BoilerFaultCodesYour boiler has tried and failed to start up five times in a short window and has now locked itself out for safety.
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 your boiler detects that it has lost its flame five times within a fifteen-minute window, forcing it to stop running to ensure your safety. The root cause is usually a failure in the ignition process, meaning the boiler can't reliably light the gas or recognize that a flame is present. This is often caused by a worn-out ignition spark, a faulty sensor, or an inconsistent flow of gas to the burner.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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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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