BoilerFaultCodesYour boiler has shut itself down as a safety precaution because it has detected an internal fault that could lead to overheating or unsafe operation.
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 sensors detect that the water temperature has exceeded safe limits or that a critical component has failed. It is usually triggered by a circulation issue within the unit or a faulty sensor sending incorrect data to the control board. For safety, the system shuts down completely to prevent thermal damage to the heat exchanger.
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 E19 — 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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