Boiler Fault Code DHW PUMP indicator Fast flash

Also written as DHWPUMPINDICATORFASTFLASH — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code DHW PUMP indicator Fast flash appears across 1 boiler brand and 5 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 inside its internal storage tank, which means it may fail to provide hot water correctly. (As reported on Grant Vortex Eco)