BoilerFaultCodesTechnical description
Return temperature sensor error
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors water coming back from your radiators. The most common reason is that the sensor has electronically failed or developed a loose connection, preventing the boiler from knowing if it is safe to continue heating. Without this data, the system shuts down as a safety precaution to prevent internal overheating.
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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