Venting The Boiler; Venting The Heating System - Viessmann Vitodens 300 Service Instructions Manual

Initial start-up, inspection, maintenance
Further details regarding the individual steps

Venting the boiler

Venting the heating system

1. Close the gas shut-off valve and
start the control unit.
8
(cont.)
1. Close the shut-off valves on the
heating water side.
2. Connect the drain hose to the boiler
fill & drain valve B.
3. Open valves A and B, and vent
at mains pressure, until no sound of
escaping air can be heard.
4. Close valves A and B, and open
the primary shut-off valves.
2. Activate the venting program via
coding address 2F:1.
Note
To call up code 1 and for setting the
coding address, see page 38.
For function and sequence of the
venting program, see page 103.
3. Check the system pressure.