How much does it cost to fix Ferroli error code F41?

Typical repair cost for the Ferroli F41 fault is £100-£350 including labour.

F41 High

Ferroli F41 Fault Code

Q: What does the Ferroli F41 fault code mean?

Your boiler has sensed that the temperature is rising too quickly inside the unit, often caused by water not flowing through the pipes fast enough.

The Ferroli F41 fault code means: your boiler has sensed that the temperature is rising too quickly inside the unit, often caused by water not flowing through the pipes fast enough.. It appears on 10 Ferroli models in our database.

Technical description: Activation of maximum ELTA T protection

What causes the Ferroli F41 fault?

This fault occurs when the boiler's internal sensors detect that the heat is increasing much faster than the water can carry it away. The most common reason is a restriction in water flow, often caused by a failing pump or a build-up of sludge and debris blocking the narrow pipes inside the heat exchanger.

This issue often surfaces in autumn when the heating is turned back on after a long summer break, as pump components can seize or sludge can settle during periods of inactivity.

Typical repair cost £100-£350 (including labour)

DIY fix possible

Check that your boiler pressure is between 1.0 and 1.5 barEnsure all radiator valves and isolation valves are fully openCheck for any air trapped in the system and bleed your radiators

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Ferroli models that show the F41 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ferroli F41 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026