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A short pulse every 4 seconds on Biasi Riva Compact 24S (M90E.24S)

Your boiler is currently on standby and is performing its normal automatic safety check to prevent the internal pipes from freezing.

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 in stand-by condition. Anti-freeze system active.

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 normal operation.Ensure the gas and electricity supply to the boiler remain switched on during cold weather.If you require heating or hot water, ensure your external controls or thermostat are turned up.

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