BoilerFaultCodesTechnical description
Software version CF
What causes this fault?
This fault occurs when the boiler's main control board loses communication with a small memory chip called a code plug, which tells the boiler exactly which model it is. The most common reason is that the chip has vibrated loose over time or its electronic circuits have failed, meaning the boiler can no longer operate safely without knowing its own identity.
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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