BoilerFaultCodesYour boiler is temporarily struggling to talk to its internal control parts and is trying to reconnect itself.
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: Communication error between printed circuit board (PCB) and Control – this is a temporary error, the system should reset on its own
What causes this fault?
This fault occurs when the boiler's main control board loses its digital connection with the internal display or user interface components. It is often caused by a brief dip in power or electrical interference that prevents these parts from sharing data correctly. In most cases, it is a hardware 'stutter' rather than a permanent mechanical breakage.
DIY fix possible
Wait up to 10 minutes to see if the error clears itself as designedTurn the selector switch to 'Reset' for 5 seconds and then back to its original positionSwitch the main electrical power to the boiler off and back on again
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 4 Green Flashes — no call-out fees, no surprises.
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