BoilerFaultCodesWhat the manual says
Manufacturer manualCommunication 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
Avoid the next call-out bill
A cover plan would handle faults like 4 Green Flashes: no call-out fees, no surprise bills.
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