Perplexing dishwasher problem

[clowes_ian]

Hi all

Our diswasher stopped filling, so I took a look at the valve on it.

When in the machine my DMM reads 230V (relative to the chassis of the d/washer) on both terminals when water is being called for. Hence no effective voltage across it and no water flows.

If I take it out and connect it to 230V then it works as expected: hums and lets water pass.

While it is out the disconnected terminals have 230V across them. As soon as I put the valve back in these revert to zero difference, and both at 230V.

Does this make sense to anyone?

IanC

[Andy Hall]

Yes.

I suspect that there is an open circuit on the neutral side of the supply to the valve which is why both sides show 230v relative to ground.

However, a DMM is very high impedance. When you connect across the valve terminals with the valve removed you have a capacitative coupling to neutral or ground or wires that are neutral or ground. Hence it reads 230v.

With the power off and disconnected, try tracing the neutral wire back to its terminal, the controller or other common point. Do this physically and then measure with the meter on the low resistance range.

I reckon that you will find an open circuit in the wire. It may be further back of course towards the main neutral of the appliance

The solution is to replace the wire of course.

One of the classic problem areas with dishwashers is that the wiring passes across the door hinge, flexes and breaks. You might want to check that there is no damage in that area to this or any other wires.