Burner lights but locks out
after 5 seconds
Live and neutral inverted
Poor earth
Check electrical connections
Faulty ionisation probe
Check electrical connection on
probe.
Check probe for cracks or
damage.
Replace ionisation probe .
Faulty ignition
Check the gas type is suitable
for the heater.
Check the inlet gas pressure.
Check the head pressure.
Check the gas supply pipes
have been properly purged of
air .
Explosive start up.
Faulty ignition electrode
Replace ignition electrode
Incorrect electrode position
Reposition electrode correctly
over the burner bar.
Faulty burner tube
Replace the burner tube
Faulty ignition transformer
Replace ignition transformer
Faulty ignition
Check the gas type is suitable
for the heater.
Check the inlet gas pressure.
Check the head pressure.
Check the gas supply pipes
have been properly purged of
air .
heat exchanger dirty
Check / clean heat exchanger
Burner shuts down then
re lights automatically .
No indication lights on
.
Pressure differential switch not
operating correctly
Check that air pipe to switch not
damaged or blocked.
Check that the flue and
combustion air pipes are clear.
Check that the thermal overload
on the flue venter has not
operated
Faulty pressure differential
switch
Replace differential switch
Room thermostat in warm air
flow
Check position of thermostat
