BoilerFaultCodes D4 271 High
Boiler Fault Code D4 271
Also written as D4271 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code D4 271 appears across 1 boiler brand and 11 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler has detected that the water inside the unit is getting too hot compared to the water travelling to your radiators, causing it to shut down to prevent damage. (As reported on Worcester Bosch Greenstar 12i System)
Pick your boiler brand for the D4 271 fix
Source
Information for the D4 271 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