BoilerFaultCodesYour boiler has detected a fault with the sensor that monitors the temperature of the water returning to the unit, causing it to stop the heating system for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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