PAW SolexMidi TW Service manual

PAW GmbH & Co.KG
Böcklerstr. 11, D-31789 Hameln, Germany
Phone: [phone], Fax: [phone]
E-mail: [email protected], Web: www.paw.eu
2017/05 99609x4x5-mub-en –V05 1
Installation and Operation Instructions
Transfer Stations:
SolexMidi TW - DN 20
SolexMaxi TW - DN 25
[hydraulics]
SolexMidi TW
SolexMaxi TW

1 General Information
2 99609x4x5-mub-en –V05 2017/05
Item no. 99609x4x5-mub-en –Version V05 –Issued 2017/05
Translation of the original instructions
We reserve the right to make technical changes without notice!
Printed in Germany –Copyright by PAW GmbH & Co. KG
PAW GmbH & Co.KG
Böcklerstraße 11
D-31789 Hameln, Germany

1 General Information
2017/05 99609x4x5-mub-en –V05 3
Contents
s1 General Information ...........................................................................................................4
1.1 About these instructions ............................................................................................... 4
1.2 About this product ........................................................................................................ 5
1.3 Designated use ............................................................................................................ 6
2Safety instructions .............................................................................................................7
3Assembly and installation [specialist] ..................................................................................9
3.1 Controller connection ................................................................................................. 11
4Commissioning [specialist] ...............................................................................................12
4.1 Preparations before flushing and filling....................................................................... 13
4.2 Flushing and filling the secondary circuit .................................................................... 13
4.3 Flushing and filling the solar circuit............................................................................. 14
4.4 Parameters: SolexMidi / SolexMaxi with controller SC5.14......................................... 19
5Maintenance [specialist] ...................................................................................................20
5.1 Draining the solar station............................................................................................ 21
5.2 Deinstallation.............................................................................................................. 21
6Spare parts [specialist].....................................................................................................22
6.1 Spare parts control and insulation SolexMidi TW (6095436) ...................................... 22
6.2 Spare parts hydraulics SolexMidi TW (6095436)........................................................ 23
6.3 Spare parts control and insulation SolexMaxi TW (6096465) ..................................... 24
6.4 Spare parts hydraulics SolexMaxi TW (6096465)....................................................... 25
7Technical data .................................................................................................................26
7.1 Dimensional drawing SolexMidi TW ........................................................................... 27
7.2 Dimensional drawing SolexMaxi TW .......................................................................... 27
7.3 Pressure drop characteristics SolexMidi TW .............................................................. 28
7.4 Pressure drop characteristics SolexMaxi TW ............................................................. 28
8Function of the check valves [Expert]................................................................................29
9Commissioning report ......................................................................................................31

1 General Information
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1General Information
Carefully read these instructions before installation and commissioning.
Save these instructions in the vicinity of the installation for future reference.
1.1 About these instructions
These instructions describe the functioning, installation, commissioning and operation of the
SolexMidi TW and SolexMaxi TW transfer stations for charging buffer tanks or domestic hot
water tanks. The chapters called [specialist] are intended for specialists only.
For other components of the solar installation, such as pumps, collectors, storage tanks or
expansion tanks, please observe the instructions of the corresponding manufacturer.
DN 20
Item number
Controller
SC5.14
Flow rate
(maximum)
Collector surface
(maximum)
SolexMidi
TW
6095436
1200 l/h
50 m²
DN 25
Item number
Controller
SC5.14
Flow rate
(maximum)
Collector surface
(maximum)
SolexMaxi
TW
6096465
2000 l/h
100 m²

1 General Information
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1.2 About this product
The station is a premounted group of valves and fittings checked for leakage and used to
transfer the heat from the primary (solar circuit) to the secondary circuit (heating circuit or
domestic hot water circuit).
It contains a preset controller as well as important fittings for the operation of the system:
Ball valves in the primary circuit (flow and return)
Piston valves in the secondary circuit (flow and return)
Check valves to avoid involuntary gravity circulation in the flow and return of the solar
circuit, non return valve in the return of the secondary circuit
Pressure relief valves to prevent inadmissible overpressures in the station
Pressure gauge for displaying the installation pressure in the primary circuit
Vent valves to easily vent the primary circuit and the secondary circuit
Fill and drain valves with caps to flush, fill and drain the primary circuit
A flow meter (FlowRotor) and temperature sensors for heat quantity balancing (primary)
In the heating circuit, the installation must be equipped with a safety group, that can be ordered
separately.
The expansion tank required for operation must be adapted to the size and the requirements of
the installation and must be ordered separately.
The cap-type valve (DN 20: item no. 5302, DN 25: item no. 5301), which is also separately
available, allows the expansion tank to be easily mounted and separated from the solar thermal
system.
The wrapping materials are made of recyclable materials and can be disposed of with
recyclable materials.

