BoilerFaultCodesYour boiler's internal computer has developed an electronic fault and is unable to communicate with its sensors.
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 (PCB)
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure and can no longer process signals from the safety sensors. It is usually caused by electrical components on the circuit board wearing out over time or being damaged by a sudden power surge. Because the 'brain' of the boiler can no longer guarantee safe operation, it shuts the system down entirely.
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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