Low
4 (Permanent Light) on Ferroli F24b

Your boiler is currently detecting that your heating system is active and running normally.

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 circuit ON

From this model's manual
Verified against the Ferroli/Ferroli F24b 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 settings to see if the heating is set to 'on'Lower the room thermostat temperature to see if the code clearsIf you do not want the heating on, turn the heating controller or thermostat off

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All 9 fault codes on the F24b

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

4 (Flashing Light)5 (Flashing Light)5 (Permanent Light)4343 mmBoiler lock outLED 5 (Flashing light)Low water pressure

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