Checking The Combustion Quality - Viessmann VITODENS 343-F WS4A Installation And Service Instructions Manual

Further details regarding the individual steps

Checking the combustion quality

The electronic combustion control unit automatically ensures an optimum com-
bustion quality. Only the combustion values need to be checked during commis-
sioning and maintenance. For this, check the CO
description of the electronic combustion control unit, see page 127.
CO or O content
2 2
The CO content must be within the following ranges (upper and lower output):
2
7.7 to 9.2 % for natural gas E and LL
9.3 to 10.9 % for LPG P
For all gas types, the O
If the actual CO or O
2 2
the following steps:
Check the balanced flue system for soundness, see page 35.
Check the ionisation electrode and connecting cable, see page 38.
Check the parameters of the combustion control unit, see page 112.
Note
During commissioning, the combustion control unit carries out an automatic
calibration. This may lead to CO emissions in excess of 1000 ppm for a short
time.
Commissioning, inspection, maintenance
content must be between 4.4% and 6.9 %.
2
values lie outside their respective ranges, proceed with
1. Connect a flue gas analyser at flue
gas port A on the boiler flue con-
nection.
2. Open the gas shut-off valve, start
the compact boiler and create a
heat demand.
3. Adjust the lower output.
(cont.)
or O content. For a function
2 2
Press both keys 9 and d simul-
taneously until the display shows
"Relay test".
With a/b in the display, select
"Base load".
45