BoilerFaultCodesYour boiler's main internal computer has developed a serious glitch or hardware failure, meaning the unit cannot safely manage its functions.
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 central control hub suffers an internal electrical failure or loses communication with its sensors. The most common reasons include a power surge that has damaged the delicate circuitry or moisture getting into the casing and causing a short circuit.
This fault is slightly more common in winter when the boiler is under high demand and components are subjected to more thermal stress and vibrations.
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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