High
12 on Ravenheat TS 90

Your boiler's internal thermometer for the central heating has stopped working correctly, meaning the system cannot safely monitor its own temperature.

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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