Low
Normally operating boiler on Biasi Riva Compact 24S (M90E.24S)

Your boiler is currently working as it should and is simply communicating that it is in normal operating mode for the season you have selected.

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

1 second ON 1 second OFF (function control in Winter or Summer position)

From this model's manual
Verified against the Biasi Riva Compact 24s installation & service manual.
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 light sequence indicates normal operation.Ensure your thermostat is set to the desired temperature.Ensure your timer or programmer is set to 'ON'.

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