C.I.B. UNIGAS
- M039203CC
18
Gas Filter
The gas filters remove the dust particles that are present in the gas, and prevent the elements at risk (e.g.: burners, counters and regu-
lators) from becoming rapidly blocked. The filter is normally installed upstream from all the control and on-off devices.
Adjustments - brief description
Adjust the air and gas flow rates at the maximum output (“high flame”) first, by means of the air damper and the adjusting cam respec-
tively.
z
Check that the combustion parameters are in the suggested limits.
z
Check the flow rate measuring it on the counter or, if it was not possible, verifying the combustion head pressure by means of a dif-
ferential pressure gauge, as described on par. see “Measuring the gas pressure in the combustion head” on page 17.
z
Then, adjust the combustion values corresponding to the points between maximum and minimum: set the shape of the adjusting
cam foil. The adjusting cam sets the air/gas ratio in those points, regulating the opening-closing of the throttle gas valve.
z
Set, now, the low flame output, acting on the low flame microswitch of the actuator in order to avoid the low flame output increasing
too much or that the flues temperature gets too low to cause condensation in the chimney.
Adjustment procedure for gas operation
1
Set GAS fuel by means of the burner
CM
switch (it is placed on the burner control panel - see page 26)
2
Only for burners provided with
Multibloc MB-DLE gas valves:
before starting the burner up, set the slow opening. To set the slow
opening, remove cover
T
, reverse it upside down and use it as a tool to rotate screw
VR
. Clockwise rotation reduces start flow rate,
anticlockwise rotation increases it. Do not use a screwdriver on the screw
VR
!
Note:
the screw
VSB
must be removed only in case of replacement of the coil.
Attention:
z
Beger actuator: cams can be moved manually
z
Siemens actuator: set the MAN/AUTO lever to MAN to move the cams, rememeber to set it to AUTO once the adjustment
is accomplished.
ATTENTION:
before starting the burner up, be sure that the manual cutoff valves are open and check that the pres-
sure upstream the gas train complies the value quoted on paragraph “Technical specifications”. Be sure that the
mains switch is closed.
.
ATTENTION:
During commissioning operations, do not let the burner operate with insufficient air flow (danger of formation
of carbon monoxide); if this should happen, make the gas decrease slowly until the normal combustion values are achieved.
WARNING: NEVER LOOSE THE SEALED SCREWS! OTHERWISE, THE DEVICE WARRANTY WILL BE IMMEDIA-
TELY INVALIDATE!
VPS504 Gas proving system
The VPS504 check the operation of the seal of the gas shut off val-
ves. This check is carried out as soon as the boiler thermostat gives
a start signal to the burner, creating, by means of the diaphragm
pump inside it, a pressure in the test space of 20 mbar higher than
the supply pressure.
When wishing to monitor the test, install a pressure gauge ranged to
that of the pressure supply point PA.
If the test cycle is satisfactory, after a few seconds the consent light
LC (yellow) comes on. In the opposite case the lockout light LB (red)
comes on.
To restart it is necessary to reset the appliance by pressing the illu-
minated pushbutton LB.
Fig. 18
IMPORTANT! the combustion air excess must be adjusted according to the in the following chart:
Recommended combustion parameters
Fuel
Recommended (%) CO
2
Recommended (%) O
2
Natural gas
9 ÷ 10
3 ÷ 4.8
Light oil
11.5 ÷ 13
2.9 ÷ 4.9
LC
LB
PA
