BoilerFaultCodesYour boiler has detected a problem with one of its internal temperature sensors and has stopped working as a safety 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.
What causes this fault?
This fault occurs when the internal temperature sensors, which monitor how hot the water is getting, fail to send a reliable signal to the boiler's brain. The most common reason is that the sensor has physically degraded or developed a chemical build-up over time, causing it to provide inaccurate readings. In some cases, the electrical wiring connecting these sensors has become loose or damaged, leading the boiler to shut down to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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