BoilerFaultCodesYour boiler is in a standby or programming mode and thinks it has been told to stay switched off.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: PCB Programming - Off state
What causes this fault?
This fault occurs when the boiler's internal computer has been set to a software-off state, often following a power cut or a manual adjustment in the programming menu. Instead of a mechanical breakdown, the boiler has essentially 'forgotten' it should be running and is stuck in a standby mode. In some cases, this can also happen if the main circuit board has a glitch and requires a professional reconfiguration.
DIY fix possible
Check that the boiler mode dial is turned to 'on' or the 'Hot Water and Heating' positionPress and hold the 'Reset' button for three secondsTurn the power to the boiler off at the fused spur switch, wait 30 seconds, and turn it back on
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