hi u can dowloand the 24cdi worcester installation manual online it will explain the light faults. had a quick look it says if hot water and ch lights flashing slowly then its classed as fault point G. it says check water pressure is ok , then reset the boiler. if it does not solve the problem check ch stat , over heat stat if all fails pcb fault. http://www.centralheating.co.uk/Boiler-Manuals/worcester-bosch-boiler-manuals/worcester-bosch-discontinued-boiler-manuals
kash
December 2012