Checking the balanced flue system for soundness (annular
gap check)
A Combustion air apertur e
For balanced flue systems tested
together with the g as fired wall
mounted boiler, some Federal States
(e.g. Northrhein-Westphalia) waive
the requirement for a soundness test
(overpressur e test) during comm is-
sioning by the flue gas inspector.
For such cases we recommend that
your heating contractor carries out a
simple soun dness test dur ing the
initial start-up of your system. For
this, it w ould be sufficient to ch eck the
CO
2 concentration in the combustion
air at the annular gap in the balanced
flue pipe.
Thefluepipeisdeemedtobesound,
if the CO
2 concen tration of the com-
bustion air i s no higher than 0 .2 % or
the O
2 co ncentration is at least
20.6 %.
If actual CO
2 values are higher or O2
values are lo wer, carry out a pr essure
testonthefluepipeatastaticpres-
sure of 200 Pa.
Further details regarding the individual steps (cont.)
19
Initial start-up, inspection, maintenance
5692 537 GB