Low
4 (Flashing Light) on Ferroli F24b

Your boiler is currently in standby mode and is simply waiting for a signal from your thermostat or hot water tap to start heating.

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

Central Heating standby

From this model's manual
Verified against the Bm Ferroli F24b Installation Servicing Instructions Manual 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 your thermostat or programmer is set to a temperature higher than the current room temperatureEnsure your heating timer is currently switched to the 'on' periodOpen a hot water tap to see if the boiler fires up for hot water demand

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