWS".DIP switch (S1)
Switches 1 and 2 have no relevance to the WPF.
Position switch 3
Switch ON : SERVICE
Corresponding compressors (defaulted by the DIP switch setting
(heat pump)) are started in intervals of one second.
Position switch 4
Switch ON : STAND-ALONE operation
Should the WPM II heat pump manager develop a fault, the heat
pump can, in emergencies, be operated in stand-alone mode.
In this operating mode, there is no communication with the
WPM II. The system regulates to a fixed set valve: the heat pump
starts at 50 °C and stops at 55 °C. For this, 230 V must be applied
to terminal X4/2, and a temperature sensor TF 6 (part no.: 165342)
must be connected as return sensor to terminals X2/4 and 5.
Insert the sensor into the sensor well at the heating circuit return
(see Fig. A) . The operating mode is indicated by the r.h. green LED.
INSTALLATION
MAINTENANCE
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!Risk of damage!
For STAND-ALONE operation, remove the jumper
between X4/1 and 2.
As the frost sensor AVF 6 must be disconnected from
terminals X2/4 and 5 for STAND-ALONE operation, the
frost protection will be lost for external installation or
inside a room that is not safe from the risk of frost.
LEDs
Red LED: Flashing or steady:
The LED flashes when a heat pump fault occurs once.
The system will be shut down:
The red LED illuminates steady if more than 5 heat pump faults occur
within 2 hours. The system will be shut down permanently.
In both cases, the fault is entered into the WPM II fault list.
Operation can start 10 minutes after the fault has been removed;
the LED extinguishes.
To delete the faults from the IWS II, select Reset WP and reset
by pressing PRG on the IWS II. The internal counter will then be
returned to zero.
Heat pump faults displayed by the LED: High pressure fault / low
pressure fault, central fault message and hardware faults at the
IWS II (see fault list).
Green centre LED: Flashes during the initialisation and becomes
steady after the BUS address has been allocated. Communication
to the WPM II is only then established. This is only relevant for the
WPF, if the control unit is replaced, otherwise the unit is initialised
at the factory.
Green r.h. LED: Illuminates steady if STAND-ALONE operation has
been selected.
Reset button
In case of incorrect initialisation, see chapter 5.4.1 in the operating
and installation instructions of the WPM II.
INSTALLATION
TROUBLESHOOTING
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12 Specification
12.1 Standard control
O Power connection diagram for heat pumps WPF 20 / 27 / 40 / 52 / 66 with heat pump manager WPM II
C26_03_01_0800
Outside temp. semsor
Flow temp. sensor
Return temp. sensor
DHW temp. sensor
HS 2 sensor
Source temp. sensor
Mixer temp. sensor
Analog output
1 FE 7
2 FE 7
BUS H
BUS L
BUS -
BUS +
DCF
DCF
Solar
Mixer -
Mixer +
HS 2
HS 2
DHW circ. pump
DHW
Heating circuit 2
Heating circuit 1
Source
Buffer 2
Buffer 1
Pumps L
EVU L'
Mains L
Mains N
Control phase L' with
power-OFF periood
Time switch for power-OFF periods
Supply from the
domestic meter
3x1.5 mm2
2x2x0.8
Sensor Brine
pump
(Mains)
Heat pump
electricity
meter
Ext. control.
(Mains) (Mains)
X2 X1
M1 Circulation pumps (max. 2 A gl)
Supply from the domestic meter
M2 Circulation pump (three-phase)
Supply from the heat pump electricity meter
M3 Circulation pump (three-phase)
Supply from the heat pump electricity meter
INSTALLATION
TROUBLESHOOTING
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12.2 Wiring diagrams
P Wiring diagram for heat pump WPF 20 / 27
8
X2
K1
A2
A1
6
7
Q1
2 1
6
5 4 3
L
11
2 1
suB
Heißgas
12 10
9 8 7
H
Einfrierschutz
3
HD/ND Solepumpe N
5 4 3 2 1
3
4 5
L
M1
M
3
X3
X5
A2
9
10 11 12 13
X1
Fü relh
2 1
L1
L2 L3 N
K4
6
4
2
135
K1
6
4
2
135
14
L
N
X4
euetS.txEr.
1/N /PE AC 50Hz 230V
F2
> p
2
3/N/PE AC 50Hz 400V
3/N/PE AC 50Hz 400V
321
4
5
X23
X34 N3
X23
X29
X33
X30
21
1
X24
X24
C
T1
S
T2
R
T3
L1
L2 L3 N
K4
A1
A2
Q1
A2
A1
Q1
2
4
6
5
3
1
L3
L2
L1
T1
T2
T3
A1
A2
T <
E2
123
Anschluss Solepumpe
L
H
Kleinspannung
BUS
B6
B6
NO
F9
Z2
6
4
2
135
br ws sw br ws sw
3
4 5
2 1
X35
6
0
I
0
I
P3 P1
11
22
12-18V
X28
B5
C26_03_01_0853
A2 Integral heat pump controller IWS II B5 Hot gas temperature sensor B6 Frost sensor (only for ext. inst. or inst. in a room
not free from the risk of frost)
E2 Oil sump heater F2 High pressure limiter F4 Hot gas temperature limiter F6 Phase monitoring relay F9 Solar pump MCB
K1 Safety contactor K4 Brine pump contactor P1 High pressure transducer P3 Low pressure transducer Q1 Softstart contactor M1 Compressor motor N3 Temp. controller - oil sump heater X1 Terminals X2 LV terminal
X3 Heat pump - mains X4 Control voltage terminals X5 Brine pump terminals X23 Power supply earth terminal block X24 Power supply earth screw X29 Plug-in connector IWS II 12-PIN X30 Plug-in connector IWS II 3-PIN X33 Plug-in connector IWS II 5-PIN X34 Plug-in connector terminal strip - oil sump heater
INSTALLATION
SPECIFICATION
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