High
E.02 – .17 on Baxi 800

Your boiler's main control centre is unable to talk to the part that manages the gas supply, meaning the system cannot safely light itself.

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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