Commissioning And Maintenance; System Flushing; System Filling Cock - Riello 20156553 Manual

COMMISSIONING AND MAINTENANCE

13 SYSTEM FLUSHING

Before filling the system with mixture of water and glycol, it is
necessary to flush the pipes of the solar system to eliminate all
residues of fluid or scale.
Proceed as follows.
− Fit the hose holder (supplied) and connect a rubber pipe
to the taps (A) and (B)
− Turn handle on valve (VR) clockwise
− Open taps (A) and (B) on the return tube
− Flush water in through the cock (B) and wait for it to
come out of the cock (A)
− Allow water to come out for at least 30 seconds
− Turn handle on valve (VR) counter clockwise
− Close taps (A) and (B)
− Disconnect the rubber pipes and remove the hose holder
from the taps (A) and (B)
9
During system flushing, pay attention to water coming out
of the taps as vapour could be released with risk of burns or
scalds. Use suitable personal protective equipment.
Position of the knob of the valves VM - VR
0°
VM
VM
9
If copper piping has been used and joints have been hot
brazed, flush out the system to remove any brazing resi-
dues. Seal test the system after you have flushed it out.
9
The solar circuit must be immediately filled with a mixture
of water and glycol, that avoids freezing and corrosion.
Flow
90°
stopped
0°
Flow in
single direction
(non-return
valve function)
VR
PREMIXING WATER + GLYCOL
Glycol anti-freeze is supplied separately and must be premixed
with water in a suitable container before being used to fill the
system. For example, a mix of 40% glycol and 60% water pro-
vides anti-freeze protection down to a temperature of -21°C.
9
The propylene glycol supplied is specially formulated for
solar collector applications and remains fully efficient
throughout the -32 to +180°C temperature range. It is also
non-toxic, biodegradable and biocompatible.
9
Do NOT part fill the circuit with pure glycol then add water
later.
9
Do not use automatic or manual filling systems.
9
If the water supply is highly chlorinated, use distilled water
to prepare the glycol/water mix.
Anti-freeze
50%
40%
30%

14 SYSTEM FILLING COCK

90°
Before filling the system:
− Switch off the electrical supply to the station and the
combined integration system, by setting the system's
main switch to "off"
VR
9
Always use a mixture of water and glycol suitable for solar
applications. Choose the mixture according to the minimum
temperature that can be reached at the installation site and
to the maximum service temperature of solar collectors. For
further information, please refer to the glycol safety data
sheet.
When using glycol not pre-mixed:
− Do NOT part fill the circuit with pure glycol then add water
later.
− Ensure that filling water characteristics comply with pre-
vailing regulations; if that is not so, filling water must be
treated. Use portable treatment systems, for instance. In
particular, when chlorine content is very high (> 50ppm)
B
you must use distilled water for the mixture.
A
19 19
Temperature Density
-32 °C 1,045 kg/dm
-21 °C 1,037 kg/dm
-13 °C 1,029 kg/dm
3
3
3
Commissioning and maintenance