C.I.B. UNIGAS - M039132CD
33
rotating the round plate
C
by means of the screw
V3
(turn clockwise to decrease the gas rate or counterclockwise to increase it). The
index
S
shows the opening angle of the butterfly valve
.
Note:
If it should be necessary to adjust the rating of the burner in low flame operation, once all the adjustments are accomplished, act
on the related cam of the actuator (see next paragraph). Then, check the gas rate and, eventually, repeat step 11.
z
progressive or fully-modulating burners
13 still in the high flame operation and with the actuator on its 90° position, find the
V
screw on the adjusting cam
SV
(see next pic-
ture), matching with the bearings that move along the foil and related to the servocontrol position.
14 unscrew the
V
srew to increase the air folw rate, unscrew to decrease it
15 once the maximum flow rate is fixed, shortcircuit for a while, the thermostat
TAB
T6 and T7 terminals (see pag. 45). As far as the
fully-modulating models, see next paragraph. The actuator will move towards the low flame position; then remove the bridge;
16 then adjust the screw
V
related to that position;
17 shortcircuit, again for a while, the
TAB
T6 and T7 terminals and repeat from point 5;
18 repeat all these instructions for all the actuator stroke, in order to define the foil shape.
Note:
If it should be necessary to adjust the rating of the burner in low flame, work on the corresponding cam of the actuator. After this
operation, check the gas rate and verify the combustion values. In case of lack or excess of air, work on the screws
V
of the adjusting
cam (see next picture) matching the setting point of the air rate in low flame; unscrew to increase the air rate or screw to decrease it.
Fully modulating burners
To adjust the air rate in low flame and in the intermediate points, proceed as follow.
1
Keep pushed for 5 seconds the EXIT button on the modulator (Fig. 102); when the LED with the hand symbol lights up, push the
arrow button, driving the actuator to the maximum opening position progressively;
2
stop its stroke when it meets each screw
V
: adjust the air rate by adjusting the
V
screw that matches each bearing.
3
Push the EXIT button to quit the manual mode.
Gas Proving System VPS504 (Option)
The VPS504 check the operation of the seal of the gas shut off valves. This check, carried out as soon as the boiler thermostat gives a
start signal to the burner, creates, by means of the diaphragm pump inside it, a pressure in the test space of 20 mbar higher than the
supply pressure.
To install the DUNGS VPS504 gas proving system on the MD-DLE valves group, proceed as follows:
1
turn off gas supply.;
2
Switch off power supply.
3
remove the Multibloc’s screw plugs (Fig. 94-A);
4
iInsert sealing rings (10,5 x 2,25) into VPS 504 (Fig. 96-B, Fig. 94-B)
5
Torque screws 3, 4, 5, 6 (M4 x16) Fig. 94-C
Only use screws with metric thread on reassembly (modification, repair).
6
On completion of work, perform a leak and functional test.
DOUBLE-STAGE-PROGRESSIVE-FULLY-MODULATING
MIN
MAX
VRA
RA
V2
V1
V3
C
V
SC
SV
Summary of Contents for IDEA NG280
Page 45: ...C I B UNIGAS M039132CD 45...
