72
If the pressure measured by the pressure gage is not complying with the value reported
in Table 5.2 Network gas pressure
→
33 (with a tolerance of ±15%), it is NOT possible to
switch the appliance on!
Proceed with the regulation/verification of the combustion parameters as stated
5.
in the next paragraph.
Checking and adjusting the combustion parameters
After having checked the dynamic mains pressure (see section), you may check and ad-
just the combustion parameters as follows.
Insert the combustion products analysis probe into the vertical tract of the flue gas
1.
pipe (see reference B in Figure 5.4 Fume outlet
→
37).
Give the unit functioning consent and wait for at least 5 minutes for normal com-
2.
bustion conditions.
With the appliance running, access menu 2 parameter 24 of the unit's controller:
3.
the display will flash "P_H1", press to confirm forcing maximum thermal power .
Check that the value of CO
4.
2
read on the flue gas analyser coincides with the value
given in Table 7.3 Gas nozzles and content of CO2
→
75 at the "Content of CO
2
with/MAX modulation" line with +0.2 -0.4 tolerance.
example (G20 gas): the nominal content of CO
2
is equal to 9.1%, values in the range be-
tween 8.7-9.3% are therefore acceptable.
Access menu 2 parameter 23 of the unit's controller inside the electric panel: the
5.
display will flash "P_L1", press to confirm forcing minimum thermal power.
Now check that the difference between the value read in point 4 and that now
6.
displayed on the flue gas analyser, corresponds to the data given in the Table 7.3
Gas nozzles and content of CO2
→
75 at the "Delta CO
2
between MAX and MIN
potentiality" line with tolerance of +0.3-0.0.
example (G20 gas): if at point 4 a content of CO
2
equal to 9.2% was detected, at point
6 there must be a value of (9.2%-0.4) with tolerance of +0.3 -0.0 on the delta value, i.e. a
value in the range of 8.8-8.5%.
If this is not the case, remove cap A from the gas valve (see Figure 7.1 Gas valve
7.
→
71)
and use a Torx TX40 wrench to act on screw C in Figure 7.1 Gas valve
→
71. Turn
clockwise to increase the percentage of CO
2
and anti-clockwise to decrease the
percentage of CO
2
.
1/8 turn of the regulator screw reduces (counterclockwise) or increases (clockwise) the
CO
2
content by approximately 0.1%. DO NOT turn the screw more than one full turn in
either direction.
With the appliance running, access menu 2 parameter 24 of the unit's controller:
8.
the display will flash "P_H1", press to confirm forcing maximum thermal power .
Check that, also following a regulation intervention on screw C, the value of CO
9.
2
corresponds to the value read in Table 7.3 Gas nozzles and content of CO2
→
75 at
the "Content of CO
2
with/Max modulation" line with tolerance of +0.2 -0.4.
If you cannot calibrate the CO
2
percentage after the second attempt, DO NOT activate the
appliance; contact Robur technical service at +39 035/888111.
