Logano G334X Installation And Service Instructions Manual - page 34
9
Boiler inspection and maintenance
Logano G334X – 6 720 811 237 (2014/05)
34
Fig. 47 Troubleshooting the G334X
START
Room thermostat (control) signals heat requirement
Vent damper (if installed) opens.
Ignition spark generator operates
• ignition gas valve opens.
With steady pilot flame
• ignition spark generator stops.
• main gas solenoid valve opens.
Main burner operation
• automatic ignition monitors pilot flame.
Specified thermostat value (control) reached
Main and ignition gas valves close, gas burners
extinguished, vent damper (if installed) closes.
Ignition burner operation
Pilot flame burns, automatic
ignition signals steady ignition
flame.
or
Pilot flame does not burn,
automatic ignition starts ignition
attempt,
switches off after 90 seconds.
END
PHASE 1
Ignition attempt
PHASE 2
Main burner
operating
Power interruption
System switches off. Does
the system restart when
power is restored?
Pilot flame fault
Main gas valve closes,
automatic ignition starts
ignition attempt.