BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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