How much does it cost to fix boiler error code 315?

Typical repair cost for the boiler 315 fault is £150-300 including labour.

315 High

Boiler Fault Code 315

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 315 appears across 1 boiler brand 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 is struggling to detect the water flowing through its internal pipes, which is causing it to stop heating as a safety precaution. (As reported on Worcester Bosch Greenstar 12i System)

Pick your boiler brand for the 315 fix

Worcester Bosch 315 2 models

Source

Information for the 315 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