BoilerFaultCodesYour boiler has shut itself down as a safety precaution because one of its internal safety sensors has detected a potential 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 switches detect that the unit is operating outside of safe temperature or pressure limits, triggering an immediate shutdown to prevent damage. The most common reason is a failure in the safety thermostat or the flue sensor, which may be sending incorrect signals to the control board. It can also be caused by a communication error within the internal wiring or the main circuit board itself.
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 E24 — 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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