smeg wm63141bk

smeg wm63141bk no fill can hear inlet valve humming no water entering the machine, checked water supply which is ok. tested resistance on inlet valves which are ok, on normal set up i would diagnose faulty water valve , question is on water inlet pipe from main water tap there is some form of valve? seen similar to this on some bosch machines heard it described as an aquastop,could this be the problem as it is a sealed unit, i am not sure whats inside no wiring to it either. never looked at one of these before so help appreciated, if you have any ideas could you please give some part numbers aswell, thanks Darren.