BoilerFaultCodes 87 H.....3..... High
Boiler Fault Code 87 H.....3.....
Also written as 87H3 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 87 H.....3..... 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 is struggling to accurately measure the temperature of the water used for your taps and shower, which will likely prevent you from getting hot water. (As reported on Ideal Isar M30 / M100)
Pick your boiler brand for the 87 H.....3..... fix
Source
Information for the 87 H.....3..... 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