BoilerFaultCodesYour boiler has stopped working because it cannot communicate with the sensor that monitors water returning from your radiators.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return temperature sensor interruption
What causes this fault?
This fault occurs when the boiler's control board loses the signal from the sensor that measures the temperature of the water coming back from your heating system. The most common reason is that the sensor has developed an internal electrical failure, or the wiring connecting it to the main computer has become loose or damaged. Without this data, the boiler shuts down as a safety precaution because it cannot monitor the efficiency or heat levels of the system.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.01 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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