High
Er99 on Biasi Activa

Your boiler has lost its configuration settings or isn't receiving power correctly, meaning it doesn't know which specific model it is supposed to be.

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

No power / Boiler type not correctly set in Pr01

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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