uP High

Boiler Fault Code uP

Also written as UP — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code uP appears across 1 boiler brand and 5 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is currently stuck in its internal computer programming mode and hasn't been set up to operate as a heater yet. (As reported on Ideal Logic Combi ESP1)

Pick your boiler brand for the uP fix

Ideal uP 5 models

Source

Information for the uP 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