Buderus Logano GE434 Maintenance Instructions Manual page 58

11 Troubleshooting
Operating condition/faults observed
Initial start-up:
Burner starts, gas valve click audible.
Afterwards no further reaction discernible.
Control device indicates no fault.
After commissioning:
Burner starts, gas valve click audible.
Afterwards no further reaction discernible.
Control device indicates no fault.
Burner starts but goes into a fault state
approx. 3 minutes after the second start.
Fault display on the control device.
No ignition spark recognised.
Burner starts but goes into a fault state
approx. 3 minutes after the second start.
Fault display on the control device.
No or only a very small pilot flame is
recognisable.
Burner starts but goes into a fault state
approx. 3 minutes after the second start.
Fault display on the control device.
A perfect pilot flame is recognisable.
No ionisation current can be measured.
Burner starts but goes into a fault state
approx. 3 minutes after the second start.
Fault display on the control device. A
perfect pilot flame is recognisable.
Ionisation current
< 1.5 µA.
Main flame does not burn.
Pilot flame burns constantly, but no fault.
We reserve the right to make any changes due to technical modifications.
Commissioning and maintenance instructions Logano GE434 Gas-fired special boiler • Issue 02/2003
58
Troubleshooting
Info: The burner control unit detects
insufficient gas pressure.
Gas governor installed acc. to
instructions?
Gas governor adjusted to the correct
value?
Correct sequence observed during the
gas type conversion?
Info: The burner control unit detects
insufficient gas pressure.
Natural gas supply pressure >10 mbar?
LPG supply pressure
> 25 mbar or 15 mbar
Gas governor adjusted acc. to
instructions?
Ignition spark audible with ignition cable
pulled off?
Gas supply pipe purged?
Pilot gas nozzle contaminated?
Burner warm – pilot flame OK and cold
burner – no pilot flame?
Can you hear the pilot gas valve's opening
click?
N and L leads interchanged?
Voltage between L and PE?
No proper ionisation lead contact?
Ionisation electrode short to earth?
Burner control unit faulty?
Ionisation electrode wire or ceramics
contaminated?
Wiring not in accordance with wiring
diagram?
Gas solenoid valve or burner control unit
faulty?
Contact not OK (loose contact)?
Remedy
Remedy the installation fault.
Does the gas pressure < comply with the
stated values; determine the fault in the
gas supply.
Pressure OK – check and, correct the gas
governor settings, if required.
If not: Replace intermittent ignition.
If yes: Replace ignition electrode or pilot
burner.
Purge until gas is flammable.
Blow out pilot gas pipe and nozzle.
If yes: Replace intermittent ignition.
If not: Check wiring and plug contacts.
Remedy the fault.
If not: Earth PE and install isolating
transformer, if necessary.
Remedy fault and replace faulty part, if
required.
Clean the electrode or, if necessary,
replace the pilot burner.
Correct wiring in accordance with the
wiring diagram.
Check the gas solenoid valve or burner
control unit, and replace faulty parts, if
required.
Check contacts and renew, if required.
Buderus Heiztechnik GmbH • http://www.heiztechnik.buderus.de