BoilerFaultCodesYour boiler's burner has stopped working and has gone into a safety lockout mode.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner fault (possibly burner lockout)
What causes this fault?
This fault occurs when the burner fails to fire up or maintain a flame during operation, prompting the boiler to shut down for safety. The most common reasons include a blockage in the oil nozzle, a dirty light sensor that cannot detect the flame, or a mechanical failure within the fuel pump.
This issue is more frequent during the first cold snap of autumn when sediment in the oil tank is pulled into the system after a period of inactivity.
DIY fix possible
Check that you have enough oil in your storage tankEnsure the oil supply valve is fully openPress the illuminated reset button on the burner once and wait for it to restart
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E5 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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