Viessmann VITODENS 222-F Installation And Service Instructions Manual page 30

Commissioning, inspection, maintenance
Further details regarding the individual steps
Yes
Ignition
Yes
Gas train opens
Yes
Ionisation current
builds
Symbol A
Yes
No
Burner in opera-
tion
30
No
Fault F4
No Fault F4
No Fault F4
Stops below the
set boiler water
temperature and
restarts immedi-
ately
(cont.)
Check the ignition
module (control
voltage 230 V
across plugs
"X2.1" and "X2.2")
Check the gas train
(control voltage
230 V); check the
gas supply pres-
sure
Check the ionisa-
tion electrode
adjustment and the
gas pipe for air-
locks
Check the flue gas
system for sound-
ness (flue gas
recirculation),
check the gas flow
pressure