P.05 Low

Boiler Fault Code P.05

Also written as P05 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code P.05 appears across 3 boiler brands and 18 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 performing an automatic air-removal process after detecting a change in water pressure, and it will return to normal operation once this cycle finishes. (As reported on Glow-worm Sustain 12s)

Pick your boiler brand for the P.05 fix

Glow-worm P.05 10 models Heatline P.05 6 models Vaillant P.05 2 models

Source

Information for the P.05 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