BoilerFaultCodesYour boiler has stopped working because it cannot communicate with the internal sensor that monitors your hot water temperature.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: S3 sensor open circuit
What causes this fault?
This fault occurs when the boiler's main control board loses its connection to the sensor that measures hot water temperature. The most common reason is that the sensor itself has developed an internal electrical failure or the wiring connecting it to the system has come loose. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
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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