Viessmann VITODENS 050-W Installation And Service Instructions Manual page 45

Further details regarding the individual steps
Commissioning, inspection, maintenance
(cont.)
5. Set the lower heating output and
check the CO
2
The CO content must be between
2
0.3 and 0.9 % below the value of
the upper heating output.
6. ■ If the CO content is within the
2
indicated range, continue with
point 8.
■ If the CO content is not within
2
the indicated range, check the
balanced flue system for tight-
ness; remedy any leaks.
Replace gas train if required.
7. Re-check the CO
upper and lower heating output.
8. Shut down the boiler. Remove flue
gas analyser. Seal flue gas aper-
ture A.
content.
content for the
2
45