Your boiler is repeatedly shutting down and trying to restart itself, likely due to an underlying component failure preventing reliable ignition.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Restart occurs 5 times within 15 minutes.
What causes this fault?
This fault occurs when the boiler senses a repeated failure to maintain a steady flame, causing it to shut down and attempt to restart itself five times in a short period. The most common reason is that the internal sensors or gas components are struggling to confirm a safe ignition, eventually leading the system to lock itself out for safety.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like L 0C — 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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