High
1076 W on Worcester Bosch Junior 24i

Your boiler has lost its connection to the sensor that monitors internal heat levels, meaning it has shut down as a safety precaution.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

No signal from the temperature sensor at the heating block available – replace the temperature sensor, the connecting lead or the control unit

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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