Low
LED4 (Permanent) on Ferroli Falcon

Your boiler is correctly operating in heating mode, and the light indicates that your central heating system is currently active.

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 Boiler Falcon Ii 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 room thermostat or boiler timer settingsTurn down the temperature dial on your thermostat to see if the light turns offIf you want the heating off, ensure your wall controller is set to off or standby

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All 22 fault codes on the Falcon

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

4 (Flashing)5 (Flashing)Boiler lock outBottom red lightHeating demand light OFFHeating demand light ONLED 3 OFF (DHW Mode)LED 4LED 4 Flashing (DHW Mode)LED 5 FlashingLED 5 ONLED1LED2LED3LED4 flashingLED5 (Permanent)Low water pressure light ONRed light (egg timer symbol)Red lockout lightTap symbol light OFFTap symbol light ON

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