BoilerFaultCodes Po Low
Boiler Fault Code Po
Also written as PO — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Po 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 is simply running its pump for a short time after heating to distribute residual warmth, which is a normal part of the cooling-down process. (As reported on Biasi Advance Plus)
Pick your boiler brand for the Po fix
Source
Information for the Po 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