Viessmann VITOCROSSAL 200 Service Instructions Manual page 19

Further details regarding the individual steps
C D
1. Check the heating system pressure.
Permiss. operating pressure: 5.2 bar
(520 kPa)
2. In open flue operation:
Check that the installation room ven-
tilation is unobstructed.
3. Check the gas supply pressure (for
set value, see page 22).
4. Open the gas line shut-off valves.
5. Switch ON the mains isolator (outside
the installation room).
Commissioning, inspection, maintenance
(cont.)
6. Turn on the ON/OFF switch B at the
control unit.
Note
The burner will start with a delay of
approx. 3 min.
If fault indicator A on the control unit
illuminates and display C on the
burner control unit flashes, initially
reset the system. For this press reset
button D on the burner control unit.
Note
The appliance can enter a fault state
during commissioning if there is
insufficient gas in the gas line (the
fault indicator on the control unit illu-
minates). Purge the gas line again
and reset the burner control unit.
If the fault persists, the inlet strainer
of the gas train may have become
blocked by work carried out on the
gas line.
Danger
Escaping gas leads to a risk of
explosion.
First close the shut-off valves
in the gas line again.
Undo the flange on the gas train and
clean the strainer (blocked strainer is
not recognised by the gas pressure
test at the flange).
7. Adjust the codes at the boiler control
unit.
Control unit installation and
service instructions
19