BoilerFaultCodesYour boiler's computer brain has developed a serious internal fault or a loose connection, preventing it from starting the burner safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: The burner control unit is faulty – check the plug and wiring of the burner control unit.
What causes this fault?
This fault occurs when the boiler's internal computer can no longer communicate reliably with the components that manage the gas flame. The most common reason is an electrical failure within the control board's circuitry or a communication break caused by a loose or damaged wiring connection. Because the boiler cannot guarantee it can control the fire safely, it shuts down entirely as a protective measure.
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 EH258 — no call-out fees, no surprises.
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Worcester Bosch GB162 is discontinued — time for a new one?
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