45
Gas pipe
Mixer
Gas valve
fig. 17
3.7.3. Checking and adjusting the gas valve
PREAMBLE
Through the "BEST” function, the boiler adapts automatically the combustion to the installation conditions, therefore the following proce-
dure is to be carried out after the chimney sweep function if the gas calibration values do not match those on the plate or if the electronic
board, the electrode, the fan or the gas valve have been replaced.
The boiler must be ready for operation, the air must be bleed out and the heating function must be enabled. The procedure can begin in
two different manners, depending on the parameter "P14” value:
AUTO
("P14" = 5): the boiler performs 10 ignition attempts by gradually increasing power values;
MANU
("P14" = 0): the boiler performs 5 ignition attempts at the power value indicated in the parameter "P31".
After the burner ignition, the boiler performs a cycle with minimum power "P0", ignition "P1" and at maximum power "P2" to obtain a
proper flame stability, then goes into CO
2
edit mode to allow the manual calibration.
The mode (AUTO or MANU) is set in the activation code of the parameter "P14" in the TSP Parameters menu as described in the paragraph
“3.2.15. TSP parameters to be set on the interface and using the Remote Control” page 39.
The AUTO mode is the recommended one, since it allows greater freedom in calibrating the CO
2
.
OPERATIONS TO BE PERFORMED
Access the chimney sweep function (see paragraph 3.2.7) and check if the value of CO
2
is within the limits of Table 12, both as regards
maximum (Hi) and lowest (Lo) power (if the temperature of the system rises excessively, open the ACS valve to dissipate heat; the proce-
dure cannot be started with the ACS open).
Otherwise, proceed as described below.
Press simultaneously for the cycle time, the keys "
" and "
" (
A
+
B
fig. 1). Release and then press immediately (within 2 seconds) once
the key “
” (
C
The board confirms activation of the function and shows on the display "
Au-to
" or "
Ma-nu
" depending on the setting mode defined.
The adapter generates internally a "calibration” operation mode request and initialises the start-up sequence. In case the "Au-to” function
is enabled, the symbol "radiator” comes on and flashes.
Once the start-up is done, the boiler performs a parameters programming cycle at maximum power, then at the ignition power, and, finally,
at the minimum power. During this phase the LCD screen displays, alternatively, the cycle time and the delivery circuit temperature.
At this point the user can enter the fumes analysing probe in the exhaust duct.
SELF-ADJUSTMENT
The display shows "P0" and the board is ready to adjust the OR
2
value at minimum power.
Under this condition:
"
" (
D
fig. 1) is used to switch between the Power / O
2
menu (for the cycle time).
"
" or "
" (
F
or
E
fig. 1) are used to increase / decrease the O
2
value or to change the system power (if the related symbol flashes).
