Stiebel eltron WPL 25 A, WPL 20 A, WPL 25 AS, WPL 20 AC, WPL 25 ACS User Manual

OPERATION AND INSTALLAT ION

Air | water heat pump

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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

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 Sound emissions ������������������������������������������������� 7

9.2 Minimum clearances �������������������������������������������� 8

9.3 Preparation of the installation location ��������������������� 8

9.4 Siting ��������������������������������������������������������������� 8

9.5 Installing supply lines and supply cables ������������������ 10

9.6 WPM heat pump manager ������������������������������������ 10

9.7 Buffer cylinder �������������������������������������������������� 10

9.8 Preparing the electrical installation ������������������������ 11

10. Installation �������������������������������������������������� 11

10.1 Handling ���������������������������������������������������������� 11

10.2 Siting �������������������������������������������������������������� 11

10.3 Heating water connection ������������������������������������� 11

10.4 Flow and return connection ���������������������������������� 12

10.5 Fitting the push-fit connector �������������������������������� 12

10.6 Oxygen diffusion ������������������������������������������������ 13

10.7 Filling the heating system ������������������������������������ 13

10.8 Minimum flow rate ��������������������������������������������� 13

10.9 Setting the flow rate on the heating side ������������������ 13

10.10 Condensate drain ����������������������������������������������� 15

10.11 External second heat generator �����������������������������15

10.12 Safety temperature controller for underfloor heating
system STB-FB �������������������������������������������������� 15

11. Power supply ����������������������������������������������� 15

11.1 Power connection WPL15AS| WPL15ACS ��������������� 17

11.2 Power connection WPL20A| WPL20AC| WPL25A|
WPL25AC �������������������������������������������������������� 17

11.3 Power connection WPL25AS| WPL25ACS ��������������� 18

11.4 Electrical connection of supplementary heating facility 18

12. Commissioning ��������������������������������������������� 20

12.1 Checks before commissioning�������������������������������� 20

12.2 Using the appliance with an external second heat
generator ��������������������������������������������������������� 20

12.3 Settings ����������������������������������������������������������� 20

12.4 Operation and control ����������������������������������������� 21

12.5 Decommissioning ����������������������������������������������� 21

13. Maintenance ������������������������������������������������ 21

14. Troubleshooting �������������������������������������������� 22

14.1 Checking the IWS DIP switch settings ���������������������� 22

14.2 Light emitting diodes (LEDs) ����������������������������������23

14.3 Reset button ����������������������������������������������������� 24

14.4 Resetting the high limit safety cut-out ��������������������� 24

14.5 Fan noise ��������������������������������������������������������� 24

15. Specification ������������������������������������������������ 26

15.1 Dimensions and connections ��������������������������������� 26

15.2 Wiring diagram for WPL15AS| WPL15ACS|
WPL25AS| WPL25ACS (single-phase) ������������������� 28

15.3 Wiring diagram for WPL20A| WPL20AC| WPL25A|
WPL25AC (3-phase) �������������������������������������������30

15.4 Output diagrams WPL15AS| WPL15ACS ���������������� 32

15.5 Output diagrams WPL20A| WPL20AC ��������������������34

15.6 Output diagrams WPL25A| WPL25AC| WPL25AS|
WPL25ACS ������������������������������������������������������ 36

15.7 Data table �������������������������������������������������������� 38

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 up and persons with reduced physical, sen­sory or mental capabilities or a lack of experience
and know-how provided that they are supervised
or they have been instructed on how to use the
appliance safely and have understood the result­ing risks. Children must never play with the ap­pliance. Children must never clean the appliance
or perform user maintenance unless they are
supervised.

- Use a permanent connection to the power supply.
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.

- Maintain the minimum clearances to ensure trou­ble-free operation of the appliance and facilitate
maintenance work.

- Maintenance work, such as checking the electri­cal 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).

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 appli­ance 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

- Following isolation from the mains supply, parts
of the appliance may remain live for up to 2 min­utes since the capacitors still have to discharge
into the inverter.

- Never interrupt the power supply, even outside
the heating period. The system’s active frost pro­tection is not guaranteed if the power supply is
interrupted.

- If the heat pump and frost protection are com­pletely switched off, drain the system on the
water side.

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.

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OPERATION

Safety

1.2 Other symbols in this documentation

Note

General information is identified by the symbol shown
on the left.

 Read these texts carefully.

Symbol Meaning

!

 This symbol indicates that you have to do something. The ac-

tion you need to take is described step by step.

Material losses
(appliance and consequential losses, environmental pol­lution)

Appliance disposal

1.3 Units of measurement

Note

All measurements are given in mm unless stated oth­erwise.

1.4 Standardised output data

Explanations to determine and interpret the specified standardised
output data.

