Low
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.

Shared across the Garda M90f. range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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

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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All 5 fault codes on the Garda M90f

Seeing a different code? Every code this model can display, in one place.

1 second ON 1 second OFF1012lock-out light

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