Boiler Fault Code CH PUMP Fast flash

Also written as CHPUMPFASTFLASH — same fault.

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

Fault code CH PUMP 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's temperature sensor is disconnected or faulty, meaning it cannot accurately track the heat of the water and has stopped your heating from working. (As reported on Grant Vortex Eco)