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A short pulse every 4 seconds on Biasi Garda M90f

Your boiler is currently switched off but is monitoring the temperature 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 (function control in O position). Anti-freeze system active.

From this model's manual
Verified against the Biasi Garda M90f installation & service manual, page 19.
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

Turn the main control knob from the 'O' (Off) position to either 'Summer' or 'Winter' mode to restore normal heating and hot water.

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