High
E.04 – .02 on Baxi Suprima 115

Your boiler has lost its connection to the sensor that monitors internal water temperature, meaning it cannot safely heat your home until the part is checked or replaced.

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

Permanent fault. Flow temperature sensor open-circuited, sensor not or badly connected, bad connection or sensor fault.

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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