High
U 00 on Vokera Condexa Pro

Your boiler's main computer control panel is reporting a general failure, meaning it cannot communicate correctly to start the heating process.

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

errors from the Master board

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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