High
E12 on Biasi Inovia 2020

Your boiler has detected that a sensor responsible for monitoring the temperature of the water returning from your radiators has developed a fault, preventing the system from operating correctly.

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

Faulty central heating temp. probe NTC (return)

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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Related fault codes

E05View →E06View →E11View →

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