How much does it cost to fix boiler error code P 0.4?

Typical repair cost for the boiler P 0.4 fault is £0-120 including labour.

P 0.4 High

Boiler Fault Code P 0.4

Also written as P04 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code P 0.4 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler has stopped working because the water pressure inside the system has dropped too low to operate safely. (As reported on Potterton Powermax HE)

Pick your boiler brand for the P 0.4 fix

Potterton P 0.4 1 model

Source

Information for the P 0.4 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