Low
LED3 on Ferroli Combi 77 FF Popular

Your boiler is currently reading a request to provide hot water or heating, which is a normal operational signal and not a fault unless the boiler fails to fire up.

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

Demand for heat from D.H.W. or C.H. (Connection 68 on P.C.B. switched on)

From this model's manual
Verified against the Ferroli/Ferroli Combi 77 Ff Popular 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 that your room thermostat is turned up to trigger a heating demandEnsure your programmer or timer is set to an 'On' periodOpen a hot water tap fully to see if the boiler responds to the demand

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Related fault codes

LED1View →LED2View →

All 9 fault codes on the Combi 77 FF Popular

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

5 red38/33A210LED 2 on P.C.B. alightLED1LED1 onLED2Relay 2 energised after 2 sec

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