PART III: OPERATION
28
13 If necessary, adjust the combustion head position (see the dedicated paragraph)..
14 The air and gas rate are now adjusted at the maximum power stage, go on with the point to point adjustement on the
SV1
(gas
side) adjusting cam as to reach the minimum output point.
15 as for the point-to-point regulation, move the gas low flame microswitch a little lower than the maximum position (90°);
16 set the
TAB
thermostat to the minimum in order that the actuator moves progressively towards the low flame position;
17 move the gas low flame microswitch to the minimum to move the actuator towards the low flame until the two bearings find the
adjusting screw that refers to the lower position: screw
V1
to increase the rate, unscrew to decrease.
18 Move again the gas low flame microswitch towards the minimum to meet the next screw on the adjusting cam and repeat the pre-
vious step; go on this way as to reach the desired low flame point.
19 Now adjust the pressure switches.
Fully-modulating burners
.To adjust the fully-modulating burners, use the
CMF
switch on the burner control panel (see next picture), instead of the
TAB
thermo-
stat as described on the previous paragraphs about the progressive burners. Go on adjusting the burner as described before, paying
attention to use the CMF switch intead of
TAB
.
The
CMF
position sets the oprating stages: to drive the burner to the high-flame stage, set CMF=1; to drive it to the low-flame stage, set
CMF=2.
Attention! if it is necessary to change the head position, repeat the air and gas adjustments described above.
CMF = 0 stop at the current position
CMF = 1 high flame operation
CMF = 2 low flame operation
CMF = 3 automatic operation
VRA
RA
TR
TTENZIONE
SV1
SV2
V1
Gas throttle valve open
Gas throttle valve clo-
sed
CMF
R