BoilerFaultCodesYour boiler has experienced a nervous breakdown in its main computer brain, which means it cannot communicate with itself and has stopped working for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: internal failure - electronic
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure, preventing it from processing instructions or identifying its own components. The most common reason is age-related wear on the delicate electrical circuits or a sudden power surge that has damaged the board's memory.
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 442 — no call-out fees, no surprises.
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