[well folks problem solved!!! new pcb boards changed out all controls working c/h & water fine --thanks for your recomended option but this has been the cure not cheep but effective :D :) :)
SORRY THE BOILER IS ARISTON EURO COMBI A/27MFFI FITTED 2ND TEMPERATURE PROBE AS EVEN NEWONES CAN BE FAULTY BUT STILL BOILER RUNS WHEN MAINS SWITCHED ON & NO PROGROMMER CONNECTED--HOT WATER HEATS WHEN TAP TURNED ON BUT NO TEMP CONTROL [VERRY HOT] PROBE ACTIVATES MICRO ON HOT WATER WHEN...
BOILER RUNS CONSTANTLY c/H & WATER WITHOUT TIME CLOCK ON OR OFF ---REPLACED MAINFLOW THERMO CENSER BUT NO CHANGE ---BOILER RUNNING AS IF OVERRIDEN ALL CONTROL'S HELP!!! :(