Installation and operating instruction
Oil condensing boiler WTC-OB 18-B
3 Product description
83311002 1/2018-03 La
13-132
3.3.5 Program sequence
Oil preheating
At heat demand
1
, the heat exchanger
2
heats the oil in the nozzle assembly. The
display shows an
H
. When a temperature of approx. 45 °C is reached, the temper-
ature switch
3
closes.
Pre-purge
The fan
4
starts and runs to the pre-purge speed.
Ignition
The ignition
5
and the pump motor
6
are switched on.
Stage 1
7
and stage 2
8
solenoid valves open (burner starts with stage 2).
A flame
9
is formed. Oil preheating
2
is switched off.
Flame stabilisation
Ignition is switched off once the safety time and post-ignition phase
0
has
elapsed. The flame stabilisation time
q
follows.
Operation
The burner is in operation. The flame sensor monitors the flame. The boiler elec-
tronics active the solenoid valve for stage 2
8
depending on heat demand.
Post-purge
If there is no longer a heat demand, the solenoid valves close and stop the fuel
supply. Following the post-purge phase
w
the fan switches off.
1
0
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
q
w
w
0
9
i10