1 General Information
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1.3 Designated use
The station may only be used as a transfer station between the solar and the domestic hot
water circuit or storage tank in solar thermal systems taking into consideration the technical limit
values indicated in these instructions. Due to its design the station must be mounted and
operated as described in these instructions!
Only use PAW accessories with the transfer station.
Improper usage excludes any liability claims.
When the sun shines, the collectors can become very hot.
The solar fluid in the circuit can heat up to more than 100 °C.
Only flush and fill the solar circuit when the collector temperatures are
below 70 °C.
Schematic structure
SolexMidi / SolexMaxi
Scope of delivery

2 Safety instructions
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2Safety instructions
The installation and commissioning as well as the connection of electrical components require
technical knowledge commensurate with a recognised vocational qualification as a fitter for
plumbing, heating and air conditioning technology, or a profession requiring a comparable level
of knowledge [specialist]. The following must be observed during installation and
commissioning:
Relevant local and national regulations
Accident prevention regulations of the professional association
Instructions and safety instructions mentioned in this manual
WARNING
Danger of scalding due to vapour escape!
With pressure relief valves there is risk of scalding due to vapour escape.
During installation, check the local conditions and if a discharge line must be
connected to the safety group.
Observe the instructions regarding the pressure relief valve.
The pressures calculated by the installation planner for the expansion tank
and the operating pressure of the installation must be set.
WARNING
Personal injury due to polluted potable water!
The heating water contains harmful substances, that must not be washed into the
domestic hot water circuit.
If the station was used for charging a buffer tank there is still, after draining,
heating water in the valves and fittings and in the pump of the secondary circuit. It
can not be removed without residue.
The station must not be connected to a domestic hot water circuit.

2 Safety instructions
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CAUTION
Risk of burns!
The valves and fittings and the pumps can become heated up to more than
100 °C during operation.
The shell must remain closed during operation.
CAUTION
Personal injury and damage to property due to overpressure!
By closing the two ball valves in the primary circuit you isolate the pressure relief
valve from the heat exchanger. A rise in temperature in the storage tank will
cause high pressures and could result in personal injury or damage to property!
Only close the ball valves for service and maintenance.
If you close the ball valves in case of servicing, do also put the pumps out
of operation and close the ball valves in the secondary circuit.
NOTICE
Material damage due to mineral oils!
Mineral oil products cause lasting damage to seals made of EPDM, whereby the sealant
properties are lost. We do not assume liability nor provide warranty for damage to property
resulting from sealants damaged in this way.
It is imperative to avoid that EPDM gets in contact with substances containing mineral
oils.
Use a silicone- or polyalkylene-based lubricant free of mineral oil such as Unisilikon
L250L and Syntheso Glep 1 from Klüber or a silicone spray.

3 Assembly and installation [specialist]
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3Assembly and installation [specialist]
The location of installation must be dry, load-carrying, frost-proof and protected against
ultraviolet radiation to prevent material damage to the installation. Furthermore, the access to
the control and safety equipment must be guaranteed at all time during operation!
The discharge line of the safety equipment should be guided into a heat-resistant container with
corresponding size. This allows you to avoid uncontrolled discharging into the environment and
to easily refill the circuits!
NOTICE
Material damage due to high temperatures!
Install the fitting group at a sufficient distance from the collector field, since the solar fluid may
be very hot near the collector.
It may be necessary to install an intermediate tank in order to protect the expansion tank.
1. You can use a drilling template in order to facilitate the
installation, which you can find on the station.
2. Copy the mounting holes to the mounting surface.
3. Drill the holes and insert appropriate wall plugs into the
holes.
4. Screw in the screws and let them stick about 4 cm out of
the wall.
5. Remove the station from the packaging.
6. Remove the insulating front shell. Hang the module onto
the screws and tighten the screws.
WARNING
Personal injury due to polluted potable water!
The heating water contains harmful substances, that must not be washed into the
domestic hot water circuit.
If the station was used for charging a buffer tank there is still, after draining,
heating water in the valves and fittings and in the pump of the secondary circuit. It
can not be removed without residue.
The station must not be connected to a domestic hot water circuit.

3 Assembly and installation [specialist]
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7. Connect the transfer station to the system:
①Solar flow from the collector
②Solar return to the collector
③Flow to the storage tank
④Return from the storage tank
The screw connections in the primary circuit of the
SolexMidi have ¾" internal threads and in the secondary
circuit 1" external threads.
The screw connections in the primary circuit of the
SolexMaxi have 1" internal threads and in the secondary
circuit 1¼" external threads.
8. Mount the safety group, consisting of the pressure relief
valve [c], the fill valve [d] and the manometer [e] to the
connection of the return ball valve [b].
9. Connect the pipe for the expansion tank below the
pressure gauge and fix the bracket for the expansion
tank.
During servicing at the expansion tank, we recommend
the installation of a cap valve (DN 20: item no. 5302,
DN 25: item no. 5301) on the expansion tank.
NOTICE
Note regarding the expansion tank
The expansion tank must not be connected while flushing and filling in order to avoid that dirt
particles are washed in.
10. Pressurise the expansion tank as specified by the
manufacturer and connect the expansion tank.
Observe the separate instructions regarding the
expansion tank!
11. Check all screw connections and tighten them if
necessary.