BoilerFaultCodesYour boiler has shut itself down for safety because a central control unit or an internal monitoring device has detected a serious fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The safety devices have been activated (lockout)
What causes this fault?
This fault occurs when the boiler's internal safety checks detect a major communication failure or a critical error within the electronic control system. It is usually triggered when the main circuit board can no longer safely manage the heating process, causing the unit to shut down instantly to prevent damage. The most common reasons are a malfunctioning main PCB or a fault in the wiring harness that connects the boiler's various sensors.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like E15 — 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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