Hd High

Boiler Fault Code Hd

Also written as HD — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code Hd 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 main heat pump unit is unable to talk to the secondary unit, meaning the system cannot coordinate properly to heat your home. (As reported on Ideal HP290)

Pick your boiler brand for the Hd fix

Ideal Hd 1 model

Source

Information for the Hd 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