High
E.01 – .02 on Baxi Suprima 40

Your boiler is confused because the water returning to it seems hotter than the water it just sent out, suggesting a circulation error or a sensor fault.

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

Temperature measured by return sensor greater than flow sensor.

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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