BoilerFaultCodesYour boiler has switched itself off for safety because it has detected a problem with internal pressure or a safety sensor has been triggered.
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 circuit is broken, usually because the system has lost too much water pressure to operate safely. It can also be triggered if the unit begins to overheat, causing a safety sensor to trip and shut down the burner to prevent damage. The most common reasons are a leak somewhere in the central heating system or a faulty sensor that is incorrectly reporting a problem.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E10 — 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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