High
E.01 – .12 on Baxi Assure

Your boiler has sensed that the water returning from your radiators is hotter than the water leaving the boiler, which usually means there is a temporary circulation issue or a sensor mix-up.

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

Requires reset – temperature measured by return sensor greater than flow temperature.

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 →E15View →E40View →

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