9. FAULT FINDING
ELECTRICITY SAFETY - Before making any electrical checks, switch off mains supply to boiler.
FAULT POSSIBLE
CAUSE
ACTION
BURNER WILL NOT START
Control box locked out
Press reset button on front of burner.
N.B. ONLY TRY TWICE
Limit-stat tripped
Press reset button under control panel and
check function of boiler control thermostat.
Boiler thermostat or other system
controls satisfied
Ensure all controls are calling for heat.
Fuse blown
Fit new 5 amp fuse, if it blows again, check
for short circuit in wiring.
Check for live supply continuity up
If live supply confirmed, change control box
to burner
Motor or pump seized
Check for rotation and replace as
necessary.
BURNER STARTS
No oil supply
Check oil level in tank and feed to burner.
BUT FLAME NOT
ESTABLISHED
Photo-cell not seeing flame
Clean photo-cell and ensure it is fully
plugged in.
Air trapped in pump
Bleed off air through pressure gauge
tapping.
Solenoid valve faulty
Check coil for continuity and
replace if faulty.
Nozzle blocked
Replace nozzle with one of same
specification.
Electrodes incorrectly set
Reset gap and position
electrodes as shown in Burner diagram.
Electrode insulator cracked
Check and replace if insulator cracked or
crazed.
Ignition transformer and H.T.
contacts
Check for spark and condition of H.T.
contacts. Replace as necessary.
Low oil pressure
Check pump pressure and adjust to
correct setting.
FLAME ESTABLISHED
Oil contaminated with water
Run off oil at burner until free of
BUT BURNER LOCKS
water and drain condensation from tank
OUT AFTER FEW SECONDS
Oil filter partially blocked
Wash filter clean with kerosene.
Photo-cell fault
Clean photo-cell and ensure
it is fully plugged in. Replace if faulty.
Oil pressure low
Check pump pressure and adjust
to correct setting.
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