BoilerFaultCodesYour boiler's electronic control board has detected a communication problem or a mismatch with its internal sensors, causing the system to stop working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Boiler Control Assembly (Use with ‘Ranco’sensor only)
What causes this fault?
This fault occurs when the boiler's main control board loses its ability to accurately communicate with the internal temperature sensors. It is usually caused by the electronic board failing to recognize the specific signals from the sensor, leading the system to shut down as a safety precaution. In many cases, this is due to the control board's internal components wearing out or the sensor itself providing an incompatible reading.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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