BoilerFaultCodes P.3 Low
Boiler Fault Code P.3
Also written as P3 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code P.3 appears across 1 boiler brand and 13 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is undergoing a temporary calibration process where it checks its heating settings; it is not a fault, but a normal status message. (As reported on Vaillant ecoTEC plus)
Pick your boiler brand for the P.3 fix
Source
Information for the P.3 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