Connecting An Expansion Vessel (Provided On Site); Heat Transfer Medium; Pressure Test, Filling And; Flushing The System - Meibes Solarstation S Technische Information Für Montage Und Betrieb

3. Installation

3.6 Connecting an expansion vessel (provided on site)

Expansion vessels absorb the volumetric changes during
heating or cooling of the liquid and provide a liquid reserve
to compensate for minor leakages.
In accordance with the VDI guidelines, the connection
of the diaphragm expansion vessel is on the inlet side
(suction side), i.e. underneath the pump (cf. Technical Data).
Suitable, correctly designed expansion vessels
only are to be used (cf. DIN 4807).
Use backup vessels if necessary depending
on the predominant temperatures.

3.7 Heat transfer medium

Use brine solutions only with antifreeze suitable for solar systems!
Note the manufacturer and type, as these may possibly not be allowed
to be mixed with other manufacturers' media.
The following work may be carried out by trained
qualified personnel only.
When performing the pressure test (leak test), filling and
flushing the system, ensure that all shut-off fittings are open.
The collectors must be covered.
Do not undertake any switching procedures to relieve
pressure using the shut-off fitting.
4. Pressure Test, Filling and Flushing the System

4.1 Leak test

Check the connections, components and connections for leaks.
If there are any leaks, drain and repair the system and repeat the leak test.
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Expansion tank connection
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4. Pressure Test, Filling and Flushing the System

4.2 Flushing and filling

Carry out a flush of the system suited for the requirements,
doing so in accordance. Before commissioning, all particles
of soiling and air have to be removed from the system.
If water is used for flushing, if there is a danger of freezing,
the system must be completely drained or
immediately replaced with antifreeze agent.
Bear in mind that the lower shut-off on the volume flow meter
has to be closed during filling, and the ball valve handle in the
forward flow set to 45° C. This position will result in the non-return
valve being opened.
The collectors have to be covered to prevent injuries and/or damage.
Important:
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top shut-off devices : open (Position 2) (see Chapter 3)
-
bottom shut-off device : open (Position 1) (see Chapter 3)
It is important to ensure that the lower shut-off on the
volumetric flow meter is set to Position 1 during filling
(see section 3.2.) and the ball valves to 45°
(Position 2). This position opens the backflow preventer.
When the process is complete, open the lower and upper
shut-off (see section 3.2.)!
Warning (see section 3.2.):
Upper shut-off : Automatic (Position 1)
Lower shut-off : open (position 2)

4.3 Venting

Improper venting causes a pressure drop and can result
in malfunctions in the solar system.
The temperature of the escaping air and heat transfer
medium can be higher than 60 °C; therefore there is
an increased risk of scalding.
The vent is located at the highest point in the system.
After venting, increase the system pressure back to the
operating pressure!Vent occasionally at permanent
venter (optional) in operating condition.
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Permanent vent optional
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