BoilerFaultCodesYour boiler has shut down completely for safety reasons because it failed to light a flame.
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 attempts to start but is unable to detect a steady flame, causing it to shut down for safety. The most common reasons include a lack of gas supply to the unit, a build-up of carbon on the ignition probe, or a component failure that prevents the spark from firing.
This fault is more common during extreme cold spells, as external gas regulators or pipes can sometimes freeze, restricting the gas flow required for ignition.
DIY fix possible
Check that your gas prepayment meter has credit (if applicable)Ensure the gas stop tap is fully openPress the reset button once to see if the boiler restarts
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E01 — 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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