How much does it cost to fix Ferroli error code 51?

Typical repair cost for the Ferroli 51 fault is £90-180 including labour.

51 Medium

Ferroli 51 Fault Code

Q: What does the Ferroli 51 fault code mean?

Your boiler has sensed that the temperature inside the unit is too low and has triggered a safety mode to prevent the pipes from freezing.

The Ferroli 51 fault code means: your boiler has sensed that the temperature inside the unit is too low and has triggered a safety mode to prevent the pipes from freezing.. It appears on 2 Ferroli models in our database.

Technical description: Central heating frost thermostat

Typical repair cost £90-180 (including labour)

DIY fix possible

Ensure the central heating system is switched on at the programmer.Carefully increase the room thermostat setting to encourage the boiler to fire up.If the boiler is in a very cold location like a garage, safely use a heater nearby to raise the ambient temperature around the unit.

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Ferroli models that show the 51 fault code

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

Source

Ferroli 51 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