High
E.02 – .17 on Baxi Suprima 50

Your boiler's internal computer has lost contact with the gas control unit, meaning the system cannot safely manage the fuel it needs to stay alight.

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

Loss of communication between gas valve and boiler printed circuit board (PCB) or fault in air/gas unit.

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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