High
E78 on Biasi Rinnova Adaptive Combi

Your boiler has detected an internal electrical supply problem or a failure within its main control board, meaning it cannot operate safely.

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

Main electronic p.c.b. / Power supply line

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 →E11View →

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