BoilerFaultCodesYour boiler's internal computer has lost its identity because the memory chip is either loose or failing.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 8.A — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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