Boiler Fault Code DHW PUMP indicator Slow flash

Also written as DHWPUMPINDICATORSLOWFLASH — same fault.

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

Fault code DHW PUMP indicator Slow 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's electronic brain is experiencing a minor internal error and needs a service visit to replace a faulty control component. (As reported on Grant Vortex Eco)