BoilerFaultCodesYour boiler's main internal computer has developed a communication or hardware error and cannot manage the heating process safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main PCB fault
What causes this fault?
This fault occurs when the boiler's central control board suffers an internal hardware failure or loses the ability to communicate with its sensors. The most common reason is age-related wear on the electronic components or a sudden electrical surge that has damaged the delicate circuitry.
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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A boiler cover plan would cover faults like F64 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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