High
E.01 – .02 on Baxi Suprima 115

Your boiler is confused because the pipe leading back to the unit is showing a higher temperature than the pipe sending heat out, which usually means water is flowing the wrong way or a sensor is faulty.

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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