High
12 on Ravenheat 120

Your boiler's internal thermometer that monitors water temperature for your heating has stopped working correctly, causing the system to shut down.

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

Failed heating sensor – issue with heating sensor and could need replacing

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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