1.4.1 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.
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 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 test conditions defined in the first
paragraph 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 ac­cordance with the test conditions defined in the first paragraph
of this section.

2. Safety

2.1 Intended use

Observe the application limits listed in chapter "Specification /
Data table".

This appliance is intended for domestic use. It can be used safely
by untrained persons. The appliance can also be used in a non-do­mestic 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 inappropri­ate. Observation of these instructions and of 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 should carry out the electrical
work and installation of this appliance.

- The qualified contractor is responsible for adherence to all
currently applicable instructions 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 capa­bilities or a lack of experience and know-how provided
that they are supervised or they have been instructed
on how to use the appliance safely and have understood
the resulting risks. Children must never play with the
appliance. Children must never clean the appliance or
perform user maintenance unless they are supervised.

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OPERATION

Appliance description

3. Appliance description

3.1 Properties

The appliance is a heating heat pump for outdoor installation that
operates as an air | water heat pump. 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 65°C.

The appliance is equipped with an electric emergency/booster
heater (DHC). If the dual mode point can no longer be maintained
in mono mode operation, the electric emergency/booster heat­er is activated to safeguard heating operation and the provision
of high DHW temperatures. In such cases, the electric emergen­cy/booster heater is activated in mono energetic operation 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 –20 °C outside
temperature.

- 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.

Note

For centralised control of the heating system you will
need heat pump manager WPM.

3.2 Function

3.2.1 Heating

Heat is extracted from the outdoor air via the heat exchanger
(evaporator) on the air side. The evaporated refrigerant is com­pressed by a compressor. Electrical energy is necessary for this
process. At this point, the refrigerant is at a higher temperature
level. A further heat exchanger (condenser) transfers the heat to
the heating circuit. During this process, the refrigerant expands,
and the cycle restarts from the beginning.

At air temperatures below approx. +7 °C, the humidity in the air
condenses as hoarfrost on the evaporator fins. Any hoarfrost is
automatically defrosted. Water created by this process collects in
the defrost pan and is drained off via a hose.

The heat pump automatically reverts to heating mode at the end
of the defrost cycle.

Material losses

!

In dual mode operation, the return water of the second
heat generator can 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.

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 by the WPM heat pump manager.

 Please observe the heat pump manager operating and instal-

lation instructions.

Material losses

!

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. For operation without a
buffer cylinder, observe chapter „Operation / Menu struc­ture / Menu SETTINGS/ STANDARD SETTING / BUFFER
OPERATION“ in the operating and installation instructions
of the WPM. Otherwise the heating water freezes under
unfavourable conditions.

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OPERATION

Maintenance and care

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.

Regularly check the condensate drain (visual inspection). Remove
contamination and blockages immediately (see chapter "Installa­tion/ Condensate drain").

1.

2.

1

1 Inspection port

6. Troubleshooting

Fault Cause Remedy

There is no hot
water or the heat­ing system stays
cold.

The external unit
leaks water.

This can cause the
humidity in the
outdoor air to ac­cumulate as dew or
frost on the cooled
heat pump casing

Note

Even when the condensate is draining away correctly,
expect water to drip from the appliance onto the floor.

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.

D0000037831

Sample type plate

No power at the appliance.

The condensate drain may be
blocked.

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.

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.

Clean the condensate drain
as described in „Mainte­nance and care“.

Material losses

!

Keep the air discharge and intake apertures free from
snow and leaves.

We recommend an annual inspection (to establish the current con­dition of the system), and maintenance by a qualified contractor if
required (to return the system to its original condition).

Protect the appliance from dust and dirt ingress during building
work.

Montageanweisung beachten! Dichtheit geprüft!

1 Number on the type plate

Made in Germany

*xxxxxxxxxxxxxxxxxx*

1

26�03�01�1736

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INSTALLATION

Safety

INSTALLATION

7. Safety

Only a qualified contractor should carry out installation, commis­sioning, 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 offers frost protection for the connection lines. 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 sec­tions. 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

9. Preparations

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 Sound emissions

The appliance is louder on the air intake and air discharge sides
than on the two enclosed sides. Observe the following information
when selecting the installation location.

Note

For details regarding the sound power level, see chapter
"Specification / Data table".

- 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.

 Ensure that the air intake direction is the same as the main

wind direction.

 Air should not be blown out against the wind.
 Never direct the air intake or discharge towards noise-sensi-

tive rooms of the house, e.g. bedrooms.

 Avoid installation on large, echoing floor areas, e.g. tiled

floors.

 Avoid installation between reflective building walls. Reflect-

ing building walls can increase the sound level.

 Maintain the minimum clearances to ensure trouble-free op-

eration of the appliance and facilitate maintenance work.

