Viessmann Vitodens 222-F B2TA Installation And Service Instructions Manual page 41

Further details regarding the individual steps
Activating the venting function
Weather-compensated control unit
Service menu
1. Press OK and å simultaneously for
approx. 4 s.
2. "Service functions"
3. "Venting"
Venting function is enabled.
4. Ending venting function:
Press OK or ä.
Commissioning, inspection, maintenance
(cont.)
Constant temperature control unit
Service menu
1. Press OK and å simultaneously for
approx. 4 s.
2. Select "5" with Ú and confirm with
OK.
"ON" flashes.
3. Activate the venting function with OK.
"EL on" is shown constantly.
4. Ending venting function:
Press ä.
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