Pressure Testing, Filling And Flushing The System; Flushing; Pressure Testing; Filling - Meibes Solar XL Technische Information Für Montage Und Betrieb

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 valves 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 valves. 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 approved 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 Bleeding

Improper bleeding results in a drop in pressure and can lead to faults in the solar system. The temperatures of the escap-
ing air and the heat transfer medium may be greater than 60°C, therefore there is an increased risk of scalding. The air
vent is located at the highest point of the system. After bleeding, 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 valves 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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