High
E.04 – .01 on Baxi Assure

Your boiler has lost track of the water temperature because a internal sensor cable has broken or failed, preventing the system from heating up safely.

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

Flow temperature sensor short-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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Related fault codes

E110View →

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