50
ROTEX GCU compact -
10
x
Faults and malfunctions
1) See documentation "ROTEX RoCon BF Controller"
Tab. 10-1 Possible faults on the GCU compact
Burner fan not run-
ning despite burner
demand
No mains voltage on burner
Ɣ
Insert X1 plug on automatic firing until it clicks in place.
Ɣ
Check voltage at the terminals L-N of the X1 plug
Ɣ
Check/ renew fuse.
Plug connections switching panel PCB or auto-
matic firing are loose
Ɣ
Check/ insert plug connections
Burner blower defective (bearing has seized)
Ɣ
Replace the burner blower.
No gas pressure
Ɣ
Inspect the gas connections.
Air in the gas line
Ɣ
Vent the gas line.
Gas control block does not open
Ɣ
Check the plug connections between the safety gas
control block and firing unit and insert correctly.
Ɣ
Check the safety gas control block (zero pressure
during the ignition).
Ɣ
Replace the safety gas control block.
Ɣ
Replace the combustion controller.
No ignition
Ɣ
See fault "No ignition".
Burner starting is hard Start delay due to bad ignition
Ɣ
Adjust ignition electrodes
Ɣ
Check the starting output and adjust as necessary.
No ignition
Ignition electrodes short circuited
Ɣ
Check the ignition electrodes, adjust or replace as
necessary.
Distance of ignition electrodes too large
Ɣ
Check the ignition electrodes and adjust where
necessary.
ignition electrodes contaminated or humid
Ɣ
Clean the ignition electrodes and check the burner
settings.
Ignition electrodes burnt out
Ɣ
Change ignition electrodes
Insulating body cracked
Ɣ
Change ignition electrodes
Ignition transformer defective
Ɣ
Replace ignition transformer
Ignition cable defective, arking
Ɣ
Change ignition cable and determine the cause
Firing unit faulty
Ɣ
Replace the combustion controller.
Loud operating noises Wrong burner setting
Ɣ
Re-adjust the burner setting.
Bearing damage on burner fan
Ɣ
See fault "Loud, whistling mechanical noise".
Loud, whistling
mechanical noise
Burner blower bearing defective
Ɣ
Replace the burner blower.
STL switch off
Water throughput too low due to air inclusion
Ɣ
Vent system
Water flow too low due to valves closing too
quickly along the entire heating network
Ɣ
Use slow closing or timed valves, if needed, install
overflow valve
Pump standstill
Ɣ
Check mains and PWM control signal connection,
replace pump if necessary.
Malfunction
Possible cause
Possible solution
