BoilerFaultCodesYour boiler's internal computer has suffered a critical failure and can no longer control the heating system safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Contact Installer
What causes this fault?
This fault occurs when the boiler's main control board suffers an electrical failure, preventing it from processing instructions or monitoring safety sensors. The most common reasons are internal component wear, moisture ingress, or an electrical surge that has damaged the delicate circuitry on the board.
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 PCB Fault — 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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