My potterton suprima 60L has recently started misbehaving,it is taking no notice of the controller (Mini Minder e ) which has been tested and is good,the boiler can only be controlled by switching on and off at the mains,the only problem i've found is the motorised valve to the central heating is broken inside, is this the problem or should i be looking at the PCB,the boiler itself is firing up as normal without having to reset but as i have already said only by switching the mains on and off,would gratefully accept some good advice.