Vaillant geoTHERM VWS Installation Instructions Manual page 23

Check the filling level of the brine fluid
a Caution!
Risk of damage!
The filling level is correct when the brine
expansion tank is 2/3 full. The installati-
on can be damaged if the filling level is
too high.
• Top up the brine fluid when the filling level has fallen
so low that it is no longer visible in the expansion
tank.
1
Fig. 5.2 Fill level of brine expansion tank
Key to Fig. 5.2
1 Filling level too low
2 Filling level correct
The filling level of the brine fluid can fall a little in the
first month following commissioning of the system; this
is quite normal. The filling level can also vary depending
on the temperature of the heat source, but under no cir-
cumstances should it fall so far that it is no longer visib-
le in the expansion tank.
Installation instructions geoTHERM VWS 0020046310_01
Filling the heating and heat source systems 5
2
23