Low
1 second ON 1 second OFF on Biasi Riva Compact HE M96a

Your boiler is currently operating normally and is simply indicating that it is actively heating your radiators or hot water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

Boiler ON condition (function control in C.H. or D.H.W. position).

From this model's manual
Verified against the Biasi Riva Compact 24s installation & service manual, page 23.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check your thermostat to see if it is calling for heatTurn on a hot tap to confirm the boiler respondsNo action is required as this is a status indicator, not a fault

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