BoilerFaultCodesYour boiler's internal computer has encountered a critical error and can no longer control the heating or hot water system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty main PCB
What causes this fault?
This fault occurs when the boiler's main control board suffers a hardware failure and can no longer process data or send signals to other components. The most common reason is a short circuit within the board's circuitry or an electrical surge that has damaged the delicate microprocessors. Because the 'brain' of the boiler is compromised, it cannot safely manage the gas burner or water pumps.
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 FE — no call-out fees, no surprises.
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Viessmann Vitodens 100 Compact is discontinued — time for a new one?
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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