Low
LED4 flashing on Ferroli Falcon

Your boiler is currently in standby mode and is working exactly as it should, waiting for a signal to provide heat or hot water.

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 stand-by

From this model's manual
Verified against the Ferroli/Ferroli Falcon 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 is set to a higher temperature than the current room temperatureEnsure your heating timer or programmer is currently in an 'on' periodVerify that the boiler's own selector switch is set to the heating or hot water mode

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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 (Permanent)LED5 (Permanent)Low water pressure light ONRed light (egg timer symbol)Red lockout lightTap symbol light OFFTap symbol light ON

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