High
E.01 – .12 on Baxi Suprima 100

Your boiler has stopped running because it thinks the water returning to the unit is hotter than the water leaving it, which usually indicates a circulation problem.

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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