BoilerFaultCodesYour boiler has detected an internal electronic error that suggests the main control unit is beginning to fail, which may cause your heating and hot water to become unreliable.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: 2x daily
What causes this fault?
This fault occurs when the boiler's internal computer brain fails to perform its routine self-checks correctly. It is typically caused by aging electronic components on the circuit board that can no longer communicate reliably with the rest of the system. While the boiler may occasionally clear the error on its own, it usually indicates that the hardware is worn out and needs professional attention.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like 63:15 — 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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