High
E23 on Biasi Rinnova Adaptive Combi

Your boiler's internal computer brain is having trouble communicating or has lost power, meaning the system cannot safely operate your heating or hot water.

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

Control panel elect. p.c.b. / Main electronic p.c.b. / Fuses

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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Related fault codes

E01View →E24View →

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