High
Lights: On, Flash, On on Baxi Solo 2

Your boiler has detected a temperature sensor fault, meaning it can no longer accurately monitor how hot the water is getting.

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

Go to Thermistor section of the fault finding instructions. (Resistance should be between 0.5kΩ & 20kΩ)

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.

Find a Gas Safe engineer
Search the official register →

Related fault codes

Lights: On, On, FlashView →Lights: On, Flash, FlashView →

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