Further details regarding the individual steps
Checking the expansion vessel and the system pressure
1. Drain the system. For this, close the
cap valve on the expansion vessel (if
installed) and reduce the pressure.
2. If the pre-charge pressure of the
expansion vessel is lower than the
set value, top up with nitrogen until
the pre-charge pressure equals the
set value.
Static head (top edge of collector to
expansion vessel): ........... m
Set pre-charge pressure of the
expansion vessel:
0.7 bar + 0.1 x static head in m
0.7 bar + 0.1 x ......... m = ........ bar
Checking the electrical connections
Check the tightness of the electrical
plug-in connectors and cable grommets;
check cables for damage.
Starting the heating system
Observe operating instructions of
installed components.
Commissioning, inspection, maintenance
3. Top-up heat transfer medium until the
system pressure is 0.3 to 0.5 bar
higher than the set pre-charge
pressure of the expansion vessel
(create a safety water seal in the
expansion vessel).
The safety water seal should be
0.005 x liquid content of the complete
system, but no less than 3 litres.
Liquid content of the system =
content of pipes + content of
collectors + content of the indirect coil
of the DHW cylinder and safety water
seal for the expansion vessel.
(cont.)
7