How much does it cost to fix boiler error code Air Proving LOCKOUT?

Typical repair cost for the boiler Air Proving LOCKOUT fault is £120-280 including labour.

Air Proving LOCKOUT High

Boiler Fault Code Air Proving LOCKOUT

Also written as AIRPROVINGLOCKOUT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Air Proving LOCKOUT 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 has stopped working because it cannot confirm that harmful exhaust gases are being safely cleared through the flue pipe. (As reported on Potterton Performa SL HE 9 2)

Pick your boiler brand for the Air Proving LOCKOUT fix

Potterton Air Proving LOCKOUT 2 models

Source

Information for the Air Proving LOCKOUT 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