BoilerFaultCodesYour boiler's internal computer has encountered a communication error or hardware failure and cannot operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Electronic fault | Electronics defect
What causes this fault?
This fault occurs when the boiler's main control board fails to verify the flame signal or encounters an internal processing error. It is essentially a communication breakdown between the electronic 'brain' and the ignition system, often caused by worn-out components or moisture damage on the 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 F.67 — no call-out fees, no surprises.
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Vaillant Thermocompact 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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