8.2 Accessories

8.2.1 Required accessories

- Heat pump manager in wall mounting enclosure, WPM

8.2.2 Further accessories

- Remote control for heating systems FEK

- Remote control for heating systems FE7

- Ribbon heater HZB-1

- Ribbon heater HZB-2

- Safety temperature controller for underfloor heating system
STB-FB

- T-support SK-WPL

- Wall mounting support WK 2

- Mounting bracket MK 1

- Connection set AS-WP 1

- Connection set AS-WP 2

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INSTALLATION

750

Preparations

9.2 Minimum clearances

≥1000

≥800

≥300

≥500

9.4 Siting

Note

If the condensate drain hose is not laid with frost protec­tion or is exposed to severe weather conditions, instal­lation of a ribbon heater is recommended both with the
plinth and the wall mounting support.

9.4.1 Example: Pipe routing above ground or mounting
bracket MK 1

- The substrate must be horizontal, level, solid and permanent.
 Ensure the entire appliance frame is in full contact with the

substrate. Uneven substrates can increase noise emissions.

If the supply lines are run downwards through the ground, they
must be laid in a recess (space) in the foundation.

WPL15AS| WPL15ACS

1

3

200

140

4

1300

75

≥2000

 Do not install the appliance in a recess. Two sides of the ap-

pliance must remain exposed.

9.3 Preparation of the installation location

 Observe chapter “Sound emissions”.
 Ensure that the appliance is accessible from all sides.

5

100

D000002829991�00�00�0036

410

2

1 Air intake
2 Air discharge
3 Main wind direction
4 Supply line recess
5 Condensate drain recess (minimum diameter 70mm)

 Ensure that the foundations offer the necessary recess.

D0000034133

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INSTALLATION

750

6

1

Preparations

WPL20A| WPL20AC| WPL25A| WPL25AS| WPL25AC|
WPL25ACS

1

3

200

140

4

5

100

410

1 Air intake
2 Air discharge
3 Main wind direction
4 Supply line recess
5 Condensate drain recess (minimum diameter 70mm)

 Ensure that the foundations offer the necessary recess.

1500

75

2

 Hook two brackets respectively into the lateral slots on the

front and back. Ensure you are using the correct brackets for
the left and right hand slots respectively.

 Position the brackets so that the groove on the bracket is

D0000028298

hooked into the appliance.

 Secure the appliance to the foundations using the brackets

and suitable rawl plugs and screws.

Note

 Do not use the screws with which the appliance was

secured to the transport pallet.

D0000064201

Example: Laying pipes above ground

Example: Mounting bracket MK 1 (only WPL15AS |
WPL15ACS)

Note

The mounting bracket cannot be used in combination
with the connection sets (AS-WP1 and AS-WP2).

4

5

1

2

A

7

3

8

A 100
B 300
C Depth of frost line
1 Heating flow

5

2

1

AB

3

C

4

D0000028297

2 Heating return
3 Condensate drain
4 Condensate drain pipe
5 Foundation
6 Gravel bed

A Depth of frost line
1 Heating flow

6

D0000060818

2 Heating return

Note

The transport brackets can be used to secure the appli­ance to the foundations.

3 Conduit for supply lines
4 Foundation
5 Mounting support
6 Gravel bed
7 Drainage pipe
8 Condensate drain

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INSTALLATION

Preparations

9.4.2 Example: T-support SK-WPL

1

A Depth of frost line
B 300
1 Heating flow
2 Heating return
3 Conduit for supply lines/cables
4 Foundation
5 T-support
6 Gravel bed
7 Drainage pipe
8 Condensate drain
9 Cover

 Observe the static limits of the T-support used.

9.4.3 Example: Wall mounting support WK 2

2

4

9

B

A

3

7

6

Note

To prevent disturbance due to structure-borne noise
transmission, never install the wall mounting bracket on
the external walls of living areas or bedrooms.

 Install the wall mounting bracket, for example, on a

garage wall.

8

5

9.5 Installing supply lines and supply cables

The supply lines are all electric cables plus the heating flow and
return lines.

 Use only weather-resistant cables, e.g. NYY.
 Protect the flow and return lines against frost, with sufficient

thermal insulation. Provide the thermal insulation in accord­ance with applicable regulations.

 Also protect all supply lines/cables against humidity, damage

D0000050006

and UV radiation by means of a conduit.

 Protect the supply lines and cables routed through the

ground from moisture and damage by routing them through
a conduit.

 Protect all pipe fixings and outer wall transitions with an-

ti-vibration insulation.

Note

When routing the condensate hose, observe chapter "In­stallation / Condensate drain".

