BoilerFaultCodesYour boiler has stopped working because the internal computer and its sensors are no longer communicating correctly with each other.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control/sensor failure
What causes this fault?
This fault occurs when the boiler's main control board loses the ability to accurately read data from its internal temperature sensors. It is usually caused by a physical failure within the circuit board itself or damaged wiring that prevents electrical signals from reaching the central processor.
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 A18 — no call-out fees, no surprises.
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