Viessmann Vitodens 222-F B2TA Installation And Service Instructions Manual page 18

Installing the boiler
Gas connection
!
Please note
Excessive test pressure may
damage the boiler and the gas
valve.
Max. test pressure 150 mbar
(15 kPa). Where higher pres-
sure is required for tightness
tests, disconnect the boiler
and the gas valves from the
gas supply pipe (undo the fit-
ting).
18
(cont.)
3. Vent the gas line.
Conversion to other gas types:
See page 44.