How much does it cost to fix boiler error code 5 02?

Typical repair cost for the boiler 5 02 fault is £150-300 including labour.

5 02 Emergency

Boiler Fault Code 5 02

Also written as 502 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code 5 02 appears across 2 boiler brands and 15 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 a flame signal when it is not supposed to be running, which indicates a potential safety issue with the internal electronics or gas controls. (As reported on Ariston E-Combi One 30)

Pick your boiler brand for the 5 02 fix

Ariston 5 02 14 models Chaffoteaux 5 02 1 model

Source

Information for the 5 02 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