BoilerFaultCodesYour boiler has shut itself down as a safety precaution because it has detected an internal fault that needs professional attention.
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 software detects an inconsistency during the ignition or combustion process and shuts down to prevent damage. The most common cause is a failure of the main circuit board to communicate correctly with the gas valve or ignition system. It can also be triggered by electrical interference or a component failing to provide the correct feedback during startup.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like E22 — 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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