BoilerFaultCodesYour boiler has lost its ability to monitor the temperature of the water returning to the system, causing it to stop working 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 fault
What causes this fault?
This fault occurs when the internal sensor responsible for tracking the temperature of water entering the boiler fails to send a reliable signal. The most common reason is that the sensor has physically degraded over time or developed an electrical short, though loose or damaged wiring connections can also prevent the control board from reading the temperature accurately.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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