BoilerFaultCodesYour boiler has stopped working because its internal control computer has lost its configuration settings or is unable to communicate with its safety sensors.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: No monitoring
What causes this fault?
This fault occurs when the boiler's main control unit loses the specific digital 'identity' required to operate your heating system safely. It is typically caused by a corrupted coding chip or a breakdown in communication between the central computer and the internal sensors. Without these settings, the boiler shuts down as a safety precaution because it no longer knows its own technical parameters.
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 9C:0 — 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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