BoilerFaultCodesYour boiler's internal configuration chip has been disconnected or is not being recognised correctly by the control board.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Code plug number
What causes this fault?
This fault occurs when the boiler's control board loses communication with a small memory chip called a code plug, which tells the boiler how to operate. The most common reason is a loose connection caused by general vibration over time or a hardware failure within the chip or the main circuit board itself.
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.b — 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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