BoilerFaultCodesYour boiler is not broken; it has simply been put into a manual testing mode and needs to be switched back to its normal setting.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Not a fault code. Service mode selected to min, press service button to return to normal.
What causes this fault?
This occurs because the boiler has been manually toggled into a low-power service mode, usually by someone accidentally pressing the service button on the control panel. This mode is designed for engineers to test emissions at minimum output, so the boiler is simply following a command rather than reacting to a mechanical failure. To fix it, you just need to press the service button again to return the system to its normal heating settings.
DIY fix possible
Locate the button with a 'spanner' or 'service' icon on the control panel.Press the service button once briefly.The blue light should stop pulsing and return to a steady state, indicating normal operation.
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 Blue light: 2 pulses, Lockout reset button: No light — 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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