BoilerFaultCodesWhat the manual says
Manufacturer manualMiscellaneous error
From this model's manual
This code was read directly from the manufacturer service manual for this model.
What causes this fault?
This fault occurs when the boiler's internal computer, the Printed Circuit Board, loses the ability to send or receive messages from other components. It is often caused by a loose connection in the wiring or a hardware failure within the control board itself. Think of it like a computer crash where the system can no longer tell the boiler how to operate safely.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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