Commissioning
Combustion analysis
23
Combustion check at full load
Start the boiler at service mode for full
load operation (
W2
). When you have
reduced P9 to 50% (see previous
chapter), the boiler will operate at 50%
load. Allow the boiler to stabilise the
combustion for 3 minutes. Then
increase P9 step by step up to 100%.
Check the gas pressure on the inlet of
the gas valve while increasing the
boiler load: the gas pressure should
never go below the minumum required
value
see technical data. Set the
minimum gas pressure switch (1) at
50% of the required gas pressure.
First check the combustion values of
the pilot burner using the measuring
tube on the back of the boiler (3). If
required the values can be corrected
with the adjustment screw on the pilot
gas valve (2).
Then check the combustion values of
the main burner using a measuring
point in the flue (4). If required the va-
lues can be corrected with the adjust-
ment screw (V) on the main gas valve
(5).
Combustion check at minimum load
Switch the boiler to service mode for
minimum load operation (
W1
). Check
the combustion settings the same way
as described for full load. The
combustion settings for the pilot burner
can be adjusted using the adjustment
screw on the pilot gas valve (6). The
combustion settings for the main burner
can be adjusted using the adjustment
screw (N) on the main gas valve (7).
Combustion check at 50% load
An additional reference check of com-
bustion values at 50% load is recom-
mended in order to check if the gas
valve is set in such way, that the modu-
lating behaviour is normal. The CO
2
value should be in between the settings
of full load and minumum load. CO
value should be equal to full load and
minimum load values.
Make sure parameter P9 is set back to
100 and switch the boiler to automatic
operation (
F
) after the combustion test
is finished.
1
Combustion settings
for natural gas G20 / G25
All boilers
CO
2, max
%
10.0 ± 0.2
CO
max
ppm
< 1000
Pilot burner
CO
2, min
%
10.2 ± 0.2
CO
min
ppm
< 1000
Combustion settings
for LPG G31
All boilers
CO
2, max
%
11.0 ± 0.2
CO
max
ppm
< 1000
CO
2, min
%
11.2 ± 0.2
CO
min
ppm
< 1000
Pilot burner
Parameter change required
P19 : 100%
►
86%
Combustion settings
for natural gas G20 / G25
All boilers
CO
2, max
%
10.0 ± 0.2
CO
max
ppm
< 30
Main burner
CO
2, min
%
9.3 ± 0.2
CO
min
ppm
< 30
Combustion settings
for LPG G31
All boilers
CO
2, max
%
11.0 ± 0.2
CO
max
ppm
< 30
CO
2, min
%
11.0 ± 0.2
CO
min
ppm
< 30
Main burner
Parameter change required
P19 : 100%
►
86%
2
6
5
7
4
3
