Low
1 second ON / 1 second OFF on Biasi Riva Compact 24S (M90E.24S)

Your boiler is operating normally and is currently responding to a demand for heating 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

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

No action is required as this is a status indicator rather than a fault.Ensure your thermostat or timer is set to your preferred schedule.If the boiler is running but radiators are cold, check that radiator valves are open.

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