34
Bentone
8.2 List of components
A1 Oil burner control
B1 Flame detector
F1 Fuse
H1 Lamp, low capacity
H2 Lamp, high capacity
H3 Lamp, lock-out signal 230 V
M1 Burner motor
M2 Damper motor
SQN75.244A21B
P1 Time meter, low capacity
(optional)
P2 Time meter, high capacity
(optional)
S1 Operating switch
S2 Operating switch, high/low
capacity
S3 Control thermostat
S4 Temperature limiter
S5 Micro switch for hinged door
S6 Control thermostat, high/low
S7 Main switch
T1 Ignition transformer
X1 Connection terminal board
X2 Earth terminal
X3 Plug-in contact, burner
X4 Plug-in contact, boiler
X5 Plug-in contact
high/low capacity burner
X6 Plug-in contact
high/low capacity boiler
Y1 Solenoid valve 1
Y2 Solenoid valve 2
If S6 is missing connection between
T6 and T8. Mains connection
and fuse in accordance with local
regulations
Control of photo current
The current through photo unit is
measured with a d.c. ammeter (a
moving coil instrument connected in
series with the photo unit).
8.2.1 Function
1
1. Switch on operating switch and twin thermostat
The burner motor starts, an ignition spark is formed, the prepurge
goes on till the prepurge period expires and the solenoid valve 1
opens (2)
2.
Solenoid valve 1 opens
Oil mist is formed and ignited. The photocell indicates a flame.
3.
a
b
The safety time expires
If no flame is established before this time limit the control cuts out.
If for some reasons the flame disappears after this time limit, the
burner will make an attempt to re-start.
4
Full load thermostat ON
1) The ignition spark goes out 15 s. after flame indication
(LOA24.171...). (2) The ignition spark goes out 2 s. after flame
indication.when the ignition transformer is connected to terminal
7 (LOA24.173...). The burner is in operating position and can now
change between high and low capacity.
4-5
Operating position
If the burner operation is interrupted by means of the main switch
or the thermostat, a new start takes place when the conditions in
accordance with point 1 are fulfilled.
The oil burner control cuts out
A red lamp in the control is lit. Press the reset button and the
burner re-starts.
Post-ignition
(2) If a post-ignition of 15 s is wanted, move the ignition transformer
from terminal 7 to terminal 6 (LOA24.173...).
Technical data oil burner control
LOA
Pre-ignition time:
13 s
Pre-purge time:
13 s
(1) Post-ignition time:
15 s
(2) Post-ignition time:
2 s
Safety lock-out time:
10 s
Reset time after lockout:
≈ 50 s
Reaction time on flame failure:
< 1 s
Ambient temperature:
-20 - +60°C
Min. current with flame established:
65 µA
Max. photo current at start:
5 µA
