BoilerFaultCodesYour boiler has stopped running and entered a safety shutdown mode, which is indicated by the reset button flashing.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Blue light Lockout reset button
What causes this fault?
This fault occurs when the boiler's control system detects a failure in the ignition process or a loss of flame signal during operation. The most common reasons are that the burner has failed to light correctly or the internal sensors can no longer verify that a flame is present for safety. This results in the boiler shutting down immediately to prevent unburnt gas from building up in the system.
DIY fix possible
Press and hold the flashing Reset button for five seconds.Wait for the blue light to stop flashing and stay on constant.Ensure your gas supply is active and your system pressure is between 1 and 1.5 bar.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like Volatile lockout — no call-out fees, no surprises.
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Worcester Bosch Greenstar 12i System is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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