BoilerFaultCodesYour boiler has detected a problem with one of its internal temperature sensors, which means it cannot safely measure how hot the water is and has stopped working as a precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Sensor fault S2
What causes this fault?
This fault occurs when the boiler's control system loses a reliable signal from the return temperature sensor. The most common cause is a failure of the internal thermistor component, but it can also be triggered by loose or corroded electrical connections between the sensor and 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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Could it be time for a new boiler?
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