High
E85 on Biasi Rinnova Adaptive Combi

Your boiler's main control board has detected an electrical fault or an unstable power supply, preventing the unit from operating 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

E04View →

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