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

Setting the time and date (if required) - only...
Note
When time and date have been set, the control unit
automatically checks the function of the flue gas tem-
perature sensor. The display shows: "Flue gas temp
sensor test" and "Active".
For further details regarding the flue gas temperature
sensor test, see page 94.

Venting the boiler

B
A
Fig.23
1. Close the shut-off valves on the heating water side.
2. Connect the supply hose to boiler drain & fill valve
.
A
3. Plug the drain hose onto top tap
a drain.
4. Open valves and
A B
(purge) until no sound of escaping air can be heard
and no more air bubbles are visible.

Venting the heating system

1. Close the gas shut-off valve and switch the control
unit ON.
B and connect to
and vent at mains pressure
Commissioning, inspection, maintenance
(cont.)
5. Close taps A and B ; open the shut-off valves on
the heating water side.
6. Remove hoses again.
29