How much does it cost to fix boiler error code Ad?

Typical repair cost for the boiler Ad fault is £90-180 including labour.

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Boiler Fault Code Ad

Also written as AD — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code Ad 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 having trouble communicating with the sensor that monitors the temperature of your hot water cylinder. (As reported on Worcester Bosch WR325 RSF)

Pick your boiler brand for the Ad fix

Worcester Bosch Ad 13 models

Source

Information for the Ad 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