782 High

Boiler Fault Code 782

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code 782 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 has lost communication with the internal 3-way valve, meaning it cannot correctly switch between heating your radiators and providing hot water. (As reported on Navien NCB CE)

Pick your boiler brand for the 782 fix

Source

Information for the 782 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