How much does it cost to fix boiler error code 504?

Typical repair cost for the boiler 504 fault is £90-280 including labour.

504 High

Boiler Fault Code 504

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code 504 appears across 1 boiler brand and 1 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 that the flame has gone out several times unexpectedly, which has caused it to stop working for safety. (As reported on Ariston Alteas One)

Pick your boiler brand for the 504 fix

Ariston 504 1 model

Source

Information for the 504 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