Buderus Logatop BE 1.3, Инструкция по установке и обслуживанию, Страница: 35 / 56

Additional service tests 8
Buderus Blue Flame Burner BE 1.3 - 2.3 - Specifications subject to change without notice. 35
8.2 Verifying tightness of fireside heating surfaces
Errors in the CO
2
reading can occur based on flue gas
leaks between the boiler block sections or leaks in the
flue gas system. A reduced CO
2
value in the venting
system compared to the CO
2
value in the combustion
chamber can result from air introduced through cracks
and vent pipe joints. Verify the validity of the CO
2
mea-
surement by performing the following test:
8.2.1 Establishing the upper limit
The burner is typically operated with a certain amount of
excess air.
When reaching the the stoichiometric limit of the fuel/air
mixture, a rapid increase in CO value will result.
The CO
2
value will also approach 14.8% when ap-
proaching the stoichiometric limit.
Proceed in the following manner:
z
Increase the oil pressure, until CO reaches 100 to
200 ppm.
z
Record the corresponding CO
2
value.
If the measured CO
2
value is below 14.3% (Deviation of
more than 0.5% in CO
2
), there is likely an air leak be-
tween the burner combustion and the test location.
z Find and close off the air leak path. Repeat the
above test to confirm that 14.8% CO
2
can be reached
as above.
8.2.2 Performing tests in the combustion chamber
Flue gas measurements are typically conducted in the
flue gas pipe (see Chapter 7.1 „Record and correct
burner measurement values“, page 24).
A direct combustion measurement in the combustion
chamber can be performed through the sight glass in the
boiler door.
When the deviation in combustion measurements be-
tween combustion chamber and venting system test port
is greater than 0.5%, a leak on the flue gas side is likely
and must be found and removed for safety reasons.
z Identify and close off flue gas leak.
After sealing of the flue gas leak, the combustion perfor-
mance of the burner should be optimized (see Chapter 6
„Initial burner start-up“, page 15).