BoilerFaultCodesYour boiler's internal computer chip has been disconnected or has developed a communication fault, meaning the system doesn't know which settings to use.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler coding card fault
What causes this fault?
This fault occurs when the boiler's main control board loses communication with the small plug-in memory chip that stores the unit's identity and settings. The most common reason is that the chip has vibrated loose, suffered from a hardware failure, or the main circuit board itself can no longer read the data due to a technical glitch.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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