High
89 on Biasi Antares Combi

Your boiler's internal computer has encountered a technical glitch or an issue with the electrical power coming into your home.

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.

What the manual says

Manufacturer manual

Internal error (usually hardware) or problems with the mains electrical supply (excessive distortion of waveform).

From this model's manual
Verified against the Biasi Antares Combi installation & service manual, page 13.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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