BoilerFaultCodesYour boiler has shut down completely because a safety sensor has detected an internal issue and locked the system for protection.
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 water temperature has exceeded safe operating limits. The most common cause is a lack of water circulation, often due to a failing pump or a blockage within the heat exchanger. Because the heat cannot be moved away from the burner quickly enough, the system shuts down to prevent permanent damage to the components.
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 E06 — 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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