Pressure Testing, Filling And Flushing The System; Flushing; Pressure Testing; Filling - meibes XL Documentation Technique Pour Le Montage Et La Mise En Service

4. Pressure testing, filling and flushing the system

The following work may only be carried out by qualified specialist personnel.
When pressure testing, filling and flushing the system make sure that all shut-off fittings are open.
The collectors must be cooled down and covered to prevent injuries or damage!
On days when there is a great deal of radiation, filling should be carried out in the morning or evening.
Do not undertake any switching operations to release the pressure on the shut-off fittings. Note the flow direction for the
backflow preventer installed on the secondary side.

4.1 Flushing

Flush the system as required.
All dirt and air particles must be removed from the system before start-up. If water is used for flushing, the system should
be completely drained if there is any risk of frost at the installation site, and immediately replaced with a suitable and appro-
ved solar fluid with antifreeze.

4.2 Pressure testing

Check connections, components and joints for leak tightness.
In the event of leaks, drain the system, repair and repeat the pressure test.

4.3 Filling

Primary (solar side) : use a suitable or approved C/D solar fluid with antifreeze
Secondary (heating side) : Water (approved in accordance with VDI 2035) A/B

4.4 Venting

Improper venting results in a drop in pressure and can lead to faults in the solar system.
The temperatures of the escaping air and the heat transfer medium may be greater than 60°C, therefore there is an
increased risk of scalding. The vent is located at the highest point of the system.
After venting, the system pressure must be increased once again to the operating pressure!

4.5 Draining

When draining the system make sure that the shut-off fittings are open, before the system is
drained at the lowest point. Note the flow direction for the backflow preventer installed on the secondary side.
Ensure that the pipework is completely drained. The heat transfer fluid should be collected with a suitable collection vessel
and if necessary, disposed of in an environmentally sound manner.
Note: the system is generally under pressure! Risk of scalding!
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