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

Typical repair cost for the boiler 51 fault is £0-120 including labour.

51 Medium

Boiler Fault Code 51

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 51 appears across 5 boiler brands and 39 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has lost its wireless connection with your thermostat or remote control, meaning they can no longer talk to each other to manage your heating. (As reported on Alpha E-Tec Regular)

Pick your boiler brand for the 51 fix

Alpha 51 23 models Ferroli 51 2 models Ideal 51 3 models Viessmann 51 8 models Vokera 51 3 models

Source

Information for the 51 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →

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