BoilerFaultCodesYour boiler’s internal computer has been set up with the wrong configuration details and cannot operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Wrong card parameter setting
What causes this fault?
This fault occurs when the boiler’s main control board is programmed with the wrong software settings or doesn't recognise the specific model it is installed in. It is most commonly caused by a memory error on the circuit board or because a replacement part was installed without being correctly configured for your specific boiler version.
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 F04 — 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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