How much does it cost to fix boiler error code E595?

Typical repair cost for the boiler E595 fault is £150-250 including labour.

E595 High

Boiler Fault Code E595

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code E595 appears across 1 boiler brand and 6 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler's electronic control board is having trouble talking to the display panel, meaning it cannot currently receive commands or show status updates. (As reported on Navien NCB 28 HE)

Pick your boiler brand for the E595 fix

Navien E595 6 models

Source

Information for the E595 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