Technical data
76
If the pressure measured by the pressure gage is not complying with the value re-
ported in Table 5.2 Network gas pressure → 31 (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.
 Fit a combustion products probe in one of the points provided for this purpose on 1. 
the external fumes equipment or at point L in Figure 7.2 Gas changeover → 80
 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 4 of the unit's controller: the 3. 
display will flash "P_H0", press to confirm forcing maximum thermal power.
 Check that the value of CO4. 
2
 read on the flue gas analyser coincides with the value 
given in Table 7.3 Gas nozzles and content of CO2 → 79 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 
between 8.7-9.3% are therefore acceptable.
 Access menu 2 parameter 3 of the unit's controller inside the electric panel: the 5. 
display will flash "P_L0", 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 → 79 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.  → 75) 
and use a Torx TX40 wrench to act on screw C in Figure 7.1 Gas valve → 75. 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 4 of the unit's controller: the 8. 
display will flash "P_H0", press to confirm forcing maximum thermal power.
 Check that, also following a regulation intervention on screw C, the value of CO9. 
2
corresponds to the value read in Table 7.3 Gas nozzles and content of CO2 → 79 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 acti-
vate the appliance; contact Robur technical service at +39 035/888111.










