Nibe VVM 225 User Manual page 22

Venting the climate system
In event of repeated filling of the climate system, or if bubbling sounds
are heard from the indoor module, the system may need venting. This
is done as follows:
1. Turn off the power supply to the indoor module.
Vent the indoor module via the vent valves and the rest of the climate
2.
system via the relevant vent valves.
Keep topping up and venting until all air has been removed and the
3.
pressure is correct.
The climate system may require topping up after venting.
22 Chapter 2 | The heating installation – the heart of the house NIBE VVM 225