How much does it cost to fix Ferroli error code B-3?

Typical repair cost for the Ferroli B-3 fault is £80-150 including labour.

B-3 High

Ferroli B-3 Fault Code

Q: What does the Ferroli B-3 fault code mean?

Your boiler is currently switched on but is not receiving a signal from your thermostat or timer to tell it to start heating your home.

Also written as B3 — same fault.

The Ferroli B-3 fault code means: your boiler is currently switched on but is not receiving a signal from your thermostat or timer to tell it to start heating your home.. It appears on 2 Ferroli models in our database.

Technical description: Roomstat (72) or clock (62) not calling for heat

Typical repair cost £80-150 (including labour)

DIY fix possible

Check your room thermostat is set to a temperature higher than the current room temperature.Ensure your heating programmer or clock is set to 'On' and the current time is correctly displayed.Replace the batteries in your wireless thermostat if applicable, then wait a few minutes for a signal to establish.

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Ferroli models that show the B-3 fault code

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

Source

Ferroli B-3 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