DBW 160/230/300/350
Control
81
11
Control
Bild 40: Functional diagram with control unit 1553
(regular sequence of operation)
(1) Switching on
(2) Initial cycle 10...25 s
(3) Start
(4) Safety delay time 5 ... 25 s
(5) Operation (safety delay time inter
rupts)
(6) control pause starts
(7) Purge cycle ~150 s
(8) control pause ends
(9) Switching off
(10) Heater stops
A
Operation indicator light
B
Circulating pump,
negative for heater
C
heater motor
D
Electronic ignition unit
E
Solenoid valve
F
Flame sensor
G
Control thermostat
It is possible during the purge cycle swit-
ching on again the heater.
Functional diagram with control unit 1553