Combustion Test (Co2); Combustion Adjustment Function (Co2); Gas Valve - Baxi NUVOLA DUO-TEC GA 16 Instruction Manual For Users And Fitters

12.4 COMBUSTION TEST (CO2%)
For correct boiler operation, the content of (CO2- O2)in the combustion fumes must observe the tolerances indicated in the fol-
lowing table. If the value of (CO2- O2)is different, check the electrodes and their relative distances (chapter 16.2). If necessary,
replace the electrodes and position them correctly. If the problem persists, use the following function.
CO
Nominal value 8,7
Admitted value 8,0 - 9,4
The combustions analisys shall be done using an analyzer regularly calibrated.
During normal operation the boiler performs combustion control cycles. In this phase, CO values higher than 1000 ppm can
occur for brief periods of time.
COMBUSTION ADJUSTMENT FUNCTION (CO2%)
This function sets out to partially adjust the value of CO2%. The following procedure is used.
• Press buttons and
seconds followed by programme row "304" alternated with the % of boiler power.
• After the burner is lit, the boiler reverts to maximum DHW power (100). When the display shows "100" it is possible to partially
adjust the value of CO2 %;
• press . The display shows "00" alternating with the function number "304" ( flashes);
• press to raise or lower the amount of CO2 (from -3 to +3).
• press to save the new value and view the power value "100" on the display again (the boiler continues operating at maxi-
mum DHW power).
This procedure can also be used to adjust the quantity of CO2 to the ignition power and to the minimum power by pressing
after point 5 of the procedure described above.
• After saving the new value (point 5 of the procedure), press
CO2 to stabilise and then adjust as described in point 4 of the procedure (the power value is a number <> 100 and <> 0) then
save (point 5).
again to take the boiler to minimum power. Wait for the value of CO2 to stabilise and then adjust as described in
• press
point 4 of the procedure (power value = 00);
• to exit the function, press the buttons for at least 6 seconds as described in point 1.

13. GAS VALVE

Gas valve key
Pi
Gas supply pressure tap
7105978.01 (1-08/11)
G20
% O % CO
2 2
5,4 10,0
6,6 - 4,1 9,2 – 10,8
together for at least 6 seconds. When the function is enabled, the displays shows "On" for a few
G31
% O %
2 2
5,7
6,9 - 4,4
to take the boiler to its ignition power. Wait for the value of
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