BoilerFaultCodesTechnical description
Return sensor error – sensor may be wet or damaged
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 developed an electrical failure due to age or has been damaged by a small internal leak making the components wet. Without accurate temperature readings, the boiler shuts down to prevent it from overheating or operating inefficiently.
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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