How much does it cost to fix Biasi error code All operation lights OFF?

Typical repair cost for the Biasi All operation lights OFF fault is £100-350 including labour.

All operation lights OFF High

Biasi All operation lights OFF Fault Code

Q: What does the Biasi All operation lights OFF fault code mean?

Your boiler appears to have no power and is completely unresponsive when you try to use your heating or hot water.

Also written as ALLOPERATIONLIGHTSOFF — same fault.

The Biasi All operation lights OFF fault code means: your boiler appears to have no power and is completely unresponsive when you try to use your heating or hot water.. It appears on 2 Biasi models in our database.

Technical description: The boiler doesn't start in either c.h. or d.h.w. mode. Fan still.

Typical repair cost £100-350 (including labour)

DIY fix possible

Check if the boiler's fused spur switch is turned onCheck your home's main consumer unit (fuse box) for a tripped circuit breakerReplace the 3-amp fuse in the boiler's external electrical spur

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Biasi models that show the All operation lights OFF fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Biasi All operation lights OFF fault code information on this page is sourced and cross-checked against the official Biasi service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026