FOR THE INSTALLER
16
Perform the following steps before starting up the system.
1 - FLUSHING AND SEAL TESTING THE SYSTEM
If copper piping has been used and joints have been hot brazed, flush out the system to remove any brazing residues.
Seal test the system after you have flushed it out.
b
Fill the solar collector with anti-freeze heat transfer liquid immediately after flushing it out, because flushing water
may remain trapped in the circuit (with a consequent risk of freezing).
b
The anti-freeze fluids supplied as accessories have been specially formulated for use in solar applications, and
maintain their characteristics for their entire working life.
The mix is also non-toxic, biodegradable and biocompatible.
b
Do NOT part fill the circuit with anti-freeze then top up with water.
b
Temperatures in excess of the specified working temperature can cause the anti-freeze to break down. This is eas-
ily visible because the liquid becomes darker.
2 - FILLING
1 - Open the non-return valve (A).
2 - Open the air vent at the highest point in the system
(see figure alongside) and keep it open throughout
the filling operation.
3 - Open the vent valve (7).
4 - Pump the heat transfer fluid around the circuit with an
external filling pump until all air bubbles have been
eliminated. Close the manual bleed valve.
5 - Temporarily raise the pressure in the system to 4 bar.
6 - Start up the system for about 20 minutes.
7 - Bleed the system again from step 2 until all the air has
been removed.
8 - Set the circuit pressure at the boiler according to the
table below in order to ensure a minimum pressure of
1.5 bar at the height of the collector field.
9 - Close the non-return valve (A) and any open vent
valves to prevent the heat transfer fluid from evaporat-
ing.
FILLING THE CIRCUIT
°C
M
A
R
M
7
Manual bleed
valve (accessory)
Anti-freeze mix
Heat exchanger
of solar storage
cylinder
Solar collectors
Heat
transfer fluid
filling pump
Water control system
H
H
Pressure at boiler
up to 15 m
3 bar
15 - 20 m
3.5 bar
20 - 25 m
4 bar
25 - 30 m
4.5 bar
General rule: p [bar] = 1.5 + H [m] / 10
