40
EN
N° 8530-1GB
Rev. 23/02/00
DIAGRAM OF CONNECTING MORE THAN ONE
BURNER TO THE GAS PIPE NETWORK AT
AVERAGE PRESSURE
1
MEASURING AND REDUCING UNIT
2
INTERCEPTION
3
GAS FILTER
4
PRESSURE REDUCER
5
METER
6
EMERGENCY INTERCEPTION (INSTALLED OUTSIDE)
7
BALL COCK
8
GAS FILTER
9
FINAL REDUCER OR PRESSURE STABILIZER
(ADAPT TO THE SPECIFIC CASE)
10
ANTI-VIBRATION JOINT
11
A COUPLE OF FLANGE
D
DISTANCE BETWEEN PRESSURE STABILIZER AND FLANGES (about 1.5÷2m).
ELECTRICAL CONNECTIONS
The three-phase or single-phase electric supply line of the minimum section in proportion to the power absorbed by
the burner must be equipped with a fused switch. Furthermore, regulations require a switch on the burner’s feed line,
which should be located outside the boiler room in an easily accessible position. All electric lines must be protected by
flexible sheaths, be firmly secured and be laid a long way from high temperature parts. For the electrical connections
(line and thermostat) see the relevant diagram.
DESCRIPTION OF OPERATIONS
By closing the main switch, and if the thermostats are closed, voltage will reach the cyclic relay motor which will then
start operating. The fan motor is then turned on and it will carry out a pre-ventilation of the combustion chamber. At
the same times the motor which controls the combustion air shutter moves the air shutter to the correct open position
for the 2nd flame. Pre-ventilation of the combustion chamber takes place when the air shutter is open at the 2nd flame
position. At the end of the pre-ventilation phase, the combustion air shutter is taken back to the 1st flame position
ignition takes place and, after three seconds, the principle and safety gas valves open and the burner starts up.
We should point out that:
a) The two-stage principle valve is fitted with a device, which regulates gas delivery for the let and 2nd flames (see
specific instructions for the 2-stage valve model fitted to the burner).
b) The safety valve is an ON/OFF version (see specific instructions for valve model fitted to the burner).
Flame presence detected by its own relative control device, permits the continuation and completion of the ignition
phase with the disconnection of the ignition transformer.
Subsequently, the 2nd flame is inserted (there is an increase in combustion air and the principle valve is open at the
2nd stage position). In the case of flame failure, the control box activates a “safety shut down” within three seconds of
the opening at the let flame position of the principle valve. When there is a “safety shut down”, the valves are imme-
diately re-closed. To unblock the control box from the safety position push the luminous button on the control panel.
NOTE - The air shutter is activated by an electric motor (see specific instructions in the following pages). It should be
kept in mind that when the burner comes to a standstill due to the intervention of the thermostats, the air shutter
will be taken back to its completely closed position (energostop) by its electric motor.
Control box or
Safety
Preventilation
Pre-
Post-
Time between opening
Cut out of pilot flame
Time between opening
programmer
time
time
ignition
ignition
of pilot valves and
after opening of
1st flame valve
opening of main valves
main valves
and 2nd flame valve
s
s
s
s
s
s
s
LFL 1.333
3
31,5
6
3
12
3
12
