Venting The Heating System - Viessmann VITODENS 200-W Installation And Service Instructions Manual

Commissioning, inspection, maintenance
Further details regarding the individual steps
1. Close the shut-off valves on the heat-
ing water side. If required, remove the
safety guard.
2. Push the drain hose (supplied inside
the appliance) onto top valve B and
connect to a drain.
3. Open valves A and B and vent at
mains pressure (purge) until no
sound of escaping air can be heard
and no more air bubbles are visible.
Note
Note the system pressure at the pres-
sure gauge. Do not exceed 1.5 bar.

Venting the heating system

32
4. First close valve B.
5. When the required operating pres-
sure has built up, close valve A.
Open the shut-off valves on the heat-
ing water side.
6. Remove the drain hose from top
valve B and retain.
1. Close the gas shut-off valve and
switch the control unit ON.
2. Check whether the air vent screw on
quick-action air vent valve A of the
heating circuit pump is open.
3. Activate venting program (see follow-
ing steps).
A
Note
For function and sequence of the
venting program, see page 150.
4. Adjust the system pressure.
5. Open the gas shut-off valve.
(cont.)