Combustion Adjustment - Riello 40 Series Installation, Use And Maintenance Instructions

COMBUSTION ADJUSTMENT

In conformity with Efficiency Directive 92/42/EEC the application of the burner on the boiler,
adjustment and testing must be carried out observing the instruction manual of the boiler, includ-
ing verification of the CO and CO
average temperature of the water in the boiler.
It is advisable to set the burner according to the type of gas used and following the indications of the
table:
EN 676
Theoretical max. CO
GAS
0 % O
G 20 11.7
G 25 11.5
G 30 14.0
G 31 13.7
IONIZATION CURRENT
The minimum current required by the control box is 3 µA.
The burner would normally have a higher current value than this, but if a check is required, open
the connector fitted in the red probe lead and inser t a microammeter as shown.
Control box
terminal block
AIR PRESSURE SWITCH
The air pressure switch is set after all other adjustments have
been made. Begin with the switch at the lowest setting.
With the burner working at the minimum output, adjust the dial
clockwise, increasing its value until the burner shuts down.
Now reduce the value by one set point, turning the dial anti-clock-
wise.
Check for reliable burner operation, if the burner shuts down, re-
duce the value by a half set point.
Attention:
To comply with the standard, the air pressure switch must operate when the CO value exceeds
1% (10,000 ppm).
To check this, insert a combustion analyser in the flue, slowly reduce the burner air setting and
verify that the burner shuts down by the action of the air pressure switch before the CO value
exceeds 1%.
2425
concentration in the flue gases, their temperatures and the
2
AIR EXCESS: max. output λ ≤ 1.2 – min. output λ ≤ 1.3
Setting CO
2
λ = 1.2
2
9.7
9.5
11.6
11.4
10
%
2
λ = 1.3
9.0
8.8
10.7
10.5
Connector
Ionization probe
8
GB
NO
CO
mg/kWh
mg/kWh
≤ 100 ≤ 170
≤ 100 ≤ 170
≤ 100 ≤ 230
≤ 100 ≤ 230
D5006
D5049
x