BoilerFaultCodesYour boiler has stopped working because its internal temperature sensor is reporting an error, meaning it can no longer monitor heat levels safely.
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 S5.
What causes this fault?
This fault occurs when the boiler's internal S5 temperature sensor stops sending a reliable signal to the main control board. It is usually caused by the sensor's electrical resistance falling outside of its normal range due to internal component failure or a loose connection in the wiring harness. Because the boiler can no longer accurately monitor heat levels, 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?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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