Buderus Logano G234X Installation And Service Instructions Manual page 30

9
Boiler inspection and maintenance
START
PHASE 1
Ignition attempt
PHASE 2
Main burner
operating
END
Fig. 38 Troubleshooting the G234X
30
Room thermostat (control) signals heat requirement
Vent damper (if installed) opens.
Ignition spark generator operates
• ignition gas valve opens.
Ignition burner operation
Ignition flame burns, automatic
ignition signals steady ignition
flame.
Pilot flame stand by
• ignition spark generator stops.
• main gas solenoid valve opens.
Main burner operation
• pilot assembly monitors ignition flame.
Specified thermostat value (control) reached
Main and ignition gas valves close, gas burners ex-
tinguished, vent damper (if installed) closes.
or ignition flame does not burn,
pilot assembly starts ignition at-
tempt, switches off after 90
seconds.
Power interruption
System switches off. Does
the system restart when
power is restored?
Pilot flame fault
Main gas valve closes,
ignition module starts
ignition attempt.
Logano G234X – 6 720 811 233 (2014/05)
6 720 804 440-53.2T