How much does it cost to fix boiler error code E73?

Typical repair cost for the boiler E73 fault is £150-300 including labour.

E73 High

Boiler Fault Code E73

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 7 July 2026

Fault code E73 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 is having a communication error because a small electronic key, which tells the system how to operate, is not being detected correctly. (As reported on Keston Qudos 28S)

Pick your boiler brand for the E73 fix

Keston E73 1 model

Source

Information for the E73 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