50
Installation and Servicing
Section 4 - Fault Finding
FAUL
T FINDING
4.4 ‘L 06’ - FLAME ON BEFORE GAS VALVE ON
4.5 ‘F 01’ - LOW WATER PRESSURE
Are the Boiler and CH System filled with water and all isolation and
radiator valves open (check pressure gauge is between 1 to 1.5 bar)?
NO
NO
YES
Fill and vent the system and open all
isolation valves
YES
Are connections on water pressure switch secure?
Re-fit connections
Replace water pressure switch
4.6 ‘F 02 OR FN OR LN’ - FLAME LOSS
Does the boiler ignite for a short
time and then extinguish?
YES
Is the Gas Pressure available at
the Boiler Inlet (>18 mbar)?
Check the electrode and associated
harness for: continuity, visual
condition and position
Check if condensate pipe is
blocked. Check if flue is blocked.
Replace as necessary
NO
Check gas supply and
rectify fault
NO
YES
Is 24Vdc supply available at the
Gas Valve while the flame is on?
YES
Check spark generator and associated
harness for: continuity and visual
condition.
Are these functioning correctly?
YES
Check electrode and associated
harness for: continuity, visual condition
and position.
Are these functioning correctly?
YES
Check trap and condensate drain
pipe work for blockage and rectify
if necessary. Boiler now working
OK?
Check wiring from
gas valve to PCB for
continuity. If the wiring
is OK then replace the
PCB
NO
Replace Spark
Generator and Harness
as necessary.
NO
Replace electrode and
associated harness as
necessary
NO
Replace Gas Valve
NO
Refer to Section
3.9
Refer to Section
3.9
Refer to Section
3.14
Restart the boiler, does Boiler Work OK?
NO
Check routing and integrity of internal boiler wiring is OK.
Check condition of Electrode and replace if deteriorated.
YES
Replace Electrode