BoilerFaultCodesTechnical description
Flow and return sensor anomaly detected. The sensor shows an incorrect temperature value.
What causes this fault?
This fault occurs when the boiler's control board receives conflicting information from the two probes that monitor water temperature. It happens because one of the sensors has likely degraded and is sending an inaccurate electrical signal, making the boiler think the internal heat levels are unsafe. The system shuts down as a precaution because it can no longer accurately track how much heat is being transferred into your radiators.
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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