BoilerFaultCodesTechnical description
The sensor test has failed – cabling and plug sensors need checking
What causes this fault?
This fault happens when the boiler’s central brain performs a self-check and notices that the temperature sensors are not communicating correctly. It is usually caused by a loose connection in the internal wiring or a sensor that has reached the end of its life and is sending an impossible reading. Because the boiler cannot accurately track how hot the water is getting, it shuts down as a safety precaution.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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