BoilerFaultCodesYour boiler's internal computer has encountered a memory or software error and can no longer control the heating properly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Internal fault
What causes this fault?
This fault occurs when the boiler's control center suffers a critical failure in its internal memory or software processing. It is essentially a terminal logic error where the circuit board can no longer safely calculate how much gas or heat to provide. The most common reason is age-related degradation of the electronic components, which causes them to lose their pre-programmed settings.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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