BoilerFaultCodesYour boiler is struggling to accurately measure water temperature because its sensors are sending conflicting or incorrect signals.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow and/or return sensor fault
What causes this fault?
This fault occurs when the sensors that monitor the water temperature leaving and returning to your boiler provide inconsistent or impossible readings. The most common reason is that one of these sensors has physically degraded or failed over time, preventing the boiler from safely knowing how hot the water actually is. In some cases, it can also be triggered by a fault in the internal wiring that connects these sensors to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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