How much does it cost to fix boiler error code Internal fault?

Typical repair cost for the boiler Internal fault fault is £120-250 including labour.

Internal fault High

Boiler Fault Code Internal fault

Also written as INTERNALFAULT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code Internal fault appears across 2 boiler brands and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has detected an internal software or processing error that prevents it from starting until it is properly restarted. (As reported on Vokera Option)

Pick your boiler brand for the Internal fault fix

Vokera Internal fault 1 model Worcester Bosch Internal fault 1 model

Source

Information for the Internal fault 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 7 July 2026