BoilerFaultCodesYour boiler's internal computer has encountered a communication error or a serious hardware failure that prevents it from running 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 loses the ability to properly communicate with the gas valve. The most common reason is a physical failure of the internal circuitry on the printed circuit board or a short circuit in the wiring connecting these two vital components. Because the computer can no longer safely control the flow of gas, it shuts the system down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.61 — no call-out fees, no surprises.
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