Low
Frost protect operation on Biasi Riva Compact 24S (M90E.24S)

Your boiler has sensed very cold temperatures and is running its internal pump or burner to prevent its 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

Lamp 3 ON

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

Check that your electricity and gas supplies are turned on so the boiler can finish its cycle.Ensure any visible condensate pipes leading outside are not frozen or blocked.Wait for the boiler to finish the cycle; the light should turn off once the water reaches a safe temperature.

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