9.6 WPM heat pump manager

A WPM heat pump manager is required to operate the appliance.
This controls the entire heating system.

≥300

3

1

2

1 Heating flow
2 Heating return
3 Condensate drain
4 Drainage pipe
5 Wall mounting bracket

 Observe the static limits of the wall mounting support used.

4

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 a buffer cylinder, observe the de-

5

D0000058719

tails specified in chapter „Minimum flow rate with individual
room controller by means of FEK / FE7 in the case of systems
without buffer cylinder“.

Material losses

!

A buffer cylinder with diffusion-proof insulation is essen­tial for cooling mode.

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INSTALLATION

Installation

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!
Use a permanent connection to the power supply. 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. Ob­serve 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).

 Lay the relevant pipe cross-sections. Observe the applicable

national and regional regulations.

Fuse protection Assignment Cable cross-section

10. Installation

Note

The device is designed in such a way that it can be po­sitioned and connected without removing the cover or
side panels.

10.1 Handling

 Use the recessed grips provided at the sides.

Material losses

!

Protect the appliance against heavy impact during
transport.

Only allow the appliance to be tilted during transport for a short
time to one of its longitudinal sides. The longer the appliance is
tilted, the greater the distribution of refrigerant oil in the system.
Wait approx. 30 minutes before starting the appliance after it has
been tilted.

10.2 Siting

 When installing the appliance, observe the air intake

direction.

 Position the standard appliance on the prepared substrate.

1x C 20 A

1x C 35 A

3x C 16 A

2x B 16 A

3x B 16 A

1x B 16 A Control 1.5 mm²

The electrical data is provided in the "Specification" chapter. You
require a J-Y (St) 2x2x0.8mm² cable as BUS cable.

Note

The appliance contains an inverter for the variable speed
compressor. In case 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.

Heat pump
(single phase)
WPL 15 AS
WPL 15 ACS

Heat pump
(single phase)
WPL 25 AS
WPL 25 ACS

Heat pump
(3-phase)
WPL 20 A
WPL 20 AC
WPL 25 A
WPL 25 AC

Electric emer­gency/booster
heater WPL15AS
WPL15ACS
WPL25AS
WPL25ACS

Electric emergen­cy/booster heater
WPL 20 A
WPL 20 AC
WPL25A
WPL25AC

 Make sure that the appliance power supply is dis-

connected from the fuse board/distribution panel.

2.5 mm² for routing above the surface

4.0 mm² for routing through a wall

6.0 mm² for routing through a wall

2.5 mm²

2.5 mm²

2.5 mm²

Note

The appliance can be secured to a foundation with screws
as additional protection against tipping over.

 Use the accessories that were in place to secure the

appliance to the transport pallet.

10.3 Heating water connection

The heat pump heating system must be connected by a qualified
contractor in accordance with the water installation drawings,
which are part of the technical guides.

 Thoroughly flush the pipework before connecting the heat

pump. Foreign bodies, such as welding beads, rust, sand,
sealant, etc. can impair the operational reliability of the heat
pump.

 Connect the heat pump on the heating water side. Check for

tightness.

 Ensure the correct connection of the heating flow and return.

To facilitate connection to the heating system, push-fit connectors
are enclosed with the appliance (see chapter "Fitting the push-fit
connectors").

 Provide the thermal insulation in accordance with applicable

regulations.

 When designing the heating circuit, observe the internal

pressure difference (see chapter "Specification / Data table").

www.stiebel-eltron.com WPL A | WPL AC | WPL AS | WPL ACS | 11

INSTALLATION

Installation

10.4 Flow and return connection

Material losses

!

Insulate the heating flow and return lines for cooling
mode with vapour diffusion-proof material.

 Take the position of the heating flow and return from the fol-

lowing figure:

1

2

4

3

1 Heating flow
2 Heating return
3 Drain
4 Ventilation

 Connect the heat pump to the heating circuit. Check for

tightness.

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.

3

2

1

1 Retainer
2 Screw cap
3 Gap between screw cap and main body
4 Main body

26�03�01�1871

Pipe Ø 28 mm
Depth of insertion A 44 mm

4

26�03�01�0693

26�03�01�0693

10.5 Fitting the push-fit connector

Note

The plastic push-fit connectors are not suitable for instal­lation in the DHW line or the solar circuit.

 Only install the push-fit connectors in the heating or

brine circuits.

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 stain­less steel serrations and an O-ring seal. In addition, the push­fit connectors are equipped with the “twist and lock” function.
Simply turning the screw cap by hand will secure the pipe in the
connector and push the O-ring against the pipe to seal it.

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 there is a narrow gap

of approx. 2mm. Press the retainer back with your fingers
and hold on to it.

 Pull out the inserted pipe.

26�03�01�0693

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