Viessmann Vitocrossal 300 Service Instructions Manual page 13

Checking the CO
CO testing at the lower heating output
2
C
D
E
F
Fig. 8
B A
Fig. 9
Checking the CO content
content
(cont.)
2
1. Press "-"
mented to "0" (lower heating output).
2. Note
The CO
between 7.5 and 10.5 %.
Check the CO
content must be 0.3 % lower in partial load than it
is in full load.
Rated heating
output in kW
400
500
630
3. If the CO
■
■
4. Record the actual value in the report (on
page 54).
!
Rechecking the values
Regulate to the upper and lower heating output
again using the programming unit in the burner
control unit. If the values do not match the permis-
sible CO
page 12, repeat the steps for the upper and lower
heating output.
5. Press "S"
burner continues at the original modulation level at
which status "d" (= control stop) was initiated. The
burner then returns to operating mode.
Commissioning, inspection, maintenance
until the service display has decre-
D
content for all natural gases must be
2
content at the flue pipe. The CO
2
Permissible CO
%
8.3 0.3
±
8.3 0.3
±
8.3 0.3
±
content needs adjusting:
2
Undo cover B .
Turn adjusting screw in small increments
A
(Torx 40) until the CO content lies within the
2
specified range:
Turning clockwise
–
CO content rises
→
2
– Turning anti-clockwise
CO content falls
→
2
Please note
The CO content must always be lower in
2
partial load than it is in full load.
content according to the table on
2
and "-" simultaneously. The
E D
2
content in
2
13