7 Commissioning
47
%D[L&RPEL
&2
PLQLPXP
1 to 8.6
24 Combi (C) - 28 Combi (C)
Important
Remove the Torx driver to stabilise the CO
2
value if
adjustment is required.
* Values for G20 gas type only. For G20+20%H2 calibration of the
gas valve refer to O
2
%.
Combi 2
7.4.4
Calibrating the gas valve
V
K
Gas flow rate setting screw - 4mm Allen key
OFFSET setting screw - Torx 40 (T40)
Calibration of the MAXIMUM heat input
Check that the CO
2
measured in the exhaust pipe, with the boiler
operating at maximum heat input, is as indicated in the table entitled
"Service settings".
If incorrect:
Put the boiler into chimney sweep high mode "H". Let the CO
2
value
stabilise.
Fig.5
3
Gas valve
Remove the boiler door to take measurements or make adjustments.
%D[L&RPEL
24 Combi (C) - 28 Combi (C)
&2
*
PD[LPXP
8.8 to 9.4
Important
Remove the Allen key to stabilise the CO
2
value if adjustment
is required.
Adjust the setting screw (V) located on the gas valve. Turn the screw
clockwise to increase the content of CO
2
and anti-clockwise to decrease
it.
Adjust the
Offset
setting screw located on the gas valve. Turn the
screw clockwise to increase the content of CO2 and anti-clockwise
to decrease it.
* Values for G20 gas type only. For G20+20%H2 calibration of the
gas valve refer to O
2
%.
Calibration of the REDUCED heat input
Check that the measurement in the exhaust pipe, with the boiler
operating at minimum heat input, is as indicated in the table entitled
"Service settings".
If incorrect:
Remove the Offset
setting s
crew
plug
(K)
using the Torx driver
.
The Offset setting screw is accessible after removing the Offset
setting screw plug
(K)
.
Put the boiler into chimney sweep low mode. Let the CO
2
value
stabilise.
